Do Carbs Kill Your Brain?


Recently, I’ve been hearing from many patients who have read Dr. Perlmutter’s new book, Grain Brain, and are now concerned about their carb intake. In his book, Dr. Perlmutter suggests that dietary carbohydrates cause high blood sugar, inflammation, and other effects that lead to a “toxic brain,” which can then develop into neurological conditions such as Alzheimer’s, Parkinson’s, depression, and others. Based on this line of causality, he recommends that everyone consume a very low carb diet (<60g per day) in order to prevent neurological disease.

First of all, I’d like to point out that very low carb (VLC) and ketogenic diets can be effective therapeutic tools for treating many neurological disorders. I touched on this briefly a while back in my podcast with Emily Deans, and initial studies on low-carb diets and mental health have shown promise. (1, 2, 3, 4) Because Dr. Perlmutter is a neurologist, it makes sense that he would be a proponent of low-carb diets for his patients based on these therapeutic effects.

Does eating carbs destroy your brain and lead to neurological disease?

However, recommending a low-carb diet as an intervention for sick people is very different from promoting it as a preventative measure for the entire population, which is what Dr. Perlmutter does in Grain Brain. His approach would be somewhat akin to recommending that everyone go on the Autoimmune Protocol to prevent autoimmune disease, which would be unnecessarily restrictive and unhelpful. It’s important to realize that just because a low-carb diet can help treat neurological disorders, doesn’t mean the carbs caused the disorder in the first place. While I don’t argue with the idea that refined and processed carbs like flour and sugar contribute to modern disease, there’s no evidence to suggest that unrefined, whole-food carbohydrates do. In fact, there are three compelling reasons why this is not the case.

#1 – We evolved eating whole-food carbohydrates

The first reason it doesn’t make sense that carbohydrates cause neurological disorders is that we’ve been eating carbs for a very long time, and we’re well adapted to digesting and metabolizing them. For instance, fruit has been part of the human diet for longer than we’ve been recognizably human, and while starch hasn’t been part of the human diet for quite as long, it’s clear that we’ve evolved mechanisms to digest and utilize it efficiently.

Compared with most primates, humans have many more copies of the gene AMY1, which is essential for breaking down starches. (5) This gene is unusual in that the number of copies varies greatly between populations, with more copies present in populations that consume more starch. This indicates that starch played a significant role in our evolution, and some scientists have even argued that consumption of starch was partially responsible for the increase in our brain size.

In addition to possessing the ability to break down complex carbohydrates, our bodies require glucose to function properly and maintain homeostasis. The fact that humans can produce glucose from protein is often used as an argument that we don’t need to eat glucose, but rather than viewing this as evidence that that glucose isn’t important, we might view it as evidence that glucose is so metabolically essential that we evolved a mechanism to produce it even when it’s absent from the diet.

#2 - There are many traditional cultures with high carb intake and low or nonexistent rates of neurological disease

If carbohydrates cause neurological disorders, one would expect to see high rates of dementia and similar diseases in populations where carbs constitute a significant portion of the diet. But as it turns out, many of the cultures that maintain the lowest rates of neurological and other inflammatory disease rely heavily on carbohydrate-dense dietary staples. For example, the Hadza of north-central Tanzania and the Kuna of Panama obtain a high percentage of their total calories from foods that are high in natural sugars, such as fruit, starchy tubers and honey, yet they are remarkably lean, fit and free of modern disease. (6, 7)

Other examples include the Kitava in the Pacific Islands, Tukisenta in the Papa New Guinea Highlands, and the Okinawans in Japan. The Kitavan diet is 69% carb, with a high reliance on starchy tubers such as yams, and sugary tropical fruits such as banana and papaya. (8) The Okinawan diet is even more carb-heavy at 85% carbohydrate, mostly from sweet potato. (9) Finally, the Tukisenta diet is astonishingly high in carbohydrate at over 90%. (10) All of these cultures are fit and lean with practically non-existent rates of neurological disorders and other modern chronic disease. (11)

#3 - Modern research does not support the notion that ‘safe’ carbs are harmful

The claim that carbohydrates from whole-food sources cause neurological disorders is not supported by anthropological evidence. In addition, modern studies on the health effects of carb-dense foods such as fruit also fail to support Perlmutter’s hypothesis. In fact, studies overall suggest that eating whole, fresh fruit may actually decrease the risk of health issues such as obesity and diabetes, and that limiting fruit intake has no effect on blood sugar, weight loss or waist circumference. (12, 13)

As you may know if you’ve been following my website, there is plenty of modern research demonstrating that diets rich in refined and processed carbohydrates are harmful. However, this is not due to carb content alone, and there’s no evidence that whole-food carbs have the same effect. When an author or expert recommends excluding or severely limiting one of three macronutrients that humans consume, the evidence demonstrating harm should be strong—not only because of the inconvenience of following such a restricted diet, but because extreme diets (ketogenic or VLC diets in this case) are not always harmless. In my practice I’ve seen many patients who’ve worsened on long-term VLC diets, including those with adrenal issues and poor thyroid function. Long-term VLC diets can also lead to imbalances in gut bacteria due to a lack of prebiotic fiber, which can result in digestive issues.

As I’ve always maintained, you need to find out what works for you and tailor your diet to your specific health goals, rather than follow a canned approach. This is exactly what I’ll teach you to do in my book, Your Personal Paleo Code, which is coming out at the end of December.

Have you read Grain Brain? What do you think about very low carb diets? Share your thoughts in the comments!

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  1. Tyler Wood says

    I have not read this book but I’ve heard and seen the buzz the last month or so.

    This reminds of the “debate” you participated in at AHS 2012 in Boston. I think your responses very much much the same to this. One of the things I’ve re-learned over the last few years, as with everything, there are two sides to everything in the nutrition debate. And both are compelling. Given that Perlmutter is in trenches with this kind of work, I’d be interested in his take on your post.

    In the end, as you said, “you need to find out what works for you and tailor your diet to your specific health goals, rather than follow a canned approach” is the best advise I’ve heard. One size doesn’t fit all.


      • Mr. Keto says

        I don’t think finding “What works for me” works for diseases like Alzheimer’s since it may take
        a long time to develop and I can’t really tell if I’m damaging my brain on a daily basis by eating
        my whole grains. I look to experts to guide me as far as what I should I and right now
        I’m only hearing contradictions when it comes to whole grains. (Most experts agree on
        highly refined carbs)

        • says

          Mr. Keto, you will continue to see contradictions in research results and in recommendations due to the way we currently examine food. We perform micro-analyses of food, often out of context of real diets, extrapolating the results into a meal plan that has never been practiced on this planet before (meaning it is an experiment). Without grounding the results of dietary research, we get all kinds of crazy results (e.g., don’t eat any fat, red meat is bad for you, animal foods cause cancer–all of these statements are supported by research, though I would not consider it good research). For me, I view all dietary recommendations through the lens of long time use and exposure to people (meaning I often look to indigenous and traditional cultures to see what they consumed, how they processed the foods, what they combined foods with, etc., etc.). What I like about Chris Kresser’s approach is that he combines anthropological data with modern research (which I feel creates the most solid total argument). These groups (indigenous and traditional cultures) often had aspects of health we do not currently possess (which I will not get into now). As far as grains, they are very much maligned in most paleo circles. However, we can see that some cultures relied on grains as a staple and enjoyed excellent health (contradicting the statement that all grains should be avoided). So for me, the real question isn’t if we should or should not eat grains, the real question is what grains we should choose to eat and what dietary components combined with them to build an effective diet that maintained health and produced healthy, well formed children. I hope this can be of help. Best wishes to you.

          • BrittDoc says

            Arthur Haines, that is BRILLIANT! Exactly the way I look at nutritional research, but without the eloquence you used. People need to realize that foods like whole grains have been a staple of so many diets for hundreds and hundreds of years, and blaming them fir a new or growing health phenomenon is utterly ridiculous. Not only that, but how does saying these types of foods are “deadly” (“wheat is murder”? Give me a break) square with the fact that other countries CURRENTLY eat diets rich in the same food and the occurrence of the same disease in question is so low it’s almost non existent. Some may claim it’s because of the way we process our grains (using the same example), but that’s not a valid argument- we import and export food to the point where almost no one is eating food solely from their country of residence. The hysteria-based trend diet -Atkins rings a bell and gluten-free is in the same boat in my eyes- is running rampant these days, and quite frankly, I don’t see myself ever buying into any of the hype. No one can ever tell me that a whole food that has been consumed for thousands of years is all of a sudden a toxic substance. It’s nonsense in large part, and if more people researched these alarmist trends, they would find that there is either NO research backing them up or research that isn’t properly conducted, or like Arthur said, completely taken out of context.

            • Jessie says

              The point your all missing is the fact that we have NOT been eating like this for thousands of years. We are NOT eating the same grains that our ancestors ate thousands of years ago. The grains we eat today and have been eating for a long time now are all Genetically
              Modified and they have been over and over again to the point that our bodies can not accept them. Our bodies don’t know what to do with these GMO foods so they get stored here and there in our bodies and start to become deceased. All the animals are being forced to eat these GMO grains and we in turn eat the animals and we take them in again. These GMO foods are all around us and we keep consuming them in almost everything we eat. That is why deceases like diabetes, depression, dementia, Alzheimer’s and other deceases have escalated to frightening and alarming proportions. If I’m going to occasionally eat beef its going to be grass fed. If I’m going to have any carbs it’ll be from heirloom seeds that have been organically grown. If I’m going to have an egg , a glass of milk or a piece of cheese its NOT going to come from an animal that was stuffed with GMO grains and feeds that I know will eventually kill me. I’m 100% behind Dr.Perlmutter and have been
              practising his beliefs long before his book came out.

                • Rutus says

                  It’s not about living forever. It’s about living healthy and staying OUT of the nursing home. Being able go make decisions for oneself, not becoming a burden to society.

              • Aerin says

                Do you even know what is in GM food? Didn’t think so. BTW, no GM wheat is grown or sold anywhere in the world.

              • Andrew says

                Wow. That is simply not the way food works. You clearly have no idea what GMO means, or how each crop is modified. I encourage you to research how the digestive system actually works instead of taking your eating advice from a hyperbolic link bait blog somewhere. Making something resistant to disease does not store anything anywhere in your body the normal food wouldn’t. In fact, if they had a genetic therapy vaccine treatment for Alzheimer’s, people would line up around the world for it without a second thought. Its much more complicated than boiling it down to “GMO=BAD”.

              • Danielle says

                I agree. I haven’t finished the book but what I’ve taken out of it so far is not that carbs are the enemy but the grains that have been processed beyond recognition throughout the years is the problem. He’s not promoting low carb as much as low grain because there is no longer any such thing as ‘whole’ grain unless you shop in the middle east.

              • Paul says

                GMO foods have been extensively studied by all leading health national health organizations and there is no evidence that they are unhealthful.
                The idea that “heirloom seeds” — which themselves are the product of generations of human hybridization — somehow produce healthier food is not supported in fact. There is just no reason to believe that using precise genetic techniques to alter plants is somehow more dangerous than using more primitive techniques to achieve the same end.
                The anti-GMO hysteria is based on a non-scientific belief that some things deemed “natural” are inherently better than those things deemed “unnatural”.

            • Melissa says

              Here is the issue, people for thousands of years had the correct gut bacteria to properly digest those grains they were consuming. Other cultures around the world also still enjoy gut health. Modern day antibiotics, toxins, and stress can take a tole on our gut health and many people, myself included cannot properly digest grains in any form and this contributes to a bloated belly, digestive issues, joint pain and many other woes if I even consume white rice or gluten free oats. My husband on the other hand has no issue with them, and he also never had the months of antibiotics I was force fed on as a baby due to ear infections (milk allergy, I now know) We need to find out what our bodies need and follow suit. Just because a certain culture does great on grains does not mean modern day America can in the majority.

              • Art K says

                Melissa! I am exactly like you! I am now almost 60. I can’t eat any grains. I have a terrible time with all starches. Oats are bad! All rices are a nightmare. I break out in deadly skin rashes full of puss and oozing blood and syrupy fluid. This started in 1983 when I jumped in to the Macrobiotic Diet (Die! t) get it?) I thought the concept of 60% grains with a little vegees and seaweed was simple. After 2 weeks, I started breaking out in rashes all over my body. I will spare all of you the detail of the pain and misery. This went on for many years. Doctors told me it was a skin topical problem, so they sold me cremes and other junk. I finally got mad enough and went to Brookline, Mass. to find Dr. Michio Kushi, the founder and author of all the books I owned. When I arrived, I learned he said that smoking of tobacco was acceptable as long as it was clean. I smoked lots of cigars and they were “natural and expensive.” He said the rashes were a sign of detoxification and that I should hang in there. My youth was filled with Doctors. Ear infections, epilepsy, strep throat constantly, I drank milk as a youth too! Hernia at age 9. Fast forward. I really appreciate Dr. McDougall. He is the only one that seems to communicate and demonstrates the fact he cares. He is disturbed over the fact I cannot eat any starches he recommends. I can eat organic beans and other canned beans I get from Trader Joe’s. EVERY TIME I get soft and try again to eat a small amount of grains, sweet potato or white-organic or not, I break out on my hands, arms and legs and feet. My wife NEVER has a reaction like me. All bread is out by the way. I keep no meat in the house. No dairy. No eggs. No booze or beer or wine. No pot. No drugs by the pharma at all. I have retried fish, chicken and meat with no rash side effects. I simply had slower digestion because that is what meat does to us. I used to eat meat at least 3 times a day and was 100% stronger and more virile than I am now. Poor wife. I do not want colon, prostate, testicular, throat, brain and all the other locations to be hit with cancer. Duh! Now what do I do?

            • Mona brooks says

              Guess you have never heard of GMO wheat, which if grown in this country has 10,000 times more gluten than wheat grown in other parts of the world, especially Europe. Yes, wheat from even a hundred years ago was very different from what we are eating today. We have so altered the grains that our bodies’ cells would struggle to utilize them as food.
              More than my love for grains, i so love feeling well and being healthy. We have found great ways to eat well without grains!

          • Kathleen says

            Britt Doc and Mr. Haines: I’m about 2/3 through Perlmutter’s book and I really appreciate his references to current research. I notice you don’t include any links to back up your assertions so for me right now it’s Perlmutter one / you guys zero.

            • Aerin says

              Well, most of his “assertions” are common knowledge among people who know anything about nutrition. And citations are only as good as the science behind them.

        • Jako Manning says

          They also all agree that you should buy their latest book.

          I am concerned about the armful of meds my wife just bought from Amazon as listed in Grain Brain. I see her buying and taking the OTC meds…thats’ the easy part….but how well do they work when she sits down to a bowl of tortilla chips afterwards?

        • Richard says

          Mr. Kayo, it is not clear to me which contradictions or experts you are addressing in your comment. What is clear is that many cultures have been healthy, both mentally and physically, by consuming primarily whole grains for many years. Those cultures provide better evidence for me than labs and till science can prove the allegations against grains I will continue to consume whole grains.

          • beakernz says

            Have a look at the latest research on “Barleymax” a new type of barley preparation. All bowel and stool health markers greaty improved when subjects ate foods containing barleymax. Many of those markers indicate greater reduction of bowel/colon cancers as well. Sounds terrrrrible right?

            • Richard says

              Might be good stuff, need some research on it but one problem with it is the omega-6 to 3 is 25:1 which is way too high.

      • andrea mory says

        Really? You don’t actually fathom a time when “we’ were not yet recognizably human? Actually “we” as we know us, did not exist at the time he references. We did evolve though. So … do you also believe “we” have nothing to do with the melting of polar ice caps?

        • Dusty Diamond says

          “So … do you also believe “we” have nothing to do with the melting of polar ice caps?” Why don’t you ask the researchers who were trapped in the Antarctic ice a few weeks ago…

        • Chris says

          Speaking of hysteria…the reason for polar ice melt has no place in this conversation beyond a recognition that the fear mongering surrounding it is quite similar in pattern and nature to that which undergirds narrow minded theses like Dr. Perlmutter’s. This (and perhaps this has always been) is an age of irritatingly frequent, near sighted dogmatic theories swallowed whole by a public which prefers pat answers to everything. But fundamental scientific and even moral issues seldom have a perfect story arc laid out such that they satisfy our desire for good guys and bad guys. The age of Facebook knowledge prevails and Americans slowly entrench thelmselves, less willing to view life through a unifying set of lenses.

          • Megan Oien says

            Chris, 100% agree. Schools have successfully eradicated reason. People are only left with looking to the experts’ opinions. Most experts become experts by towing the line within the current paradigm. They speak out and they are discredited. And that is how we have remained sick and unhealthy in this country, by following those experts. And the cult of expertism rules all. Luckily, with the emergence of the internet, if you are willing to research and reason, the information is out there.
            And while I don’t agree with him on everything, I don’t think Kresser falls into the cult of experts group. I am speaking of those who come up through the conventional channels and the highly respected schools.

            • Chris says

              Academia is just as full of opinions as I am, but having a Dr in front of ones names lends credibility. And, hey, an education certainly is a valuable filter. However, the shifting currents of popular beliefs in intellectual circles is pretty sketchy. Once you have tailored analysis to fit your desired outcome, the game is over. As you say, the internet is a great aggregator or information, if only one has the logical tools and wisdom to wade through the tripe. If only I possessed the wisdom.

              • Chris says

                A few spelling issues with that one. And half thoughts. Sorry folks. I guess what I’m trying to get at is that intellectuals are very good at jumping on a popular bandwagon, often based on theory which is conflated with the outcome the academic desires to find.

          • Angela says

            Chris, no matter what I write I will never sound as smart or articulate as you, so I will just reply, “Yep.”

        • Rev. Ronald Roland says

          Sorry Andrea, there is no such thing as “evolution.” We were created human, even though we now hate our Creator. “Evolution” has been scientifically proven to be unfactual, from the Second Law of Thermodynamics (entropy), to irreducible complexity. Even the famous geological column supports Creation, not “evolution.” Until God created there was nothing to “evolve.” In fact, the idea of “evolution” was on such such shaky ground in the late 1800′s that Sir Julian Huxley had to declare it a scientific law – despite the facts. So much for scientific method! Perhaps we would know a little more about humanity and the universe if we approached it from the point of fact rather than fiction.

          • Peter says

            Now we’re really off topic. Rev. Ronald, there are no facts and no science for creation. As an evangelical Christian, I fully accept the overwhelming evidence of evolution and ascribe it, by faith, to God’s handiwork. I suggest that the only thing on shaky ground here is the notion that the Bible has anything to say about the science of modern nutrition. Please, sir, as a fellow human and a brother in Christ, may I recommend you subscribe to web blogs such as — science and faith in harmony. Peace.

            • Chris Page says

              I completely agree that this has nothing to do with the article. So if you are irritated at this discussion being here then just don’t read it.

              “There are no facts and no science for creation.” Actually there are no facts and science for macro evolution either (nobody in their right mind would disagree with micro evolution which is observable). Scientific laws apply to events and phenomena that can be reproduced and verified. Macro evolution can not be observed, and cannot be verified scientifically. All we have is the similarities in DNA that can be analyzed. This however does not sceintifically prove evolution. If there is a God, He could have (and to me it makes sense that he would have) used the same framework for life (DNA) and then modified it to create different species. When it comes to the issue of creation or randomness, all we can do (since we weren’t there and we can’t reproduce it) is look at the evidence and make a decision. I don’t agree with your statement as if it takes blind faith to believe in creation. Almost all of science leads me to the conclusion that it is far too complex to have been random. For example, if you took the number of characters in the most basic DNA (the supposed first cell), it would roughly equal the same number of letters in 5,000 encyclopedia books. Simple probability shows that the time for this to randomly arrage would by far exceed the age of the universe. So rather than reach the very rational conclusion that a God created the universe, scientists developed a very irrational theory that there are billions of other universes, or that evolution started on another planet which then seeded the earth. Have fun trying to build up enough faith to believe that.

              • Matt says

                I am very curious how you reconcile evolution and Genesis. Since there were no “First humans”, but an evolution of a group of humans evolving over time, there was no adam and eve, no adam and even, no original sin, no original sin, no need for a savior. The whole idea of needing forgiveness is because of original sin. One would have to create some very interesting ideas not from scripture, to reconcile these in my opinon(Such as “adam and eve” being a symbol of humanity, etc. which has no biblical basis)

                • tom says

                  As a Theologian and student of philosophy and the sciences, I can say that there is substantial proof that this universe began c.13.7 billion years ago, as we count time. This universe is continuing to evolve at the speed of light. Genesis uses the known cosmology of its time. The two creation stories are in the genre of myth. They in no way speak of a creation ex-nihilo. “God” creates from something that exists already.Just as grains evolved in our diet.

          • Mathieu Powell says

            I’m sorry, Rev., but every unfolding discovery of biological science supports evolution. There is no such thing as a “fact” in science, by the way. There are theories that best support the evidence we have found. Any particular theory remains valid until the evidence disproves it. Every theory must undergo the scrutiny of “null hypothesis”. That is why scientific discovery will never end.

        • Richard says

          1000 to 2000 years ago it is likely that it was warmer than today. How much human influence is melting the ice caps I do not know any more than you do…
          I do know that if people would change to a whole plant-based diet reducing animal production would have a larger impact than eliminating all modes of transportation not to mention the savings in water and land.

    • JoeTexas says

      Read the book. I had diabetes 11 years ago and the hemotologist told me to quit eating carbs or I would die an early death because the body converts carbs to sugar. I quit all carbs and in three months no longer had diabetes. Dr. Perlmutter has brought together the enormous amount of research done over the past 15 years and backs up everything he says with research from places like the Mayo clinic, Johns Hopkins, Harvard medical, and cites articles in the leading journals of the world. We now know that carbs also cause Alzheimers, heart disease, Parkinsons, and lot of other nasty stuff. Go ahead and keep eating them if you want, but they will destroy your brain and body.

    • Roy Walker says

      Not so much carbs are bad for us, but too many carbs are bad for some of us, especially fast acting carbs. The cemeteries would be filled to the brim if it were not for medical intervention, think about diabetes, in its many forms, if it were not for insulin injections,where else would they be, but in a grave.

  2. Midgy says

    I just finished reading the book last week and “my” takeaway wasn’t that carbs cause neurological disorders, it was that gluten causes neurological disorders. And that too many carbs from sugar, fruit, etc. (mainly high insulin and high blood sugar) increases your chances of alzeimers and dementia.

    Love your blog by the way!!

    • Chris Kresser says

      There’s no evidence that too many carbs from fruit increase the risk of neurological disease. From sugar, yes, but not fruit or starchy plants like sweet potatoes (that I’m aware of, at least. I’d like to see any if it exists.)

      • Mike says

        What about the point that fruits and other plants were seasonal and now we have them all year round. Fruits have way more sugar content now. Did you read Grain Brain?

        • Marc says

          Even more important, fruit has been re engineered to be much sweeter and softer than it ever was in the wild. We are probably not well adapted to fruit this sweet. Ancient fruit was much smaller, far more fibrous and as much sour as it was sweet.
          I think we are adapted to eating some carbs because we are opportunists and can eat a wide variety of foods. That does not make carbs optimal as food, only possible to be eaten as food. More likely our ancestors remained in a nutritional keotgenic state for as long as meat, fish and eggs were abundantly available. Perhaps during hard times they could switch to glucose for energy and scrounge up plants tubers and fruits.

            • says

              Dear Joel, the article that you provided a link to is very interesting. It should be pointed out that this paper presents a biased view on fruits (wild vs. cultivated) by examining a selection of fruits that fit the author’s thesis. I can list many, many more fruits that do follow the pattern of the wild version being smaller, and/or having more fiber (hence less sugar in the entire mass of fruit), and/or having a more bitter taste. Certainly these are generalizations and their are exceptions (as the author has focused on). His pie charts are misleading as he notes the carbohydrate content without noting that many of these carbohydrates do not contribute to sweetness. While it is good to be aware that stating wild fruits are smaller (or whatever) is not a hard and fast rule, generally speaking, those found in US grocery stores are larger, sweeter, with less beneficial phytochemicals, lower antioxidant content, less fiber, and less nutrition than their wild counterparts. Again, I do appreciate this link as it provides some nice exceptions. Best wishes.

          • Diane Lewis says

            I disagree. Wild tropical fruits are large and sweet, and our sweet tooth suggests that we naturally desire a certain amount of carbs in our diet. Nutritional ketosis let us survive in places where fruits and tubers were not year round, so it’s a great thing, but I don’t think we can say that modern fruit is a problem. I would say modern fruit is just mimicking tropical fruits. Refined sugar and grains, now, those are a problem…

        • BrittDoc says

          What about those things? How does the fact that we can eat most types of fruit year round change the fact that fruit has NEVER been scientifically linked to Alzheimer’s or dementia? Don’t buy into the hysteria- the theories in this book, surrounding fruit especially, are 100% baseless. Have you read the thousands of articles/journals/studies proving fruit is essential to obtain many of our micronutrients? Telling anyone to cut down drastically on their fruit intake (unless it’s incredibly high to begin with) when they have no proof it will be beneficial is ridiculous. We should cut out one of the only three macros we need to live because one guy has a theory, starving ourselves of micronutrients along the way? And vegetables are largely carbs, too. So we should all revert back to the failed fad Atkins diet then? Load ourselves with protein and fat, and pretend we don’t need the vitamins and minerals that keep our bodies going? This book is a dangerous mistake, because far too many people will see “M.D.” After a name and believe every word that person has to say, regardless of its implications. I’m a physician. A brand new physician that doesn’t know the vast majority of what people think I should know (that goes for all new docs by the way- I’d like to think I’m not a total moron or a really crappy doctor). I’m smart enough to know that I will NEVER know everything my patients expect me to know. Please, people, don’t believe completely baseless claims just because the person stating them went to school for an extra four years after college. The fact that people put so much stock into this nonsense scares me to death.

          • Bruce Wilson says

            So we shouldn’t necessarily listen to an M.D. (logical fallacy: appeal to authority), but yet we should listen to ” thousands of articles/journals/studies proving fruit is essential to obtain many of our micronutrients” which itself is an appeal to authority. Last I checked, Atkins is not a failed diet, and proves you know nothing about it. Atkins advocated eating lots of veggies and never said not to eat fruit.

            What failed was the popular misrepresentation of his diet, pushed by fast food corporations and his detractors.

            • Richard says

              There is no long term study on the Atkins diet that shows it can reverse disease as some other diets can.
              The longest study on Atkins was one year and the average weight loss was less than 5%. If your goal is to lose weight for one to three months you might do well on Atkins….

              • Brad Steinemann says

                Hi Richard, Do not know where you get your information on Atkins. People that got on diet and kept on it lost alot of weight. I lost alot on it, I went from 215 to 176. I think that is more then your 5%. Everyone I knew who went on diet lost alot of weight. Please research more before you make uneducated comments.

          • Roy Walker says

            Britt Doc Fruit, or Carbs, is not necessary to our survival, Protein and fat, yes but not carbohydrates. we can not make protein in the body, we need it to survive. we can not make all the fatty acids. We need fat. We can make glucose, we don’t need to ingest them. Will we thrive without carbs, that is an unanswered question, but a lot of evidence is pointing to maybe, yes.

          • Mona brooks says

            If everyone had actually read the book, we would not be making such wild accusations about what Dr Perlmutter has to say.

      • Ann says

        I had a history of neurological problems, including epilepsy. Meds never worked and surgery in 2005 stopped my seizures. In 2009, I was no longer able to lift my arm. I went to many MDs, who suggested therapy or surgery. When I learned about histamine intolerance there was something called frozen shoulder caused by reactions to citrus fruit. I stopped all citrus consumption (2013) and my arm began working again within 3 weeks. No meds, no surgery, and PT never worked. Stopping eating oranges and tangerines did. I had started to cut out food with histamines in September 2012. I have not fainted since then (which is the first time I have gone more than a few months without fainting since 1970).

        • Leslie says

          I have frozen shoulder. I almost never eat citrus, and I’ve never heard this ridiculous theory before. Sorry, this was a placebo and frozen shoulder heals after about a year on its own.

          • Bruce Wilson says

            I have heard of this in relation to my mother. She was having pain in her joints and she cut out citrus and the pain went away. It has to do more with citrus picked green.

            Just because you never heard of it before doesn’t mean its ridiculous. Perhaps you should do some research before shooting off your mouth.

            • Leslie says

              Had frozen shoulder twice, and have done tons of research. If you google this, one random site claims there is a connection.

              Pain in joints is not frozen shoulder, so I’ve never researched that. Perhaps you should consider they are different conditions before YOU shoot off your mouth.

              Have a great day!

        • Richard says

          I had frozen shoulder for years and bought a speed bag platform about five years ago. I stretch and use the speed bag for 30 minutes three times a week.
          I eat about six to ten servings of fruits along with the rest of my whole plant-based diet and have not had shoulder problems for years now…
          I am happy your shoulder problem is gone but I doubt it was ever due to the fruits you consumed.

      • Kurt says

        Chris and others, I’d recommend that you read a very interesting take on fructose published earlier this year by Dr. Richard Johnson, The Fat Switch. Dr. Johnson is a renal expert teaching at the University of Colorado. Very interesting stuff on the effect of fructose.

      • Steve says

        Did you read the book Perfect Health Diet by Paul Jaminet? Their diet is a moderate carb, high healthy fat diet. They mentioned eating roughly 1 pound of safe starches such as potatoes, white rice, sweet potatoes and 1 pound of healthy sugar plants such as carrots, raspberries, bananas, beets. Also protein is eaten roughly at 0.5-1lb per day.

        Their diet tries to maximize nutrients and minimize toxins. So to reduce the quick rise in blood sugar they would use starchy carbs by boiling the potatoes, eat them with an acid such as vinegar, and a fat such as butter to blunt the spike in glucose response in the body.

        The healthy sugary plants should be optimized for high potassium and low fructose ratio. Fructose is shunted by the portal vein in the liver and can be problem above a 100 calories a day according to their book. Fructose can change blood lipid and cause other harmful problems. Fructose comes from two main sources fruit and high fructose corn syrup. In the case of most Americans the over dose of fructose is from the sweeteners used in the processed foods.

        I am just someone interested in learning and applying better health standards to myself and might not have translated Paul Jaminets idea correctly but it should be close enough for you to understand.

        Appreciate your information and keep up the good work.

      • Tom Boyer says

        Chris writes: “There’s no evidence that too many carbs from fruit increase the risk of neurological disease. From sugar, yes, but not fruit …”

        Thompson seedless grapes: 1 cup contains 23 grams of sugar, almost all of it in the form of fructose, which some people contend is the most toxic form of sugar.

        Banana — 1 medium size contains 28 grams of sugar — again mostly as fructose..

        One large orange — 17 grams of fructose.

        A 12-oz can of Sprite: 38 grams of sugar, either fructose or sucrose.

        How exactly could sugar in soda be harmful in myriad ways (which many people seem to accept) but sugar in fruit — which is EXACTLY THE SAME CHEMICAL COMPOUND — be harmless?

        Seems to me we are overdue for a reappraisal of the role fruit should play in our diet.

        I personally love fruit but we think of it as a dessert or a supporting ingredient. We do NOT think of it as health food. It is one step above cigarettes. I.e. we’ll enjoy an orange smoothie a few times a year as an indulgence. We’ll add a few tablespoons’ worth of mandarin orange to add a splash of sweetness to a salad.

        But given what we know about fructose and obesity, diabetes and pancreatic cancer, I can’t understand anybody recommending that people eat 4 or 5 servings of fruit a day. That just does not seem responsible to me.

        • beaker says

          Well, there is something fruit has that straight sugar doesn’t.. 100′s of chemical compounds and fibre that go with it. Those same compounds and fibre feed the gut biome which in turn does a lot of the processing of the fructose. It’s likely high “dead” sugar intake weakens or destroys the biome, causing a dysbiosis that makes further sugar intake detrimental. Future science will be based a great deal on the human microbiome.

        • Robbie says

          Hi Tom,

          Looking at fruit as something to indulge in could be seen as one way of looking at things. Others may argue that it is much more than that.
          I would certainly not compare it to a cigarette.

          One mistake in your assumption is that fructose in fruit is the same as fructose that is chemically derived or from processing food. Yes, chemically, it looks the same, but it does not behave the same way.

          Have a look at this video:

          This guy makes the distinction between those two (although, he mostly speaks about the bad fructose)

          Also, if you look at scientific evidence, you can find that humans are physiologically build like frugivores.

          Two references:
          Have a look at the table

          I hope you have an open mind.

          The healing I have seen once people switch to a fruit diet is just amazing.

          best regards,


        • BrittDoc says

          Tom Boyer, you are very confused about sugar. I don’t want to get into the biochemistry, or the types of sugar that exist, but your notion that fruit and Sprite are the same regarding sugar and fructose being toxic (so not even remotely true nor does it make any kind of sense) is just incorrect. Refined sugar and the sugar that appears naturally in fruit are NOT THE SAME. not even close. Again, the complex biochemical explanation isn’t something I’ll get into, but refined sugar is the only type of sugar that MAY have some link to neuro disorders, but we don’t even know if that’s a factor in reality. Fruit is rich in micronutrients and to cut it out of your diet because one doctor theorizes it may cause neurological disease is ridiculous. You are doing yourself a huge disservice if you avoid fruit because you think it is remotely similar to refined sugar.

        • BrittDoc says

          Yes, Tom Boyer, I’m extremely confident. Confident about my knowledge of biochemistry, in which I possess a college degree, and confident that you have jumped on the hype train and didn’t have the essential basic knowledge of biochemistry before you did so. To essentially say eating fruit and drinking Sprite or eating candy is the same thing is unbelievably foolish and the opposite has been proven so many times it’s ridiculous to believe otherwise. Your theory is just conveniently sidestepping the fact that fruit has fiber, which causes it’s sugar to absorb into the body slower. And “dont tell you about micronutrients”?! Um, that’s the whole point! So you’re saying the fact that fruit offers multiple micronutrients that are essential to healthy physiological function is not important when comparing it to processed sugar?? Huh? Let’s see… Fruits have super nutrients and phytochemicals that no one can argue benefit the body tremendously. Your Sprite example has nothing of value. You’re acting as though nutrients don’t matter, but the TRUTH is that they can change the way the sugar is processed in the body. I think you should read up on the well-established science that has proven beyond a doubt that you’re wrong and stop obsessing over new, unfounded studies. If you had the level of biochemical training I happen to have, you would know that what you’re saying it just completely false.

      • Danny says

        But these ‘safe’ carbohydrates you speak of, they get converted into sugar (glucose) and then enter the bloodstream. As the research shows, all glucose (including the glucose converted from fructose and fruits) when taken in doses over 60g in human testing cause inflammation in tissue. Namely brain tissue. I think you might want to actually read the book a few times before posting a response. Check the research at the back of the book, when you actually check it you’ll realise that this is irrefutable. The absolute main point to REMEMBER and fully consider now, is the delay in cause and effect between ingesting diets moderate or high in carbohydrates. No symptoms? No worries? Well no. Whether you realise it now or later on when it sinks in, if you continue with the carbs, the ‘EFFECT’ will definitely catch up to you and you will wish you had of sat up and read the research. -Do the research on inflammation studies

        • BrittDoc says

          Danny, irrefutable?! Hardly. Food research such as this that is taken out of context is NOT the end-all-be-all. There have been so many erroneous food studies that claimed to “prove” one thing or another and were actually DISproven shortly thereafter, I can name about fifteen off the top of my head. Don’t believe everything you hear because “a study was done”. The bottom line is that fruit provides a huge percentage of multiple micronutrients we need to survive. To compare them in any way, including the effect of their sugars, to refined junk is preposterous. And to cut them out of your diet is doing yourself a huge disservice. Whole, unrefined food is good food. That’s the very simple underlying fact that people tend to forget in all of these trendy, alarmist food fads.

      • Chris says

        Just started reading the book with my wife, but to your statement shouldn’t someone i.e. type ii diabetic be concerned about any forms for sugar be it natural or not? If a diabetic should, then from reading what I have read, I can draw a correlation between giving my body too much (sugar, natural or not) before diagnosis thereby creating the sensitivity in the first place?

      • Debbie says

        Okay, but if you eat too many starchy vegetables and sweet potato at one sitting, would that cause a blood sugar spike – in someone with metabolic derangement?

    • Marlayna Tuiasosopo says

      Yes, this blog post is focusing on fruit as the reason why the author’s arguments are somewhat faulty, but the book is more focused on gluten/whole grains.

  3. Edle M Andersen says

    I have read Grain Brain and came to the same conclusion you did, great as a therapy if you have serious problems.
    What I am wondering about is that I had my gallbladder removed 30 years ago, it has not been a problem for me, but I am concerned that eating a “high fat diet” my cause some problems in the long run.
    would love to hear your feedback on this

    thank you

    • Honora says

      Maybe consuming ox bile at meal times would be a work-around for the fact that you no longer have the reservoir to hold a back-log of bile in preparation for when you consume a meal and fatty acid and protein are detected.

      Without the gall bladder, the common bile duct is now draining bile via the sphincter of oddi but if the sphincter of oddi is normally closed off in the interdigestive phase, I’m not sure now the body copes with a build-up of bile in the common bile duct and how that affects the liver which actually produces the bile. Methinks I’ll have to hit the A&P sites some more…unless someone has the answer to that one for me. The sites have said that post-cholecystectomy the CBD drains the bile into the duodenum continuously but I’m not sure if that’s the case if the sphincter of oddi remains contracted in the interdigestive phase. Perhaps the pressure of not having a reservoir increases the flow of bile against the sphincter of oddi. I could ask the maestro of CBD surgery here in NZ (Saxon Connor).

  4. says

    Great Stuff Chris! I think in general a low carbohydrate diet is good, but the very low carb diet may be too restrictive for long term success. There are simply too many good nutrients in fruits and vegetables that people need for good health.

    When most people think of carbs they think of breads and pastas. These are the carbs to remove for good health and they are the ones causing the “Grain Brain”. Most people today get all of their carbs from these sources, so lowering them will be beneficial. Too many people on VLC diets are not eating enough veggies (worrying about their carb content) and this is probably where they go wrong.

    I also think there is good value in cyclical ketogenic diets, with starches saved for 1-2 days per week post excerise. I don’t think you would see the same long term disadvatages while maintaining many of the benefits.

    • Chris Kresser says

      I agree that in the mainstream most people thing of breads and pastas when they think of carbs. However, the whole reason I wrote this article is that I’ve had several patients coming to me expressing concern that they are putting themselves at risk by eating more than 60 grams of carbs a day in the form of starchy plants and fruit. And I’ve received many questions via my website contact form along the same lines. That’s why I think it’s so important to be clear with these kinds of recommendations.

      • Diane Lewis says

        I hear ya. I read the book and I’ve been paleo/primal for a while… I thought, and commented on Mark’s forums, that the carb intake he advocates is extremely low. I’ve done ketosis before and it was fine but as a way of life I find it irritating and unnecessary. I’d hate to think about people stressing because they’re going over 60 grams of carbs…

      • Kurt says

        Chris, 60 grams of digestible carbs is not very low. That’s equivalent to 4 slices of bread a day! My heavens, Chris. 4 slices of bread equivalent is not very low, nor a horrible deficiency. If I recall correctly (pulling from memory rather than checking their book) Drs. Jaminet and Jaminet in their recent book, Perfect Health Diet, establish carb toxicity levels above 150 grams, with optimal below that. Sometimes too much is made of select genetic populations that have evolved to eat one way or the other and, while informative of overall human diversity, that information is not necessarily valid for all human populations.

      • Bruce Wilson says

        When I read your article, it did seem to start out to debunk Dr. Perlmutter, by characterizing his advice as a low carb diet. It then introduced points to rebut low carb diets. My understanding of Dr. Perlmutter’s recommendation is that he is not just a low carb advocate. He allows for 60 carbs in his diet, and the preference is that the carbs come not from whole grains such as wheat. The points in your article are about people subsisting on starchy roots, not whole grains. I would recommend a rewrite, because as it stands this reads like deliberate mischaracterization of Dr. Perlmutter’s position (who is also an MD) and a bait and switch. Perhaps a more accurate description of what Dr. Perlmutter actually recommends (with citations) and examples of healthy people with diets of 80% wheat in their diet.

      • Bob McConnell says

        Could you do something about the comments that are complete BS, or at least unsupported by any current and rational scientific research? Also, you should probably require people who write comments to at least state their qualifications. Too many people are writing as if they were doctors or researchers when they are not.
        Bob McConnell

        • Marc says

          We really dont want to listen exclusively to Doctor’s anymore or professional nutritionists or researchers… Fool me once shame on you, fool me twice, shame on me.

          Experts will cling to a dogma they are invested in long past the time they should have dropped it.

          Ordinary people taken as a collective whole have far more valuable information except that it is more defuse.

          The days when Doctor’s and Experts lead us down the road to soaring obesity rates and soaring rates of disease are ending.

          So sale
          I once had a candidate for Mayor knock on my door to get my vote. He told me his idea’s and then proudly proclaimed that he was a lawyer.. I stopped him in his tracks and told him I prefer not to vote for lawyers.
          He didnt know what to say.


    • Marc says

      There is no essential need in the human diet for carbohydrate, none at all. You can go your entire life and never eat a single fruit or plant or tuber and have optimal health and longevity. These foods may just be supplemental to our most natural diet. Plants really are not packed with as many nutrients as commonly believed especially coming from depleted soil. They do have good antioxidants and fiber but nothing all that special. If you eat too many sugary fruits and carb rich potatoes and such the like you will without doubt increase your insulin levels. Insulin should be kept as low as possible for optimal brain health, longevity and overall good health. High carb intake may shrink brain size and is glycating.

      • Aaron B says

        There is definitely a need for carbohydrates Mark. I was told to go on a no carb diet and saw very bad results as my body went into a severe stage of ketosis, followed by metabolic catabolism. Not to mention that (good carbohydrates) are a good source of energy. If zero carb diets were any good people would be still be raving over the Atkins diet not ranting about it!

        • Marc says

          Unless you are a type one diabetic you may have miss diagnosed yourself. People who are type one diabetic can’t make any insulin and can go into what is called “Ketoacidosis”, a very sever overload of ketones. That cant happen in a normally healthy person just by keeping your carbs low. Instead, you will change your metabolism and become adapted to burning fat for energy rather than sugar ( glucose). Both your brain and your body work more efficiently burning fat. Babies for example are naturally in ketosis if they breast feed right up until the moment their parents start feeding them carbs. Human breast milk is very high in saturated fat.

          Your body naturally produces all the glucose you will ever need and can store about 2,000 calories worth of it in your liver. You never need to eat a single carb. That is what an “essential” nutrient is, something we cant make on our own and need to eat. We can make all the glucose we need without out ever eating a single carb. Therefore, by definition carbs are not essential.

          I dont know you but if you got sick dropping your carb load there can be several reasons for that. After a lifetime of eating carbs/sugar people sometimes need to help their digestive system come back to life ( with pro biotics or fermented foods) so it can once again digest fat properly.

          • Megan Oien says

            BreastmilK is actually a high carbohydrate food-40% carbs- mostly milk sugars that is what makes it sweet.
            I have been very sick by going too low carb- resulting in thyroid and adrenal issues. What works for one person doesn’t work for another. And even the same individual has varying carbohydrate needs at different points in their life. As a nursing mother of three, I need a moderate amount of carbs. My husband can go low. My kids needs change with their age. Listen to your body.

            • Terance says

              I appreciate your input. I Believe you are correct as we do change biologically in our nutritional needs any to tolerate complex or simple carbs or sugars depending on our health status, that is starting with digestive health then leading to mental health.

            • Bruce Wilson says

              “Mature human milk contains 3%–5% fat, 0.8%–0.9% protein, 6.9%–7.2% carbohydrate calculated as lactose, and 0.2% mineral constituents expressed as ash. Its energy content is 60–75 kcal/100 ml. Protein content is markedly higher and carbohydrate content lower in colostrum than in mature milk. Fat content does not vary consistently during lactation but exhibits large diurnal variations and increases during the course of each nursing.”

              • says

                You know that’s by weight right? I think Megan was referring to the percent of calories in milk that come from carbohydrate.

                Whole milk is around 30% carbohydrate, 20% protein, and 50% fat as a percentage of calories (see USDA data below)

                Nutrition Facts
                Milk, whole, 3.25% fat
                Amount Per 1 cup:
                Calories 148
                Total Fat 8 g
                Total Carbohydrate 12 g
                Protein 8 g

                • Bruce Wilson says

                  “Lactose is the primary carbohydrate found in human milk. It accounts for approximately 40% of the total calories provided by breast milk. Lactose helps to decrease the amount of unhealthy bacteria in the stomach, which improves the absorption of calcium, phosphorus, and magnesium. It helps to fight disease and promotes the growth of healthy bacteria in the stomach. ”

                  So actually Megan was probably referring to calories. Which of course means 60% of the calories are coming from fats and protein.

              • Megan Oien says

                Breastmilk changes in macronutrient ratios depending on many factors, which include: baby’s age, time of day of nursing, nutritional status of mother, the fullness of the mother’s breast (fattier hindmilk clings to milk ducts and is not released to the end of a nursing), among others. On average lactose and oligosaccharides account for 37% of the total content.

                So, if we extend that to the adult population as Marc alludes to above… A 2,000 calorie diet, at 37% carbohydrate, would be 740 calories or 185g carbohydrate. This is more than three times what Dr Perlmutter is recommending.

                I just don’t believe that babies are in ketosis until they ingest their first solid food carbohydrate, like Marc states above. This is mininformation. And, I think every individual has to decide what carb level they feel best at. I think 60 grams is awfully low and unsustainable in the long term, because it can lead to major deficiencies. I’d hate to see the Paleo community go in this direction.

            • mackie wesley says

              I tried the grain brain reduction in carbs for several weeks, felt lousy (headaches, fatigue, and bloated) I guess that can be expected. I will continue to watch my carb intake, but making something the forbidden fruit usually leads to disaster…craving it, and overeating it later on

          • Eileen says

            Marc, you’re a good one to ask. What’s the story on VLC causing hair loss in some people? Read a good many accounts re Adkin’s diet. And not the hair loss that comes from rapid weight loss either. Seems there are people who report going on a VLC diet with no weight to lose and after a period their hair starts to thin.

          • Richard says

            The studies are not always about whole foods and that makes the results questionable.
            I eat raw garlic and onions but looking at only one chemical in garlic is not a scientific answer to what the whole food does to me.
            Grains have to be processed before cooking by at least soaking if not fermenting/sprouting followed by cooking. To look at the impact of eating whole unprocessed but cooked oatmeal is not going to result in what happens when I eat my oatmeal after soaking for 24 hours and fermenting it for another 24.
            Applying common sense by recognizing all the bad stuff in meat which is not the same as it was 100 years ago motivated me to a whole plant-based diet. I do not need any more studies to tell me I do not wish to eat farmed-fish or contaminated meat.

        • Ronson pickles says

          The ketogenic diet by Lyle McDonald, a great book but being in heavy ketosis can mess you up badly if done long term.. More damage then good

        • Tom Boyer says

          People who have felt bad trying low-carb diets are almost always feeling the effects of lower blood pressure and sometimes lower blood sugar. Both of those are good things but they can make you feel faint and queasy while your body adjusts.

          No one should try very low carb without some research — the “New Atkins” book is a really excellent and scientifically excellent starting point — edited by Eric Westman of Duke University Medical Center.

          If you have any kind of complex health issues you should try to involve your doctor — and if your doctor refuses to cooperate, and his/her reasons to say no don’t make sense to you, find another doctor.

          When you go low carb, the first thing that happens is you lose 4-6 pounds of fluid. There are two theories about that — one theory is that your body needs more fluid to digest carbs. The alternate, very intriguing theory, expounded by Perlmutter, is that the extra water weight is simply an inflammatory response to carbs, particularly to grains and sugars.

          In any case, when you lose that water weight, your blood pressure can go down quite dramatically and people feel lousy from hypotension and mild hypoglycemia. Fortunately there is an EXTREMELY easy cure for this — drink something salty, like chicken broth. It will stabilize your blood pressure while your body is making the adjustment to low carb. It works in nearly all cases where people are feeling bad on a low-carb diet.

          Often in a few weeks, as they lose water weight and then burn off a bunch of fat, people’s blood pressure stabilizes at a much lower level and they can come off their blood pressure meds, which is one nice benefit of low carb eating. Another really nice benefit which almost everybody experiences is that acid reflux simply disappears — often in a few days. So people who are basically permanent users of Prilosec or Zantac can come off them — which is really good because there is more and more concern about long term side effects from those drugs.

          The confusion between ketosis (fat burning) and ketoacidosis (a very serious condition suffered by diabetics in very late stages of the disease) I am not going to get into here, but any doctor who is still confused about that ought to turn into his/her medical license. Ketosis is safe for almost everybody, and virtually everybody does it to some degree every time they go 6-8 hours without food..

          • Patti says

            I love the way people determine that they know what is best for others and they tell you how you will respond to following a certain diet. I did fine with low carb at first, but as the months wore on, I felt TERRIBLE. I lost energy, had dry eyes and skin…my thyroid was withering and my metabolism was bottoming out. Increasing carbs IMPROVED my health tremendously. I know what works for MY body. We are all different. Don’t try to tell me what I need!

          • Brittdoc says

            Tom Boyer, for the last time, you have zero evidence to back up your claim. Evidence would be controlled medical studies performed by a legitimate source, published in a respected medical journal. A guy with a theory is just that. It’s useless, especially when it goes against the thousands of published studies already done. Go on believing every alarmist headline you read. It will undoubtedly drive you crazy. I am not exiting gracefully out of this forum, as I am not going to waste another moment arguing against nonsense.

          • Richard says

            Why would I want to try a low-carb diet when I know how good greens, legumes, fruits and other vegetables are for me?
            Meat has protein and B12 but kale, watercress, broccoli, berries, garlic and onions have thousands of known good things in them and likely many more thousands yet unknown…

            • Marcelo says

              Richard, according to perlmutter, people should eat garlic, onions and broccoli – but avoid carbs coming from grains or pasta. A low carb diet allows you to eat up to 60g of carbs/day – and there’s room for a lot of broccoli here

      • says

        You’re very incorrect in this, Marc. The body’s energy supply requires carbs to supply energy in cases of explosive energy need. Fats CANNOT supply explosive energy. Below 45% VOX2 MAX, fats are moreorless exclusively used to drive energy. Above 70% VOX2 MAX, it’s exclusively glucose primarily from glycogen. In between is a sliding variable scale. That’s why humans have between 300 – 700 grams of glycogen stored – for explosive energy. This regularly has to be maintained, so carbs are needed in an optimal world. Fats do fine for most of our energy needs, but not all.

        • Tom Boyer says

          Arguments that “explosive energy” can only come from a carbohydrate diet have been pretty well debunked. Look up the work of Jeff Volek and the scientifically rigorous blog of Dr. Peter Attia. Very low carb is actually a great regimen for people who exercise a lot (ask the LA Lakers whose training regimen is now low carb).

          Last time I read Attia, he was exploring the idea that carbs may provide a marginal benefit in sprint-type events. But for anything of distance/endurance, people seem to perform better, not worse, on VLC. The theory being that ketones are simply a better fuel than glucose and glycogen. The metaphor is that carbs are like burning paper, or maybe a marshmallow, and ketones are more like burning wood, or maybe lamp oil. Ketones provide a steadier and more efficient source of fuel.

          In my personal experience as a low-carb eater, I don’t get the “hit the wall/second wind” experience when I ride my bike. I just start out feeling like “second wind” and I don’t hit the wall at all. I don’t do long rides — maybe 20 miles — but my level of fatigue while riding is dramatically lower when I am limiting carbs.

          • Richard says

            Energy your whole focus? What about fighting cancer and clean arteries? I do not want to go through one day without lots of greens, beans, fruits and other vegetables joined together with raw garlic and onions!
            That kale is going to save my eyes when I am 80 lol

            • Marcelo says

              As I said in a previous comment, garlic, greens and such are allowed according to Perlmutter, and cereals and bread should be avoided

              • beakernz says

                I do not advocate any grains, but I do advocate processed grains. There is a HUGE difference. People need to wake the hell up and stop comparing the two as equals. All my grains, breads, pastas are fermented a min 48hrs in sourdough cultures. All this harsh aspect of grains many complain about are GONE, pre-digested by the bacterial culture. Not only that but these processed grains have increased nutrients and virtually no phytates. To deny your body a food group because you are too lazy to prepare it properly is absurd. Perlmutter needs to fully investigate long fermented grains. I’m 41, 5-11 165lbs all muscle. Have had full cardio workup and bloods, doc puts me in top 3% of health. He even claimed “some of your numbers are that of a healthy 16yr old, keep it up”. I also intermittent fast 16hrs a day. You will improve all health markers by intermittent fasting far far more than by going grain free. So in summary, when people here discuss grains please make a distinction and call them “unprocessed grains”.

                • Marcelo says

                  ” doc puts me in top 3% of health.”

                  Wow, and did he analyze your brain, too? Because that’s the main damaged organ according do Perlmutter. Actually, that’s what his book is about, the link between grains and neurocognitive distorders.

                  ” To deny your body a food group because you are too lazy to prepare it properly is absurd.”

                  Perlmutter makes very clear that “he human requirement for dietary carbohydrate is none, none whatsoever.”

                  And if you think Dr. Perlmutter didn’t do his research very well, I should tell you that he’s not the only respected doctor that warns us about the risks of grain. Previously to him, another famous MD was a guest to Dr. Oz, he told the audience that carbs are bad for you. Oz was clearly skeptycal about his statements, but later he had D. Perlmutter as a guest, he said the same things and Oz knew at that moment he was wrong all the time. You think all the researchers who think grains are bad for you forgot to take into account the differences between the grains?

                  PS: english is not my native language

                • beakernz says

                  I’ve never seen a single ‘anti-grain’ researcher mention long fermented sourdoughs or what happens to grain when it is processed properly. If they did that, how would they make any money and sell books or get on talk shows? I come from a family where most if not all of my relatives live past 87 and have phenomenal mental performance for their ages. No trace of parkinsons or alzheimers and I can assure you they eat grains and carbs. My grandmother is 93 years old, still drives and still works part time. She is like a 65yr old. I sat down and went over her diet (because, sure, I want to know her secret!). It turns out she skips breakfast everyday and has an early dinner. She has unknowingly been intermittent fasting for the last 40yrs. I’ll say it again, intermittent fasting will improve brain condition and health markers FAR more than any diet could. FAR FAR more. When in the fasted state the organism boosts and protects the brain in a variety of ways. Why? Because the organism wants you to be capable of finding food! It’s so simple. Eat a healthy varied diet but only 8hrs a day feed window. That is all that is required for optimal health -but it’s far from entertaining.. the people want their fad diets, diet gurus and diet bloggers so will be left in the dark about the real way to be healthful.

                • Marcelo says

                  It seems like you don’t know what you’re talking about, you have no data to back up your statement.

                  Your mother is 93, and you found that she’s been fastening for 40 years but do you know any person who tried perlmutter’s recommended diet for such a long time to tell how long this person lived, and thus which diet is more efficient? I don’t think so.

                  Also, Dr. Perlmutter advocates fastening


      • Patti says

        Carbohydrates are so essential to the body that the body will produce them if the diet does not contain an adequate amount. That does not mean that low carb dieting is optimal. There are certain functions in the body that REQUIRE glucose. When I stayed under 100 carbs a day, my energy levels dropped, I was cold all the time and I just felt awful overall. Increasing carbs has resulted in many health improvements for me. No one can tell me my body doesn’t need carbs. It does. And I am a 52 year old female in generally good health.

        • says

          From my experience, I have worked 10 hour shifts with complete ease while eating pretty much keeping below 60 g of carbs. I used to walk basically all day long and carry boxes weighing in some cases up to 50 pounds. I figured I walked on average 15-20 miles per day for 5 days a week, averaging about 75-100 miles per week. Most of the people I would ask them what they ate for breakfast that were the most likely to quit or take breaks or complain the loudest about all the walking required of the job often told me that they ate large breakfasts, juice, toast, cereal, fruits and maybe some eggs, but they usually never could keep up with the work, some were large and muscular, looking pretty fit, but complained regularly. I hardly ever felt tired nor winded by any of the work, I would usually eat at most 2-3 eggs with some bacon for breakfast. That was all. Recently I went off this diet and went from 165 to 225, not walking or exercising just eating carbs and whatever I felt like, When I did a low carb diet in 2006 I went from 250 to 165 over the course of 12 months, that enabled me to work that job. Anyways recently I have gone back on the diet dropped down to 195 from 225 (had inflammation, allergy problems with nasal polyposis, sedentary and carb consuming), now my allergies are clearing up no polyps issues, My reasons were not weight this time around though I did need to lose some, I just wanted to stop the inflammation. Now I can run 5k almost not breaking a sweat, not feeling tired afterwards, prior to cutting carbs running 5k was an ordeal, tiring and painful. Of course losing weight has helped, but while eating any carbs I wanted and exercising I was going nowhere, lifting weight and jogging, my weight would not budge nor would my polyps shrink, I cut wheat out and within the past 3 months my system has been relentlessly shedding the excess and the polyps have stayed put not to block my airway!

          • Tom Boyer says

            Good post, thank you Joe. It’s funny, the people most distainful of LCHF approach are invariably the people who know least about it — and usually have no desire to learn the facts. People who have firsthand or secondhand experience with it seem to range from mildly favorable to ecstatic.

            • Patti says

              I actually know a LOT about LCHF. And it DIDN’T work for me. Why do some people have such a hard time accepting that?!

              • Patti says

                And I also know of a LOT of people who have had negative experiences with LCHF over time. People who did it for months and then started experiencing symptoms of low thyroid/metabolism.

          • Patti says

            Good for you. However, that was not my experience. We are all different. What works for one, does not necessarily work for another. Low carb did NOT work for me.
            Also, I do not eat junk carbs. I eat potatoes, sweet potatoes and white rice (per the Perfect Health Diet) as my main sources of carbohydrate, along with 2-3 servings of fruit most days. My carbs come from real, whole foods, NOT processed crap. There is a HUGE difference in impact on health from real food or processed foods. Don’t blame carbs if you feel awful eating processed foods.

            • Bruce Wilson says

              White rice is simply starch. Would you consider corn starch a “quality” carb? I don’t think one can seriously make a distinction between the two. Any chemists care to enlighten us?

        • Richard says

          Your body is not going to produce all that great stuff in watercress, kale and other fruits and vegetables….you are deceiving yourself!

      • BrittDoc says

        Sure Marc, you can survive without carbs….for a shorter time than those who fill their diet with starchy plants and fruit. Where did you get this information from? You can survive on twinkies if you wanted to. And you would get I’ll more frequently, and be in general poorer health, just as you would if you cut out carbs completely. If you were familiar with biochemistry, you would know that this is a totally erroneous theory.

  5. Nathan says

    I read Grain Brain but this is hitting home. My thyroid levels were on the high side of normal after following a low carb diet for a while. Very interesting.

  6. Phillip Shanks DC says

    Yes have read Grain Brain and also heard Dr P speak recently here in the Denver area. I believe his book reflects good clinic observation and a balanced reliance on current refereed journal articles and research. He is biased in his patient population and the extrapolation to the general public may be a stretch. However lets not throw his work under the bus either. If we as functional medicine practitioners can use this information and his extensive platform to get peoples attension then let’s use it. The message is stop consuming the most damaging carbs (hfcs, fake sugars and fats,gluten containing grains, processed dairy and rely on regionally grown in season fruits and veggies with good protein sources and good saturated fats. When you drill down this is his message. And I believe Chris it has been your message as well. Can’t wait to see you new book. Blessings Phillip

    • Chris Kresser says

      I am not throwing his work under the bus. As I said in the beginning of the article, there are absolutely situations where a VLC diet makes sense (and patients with existing neurological disease is one of them). But a diet that treats a particular condition isn’t necessarily required to prevent it.

      For example, low-carb diets can be helpful in the treatment of obesity, but contrary to some claims carbohydrates do not by themselves cause obesity. An autoimmune protocol which eliminates dairy, eggs and nightshades may help with existing autoimmune disease, but that doesn’t mean healthy people need to avoid these foods in order to prevent it.

      We have to be very careful about confusing causation and therapeutic effect.

      • says

        Yes, thank you! We do have to be careful not to confuse therapeutic effect with causation. VLC has been on my radar since attending the Portland Regional WAPF conference in September and listening to Nora Gedgaudas speak. She mentioned Perlmutter several times. I think the sweeping recommendation that everyone benefits from a ketogenic diet is actually dangerous. I have spoken to many people and personally experienced adrenal and thyroid issues while on GAPS that went too low carb. As a nursing mother of three, I need carbs. So I appreciate you pointing out that many traditional cultures thrive on high carb diets. I also think VLC diets can be very unnecessarily restrictive and unrealistic long term-resulting in failure.
        I have read your posts for years, never commented. I appreciate your unbiased approach.

      • Kurt says

        Chris, I beg to differ with you on your interpretation of your contribution in this very interesting and well thought through article. You are throwing Dr. Perlmutter under the bus. I too have questions about the extent of glucose effect on the body, good and bad. Dr. Perlmutter wrote his book after carefully reviewing 252 studies specific to the topic. In this your article, you take the thesis that a “theme” of eating that may be therapeutic is not necessarily preventative. Yet you neither qualify nor substantiate your theory. It makes good emotional reading for those who want their nerves on this issue calmed, which seems to be your motivation on behalf of your readers, but while I see general vague references, I don’t see any hard science in what you have pointed to that would ground the tone of your critique of Dr. Perlmutter. I like your earlier writings on cortisol and the effects of glucose need and request, and the interplay of epinepherine. Yes, Dr. Perlmutter made some strong statements, and drew some strong conclusions. My guts tell me that there is substantiable critique of him out there, but I would like to see pointed science rather than emotionally flavoured arguments.

      • Mary says

        So, are you actually saying that people should not be trying to prevent Alzheimer’s by lowering carb counts based on the evidence he presents and his clinical experience? People should only lower carb counts once they are actually diagnosed with Alzheimer’s?

  7. Jennifer says

    I think his carb recommendations are 40 for 1 month and 60 after that? It’s low, but not atkins introduction or keto low. He concedes that occasional splurges are fine and there will be holidays and special events. The message I got from his book is more about overall health than super strict carb police. I really enjoyed reading it and it made me rethink my sushi dinners that were becoming way too frequent.

  8. says

    Chris, I’m reading Grain Brain right now and it appears to me you’re misrepresenting what Perlmutter is saying. Not once has he suggested people eliminate carbohydrates from whole foods like vegetables and even totally from fruit. He targets grains generally, and wheat in particular. Hopefully this is just an oversight on your part (did you even read the book before you wrote this post?!?) and will be promptly corrected.

    • Chris Kresser says

      I have seen him suggest in several places that people should restrict carbohydrate intake to 60 grams a day, and that’s exactly how I represented his recommendation in the article.

      • Patti says

        Exactly. And after eating 50-60 grams of carbs a day for several months, I ended up with a depressed thyroid causing my energy level to plummet along with other effects. Increasing my carbs in the form of fruit and safe starches (AKA Perfect Health Diet – white rice, white potatoes, sweet potatoes, etc.) caused my energy to return and I feel so much better. Advocating such a low carb amount for the general population is a mistake, in my opinion. I know of several others who’ve had similar experiences, females in particular.

      • Kurt says

        Chris, at 4 slices of bread-equivalence a day, 60 grams of digestable carbohydrate is hardly a draconian restriction. If someone told me that I should only have 4 slices of bread, or 1.5 cups of rice with my daily eating, I wouldn’t say they’re telling me carbs are toxic! 60 grams of carbs daily also equates to 3 cups of butternut squash, 7.5 cups of spaghetti squash, 14 cups of cabbage, or 7.5 cups of carrots – or 24 cups of boiled spinach. To sound a bit silly but not out of the ballpark, I would hardly say that a doctor who is telling me that optimally I should keep my carbohydrate intake to between 15 to 48 servings of vegetables a day (1/2 cup = 1 serving) is hardly telling me that vegetables and carbohydrates are bad for me. However, while it may be too low for some elements of the general population, that’s a far cry from criticizing someone for taking the tact that what’s good clinically can also be beneficial from a preventative perspective. It’s all about individual physiology and individual needs and health. What is good about the discussions openning up, is that all these knowledge pockets communicate better with each other. My big disappointment with Dr. Perlmutter’s book was that he didn’t address the issue of lectins in many foods, especially grains and legumes, and their role in autoimmune disorders, especially as can impact schizophrenia, bipolarity, multiple sclerosis, and a few others, since he is a neurologist. It’s not simply higher quantities of glucose that can be problematic. More research needs to be done on these.

        • Richard says

          I did not jump off a bridge either but I know I do not care to…
          I like a whole plant-based diet which includes properly prepared whole grains. If grains make you sick stop eating them. I am healthy eating steel-cut oats, quinoa and several other whole grains after I soak and ferment them.

      • says

        You’re right Chris, he does state it that way. I often filter so many blogs and writings, given the importance of fibre in so many ways, that I assume people are talking about digestible carbs when they mention carb limits. But you’re right, that in the spirit of accuracy, these assumptions are my own and not the writer’s.

  9. Zach says

    I think it’s important to remember that we should never be taking an axiomatic approach to dietary advice, whether it’s Perlmutter saying “Carbs are bad,” or Chris saying “Carbs are okay, most of the time.”

    The important thing is that we listen to our bodies. What does your qualitative sense of well-being and quantitative lab results say about your health? This is where the truth lies for us all individually.

    I know for myself personally, I feel that I thrive when I am in moderate ketosis all the time. Does this mean I think carbs are bad? No. Just listen to your body.

    • Daphne says

      I agree…while I try and be very low carb and “Paleo”, I have to allow one day every 10 days or so for grains or else I become extremely sluggish and my digestion slows to a halt. Its finding that balance on an individual basis that is the “sweet spot”

    • JP says

      I agree, Zach. I have followed a relatively low carb approach for the last several years with carbs well below 60 most days and do very well on that approach. One day or so most weeks, coinciding with high intensity training, I eats lots of white rice or sweet potatoes. Even when I don’t cycle the carbs in, I still feel good and perform consistently mentally and physically. On no occasion do I ever knowingly eat grains or grain-based products. Since making these changes, all of my health markers have improved along with body composition.

      “Carbs” to most people is not sweet potatoes, yams or white rice, but instead things like cookies, crackers, bread, french fries, etc. I think virtually everyone would be better off going low carb to avoid these items than eating these particular types of carbs.

      If one doesn’t have access to a kitchen and groceries, it’s very hard to consume safe, “whole food” carbs. When is the last time you saw a sweet potato, that wasn’t fried in some type of bad oil, on a menu? Even one of the relatively plain white rices at my local Whole Foods has sugar as one of the ingredients.

      I read the book and that it was excellent overall.

  10. Sarah says

    I’ve read Grain Brain. My family is affected by Alzheimer’s, and I am seriously afraid of this disease. Grain Brain was pretty powerful to me. I do think the book goes to a difficult extreme, but if his protocol does work, I would gladly do exactly what Dr. Perlmutter instructs. The problem is that I have no idea if it truly works for everyone, and works without other, negative consequences. As with everything regarding nutrition, there seems to be one smart person saying one thing, and another smart person saying another. Trying to make an informed decision about nutrition for me and my family has become nearly impossible. Thank you for your viewpoint on this important issue. I tend to trust your opinion above others, and am thankful for your blog and podcasts.

    • Chris Kresser says

      This is exactly the issue. I know Alzheimer’s is scary, but so far I haven’t seen any evidence that avoiding whole-food carbohydrates will prevent it, or that eating them causes it. Certainly we all agree that avoiding refined flour, sugar, and other processed carbs is preventative. But telling people to severely restrict whole-food carbs in order to prevent neurological disease isn’t supported by the current evidence.

      • Mary says

        So Chris, please clarify, are you saying that none of the supposedly compelling evidence Dr. Perlmutter presents in his book actually suggests, in your opinion, that total glucose load on the body over years and years may contribute to Alzheimer’s and other neurological disorders? Or is it that you have not come across such evidence elsewhere?

        • says

          Mary, I suspect that Chris’s silence on your direct question is because he really has not reviewed the studies that Pearlmutter reviewed, and that Chris is not being forthright when he negatively says “there is no compelling evidence”. I see Chris as muddying the waters on this one, rather than offering clarity. I think his concern may be to reach out to his fan base to be seen to be saying “something, anything” rather than be silent on this significant book. All direct and forthright comments requesting clarity have been ignored by Chris, and it seems that the comments full of unqualified compliments for Chris are the ones that get comment from him. That’s very disappointing.

          • BrittDoc says

            Actually, Kurt, I think Chris probably just doesn’t have time to respond to every query posted here. All of these people buying into the hype of ONE doctor’s opinion when there are hundreds of studies and thousands of years of nutrition proving the opposite is what I find disappointing. Chris isn’t an alarmist who is trying to start a trend, as he most likely knows the simple fact about food that has always been true- whole, non-refined food is what everyone should be eating, and fruits and veggies are necessary for good health. Accusing him of not researching is just childish.

            • says

              Brittdoc – you are so right on target! I can’t imagine devoting all my time to answer accusatory comments rather than actual discussion.

    • Martine says

      My family is also affected by Alzheimer. I’ll admit that I haven’t yet read the book, but I did listen to a whole bunch of his interviews. It seems to me that the key here is how controlled is your blood sugar. If you have perfect blood sugars, maybe eating carbs isn’t such an issue. But if your blood sugar level is all over the place and your H1BC is high, there is indication that the carbs you are eating are damaging you.

  11. says

    Chris – I’d like to add #4 – Decreasing carbohydrates to <60g per day in turn can decrease available fermentable substrates for the gut flora. Which can lead too gut dysbiosis and other harmful changes in gut flora resulting problems in the brain.

    Many foods that are "higher" in carbohydrate foods are also "higher" in fermentable substrate that is beneficial for the gut flora. I'm not saying that a VLC diet has to be lacking in this area but that it is a struggle to obtain that same amount of substrate that a person would naturally eat on a non-carbohydrate restricted diet and therefore many people will fall short in this area.

    New research is coming out each month on the link between a healthy gut flora and a healthy brain.
    Here's a couple good summaries of where things are at:

    • Chris Kresser says

      I mentioned this at the end of point #3 “Long-term VLC diets can also lead to imbalances in gut bacteria due to a lack of prebiotic fiber, which can result in digestive issues.”

      But I agree, it’s important enough that it should have been its own point.

      • Johnson says

        Chris, what do you think about the emerging connection between immunity and microbiome? Those at Free the Animal seem to be reversing their constipation and cold body temperature which started with their VLC diet through resistant starch supplementation. I’m not sure if this actually raises FT3/T3, but that seems quite conceivable given this new link. Also, your FBG seems to improve due to resistant starch. But seriously, the most startling connection seems to be between gut flora and autoimmune diseases like RA. For example, this just came out last week:

        “It’s been suspected for years and years, both in humans and in the animal model, that the development of autoimmune diseases like arthritis is dependent on the gut microbiota,” says immunologist Diane Mathis of Harvard Medical School in Boston. Now, she says, those suspicions are beginning to be confirmed in humans. “It’s a very striking finding.”

        Is it possible that VLC/ketogenic diets could lead to autoimmunity by leading to an imbalance and the resurgence of the wrong kind? One can’t help but wonder because of the significant leukopenic effect I see in these low carbers (most are ok at 4s but some fall into the 2′s immediately upon cutting carbs).

      • says

        Can’t one be in ketosis but still get plenty of fiber by choosing where you get your carbs, I.e. Vegetables? 10 Brussels sprouts have 15 grams of carbs and 5 grams of fiber. 2 cups of cooked cabbage gives you 28 grams of carbs and 10 fiber. One cup of carrots gives 12 grams of carbs and 4 grams of fiber. This would give you more fiber than the average America but you would probably remain In Ketosis.

        • Mary says

          Yes, you can. I sometimes go under 50 grams of carbs for periods of time, and my fiber intake definitely increases as a result. For me, when I am not restricting carbs, all of those high-fiber, low-carb vegetables are not appealing, but when you restrict carbs under 50 all of a sudden you start really enjoying brussel sprouts, broccoli, etc.

          • JULIE says

            Mary! Totally agree!!!!! It’s amazing how DELICIOUS a plate of cabbage “noodles” and a huge green salad becomes when I have dropped grains. Greens not grains. :)

      • Kurt says

        Chris, creating the illusion that somehow Dr. Perlmutter is against vegetables with his recommendations really is doing his work a disservice. I agree with you that prebiotic fiber is essential for our health and specifically our brain and immune health because our gut flora convert these to short chain fatty acids. Since Dr. Perlmutter’s recommendations encompass eating from 10 up to 50 servings, and beyond, daily of fibrous vegetables, I would have liked to have seen a more responsible disclaimer by you before you wrote this important section on #3. You create the illusion that Dr. Perlmutter’s recommendation will lead to fiber deficiencies. To the contrary. And to suggest otherwise, Chris, is professionally irresponsible.

        • Mary says

          Having read the book and been very impressed by it, I have to say I agree with Kurt. And, forgive me for being so blunt Chris, but your having given such short shrift to something as compelling as Grain Brain does not exactly recommend your upcoming book as an essential addition to anyone’s library…

          • BrittDoc says

            Mary and Kurt, just think for a second about the explosion of alarmist diets that have emerged from behind every rock in the past twenty years. Do you notice a pattern?? The diet we have ALWAYS known to be healthiest, which includes fruit and whole grains, always prevails, and the fad falls by the wayside. Every. Single. Time. To believe in something that is just another one of those theory diets when we have thousands of years of tried and true nutrition is just a little silly. People are constantly trying to vilify foods that have already been proven essential to a healthy diet time and time again. Perhaps they want to blame good wholesome foods so they can pretend that what has truly caused our spike in diabetes, obesity and heart disease is from processed, refined sugar and other junk isn’t being consumed by anyone. Kurt, you keep insulting Chris didn’t read the book- I did. I’m a physician as well. It’s baseless and not a solid theory. Sorry. My opinion won’t change.

          • BrittDoc says

            Mary, first of all, I’m a woman. Second of all, I’ve read THOUSANDS of articles, but put no stock in any of them if they’re not backed up with scientific proof in the form of legitimate medical studies. And third, if you believe everything you read, no matter how outrageous, just because “people with degrees” wrote it, you are going to have to believe millions of unproven, flat-out incorrect and conflicting theories. The person who wrote this article, and I, both have doctorates. Therefore, your argument makes no sense. And I have read the article. Where’s the proof and do you have a biochemistry background? If not, I don’t know how to explain to you it’s faults and I don’t know how you could be so adamant it has none,

      • says

        I agree that there seems to be confusion by many experts between use and interchangeability of “glucose” and “carbohydrate”. Perlmutter made it pretty clear that he was talking about glucose, and not non-digestible fibre. Your point is generally a good concern, Chris, but in raising it, you fail to anchor it trully in anything Perlmutter said. So it’s a bit like bullet shot off into the night – noise and impression but not particularly intended for a target.

  12. Ann says

    Great article Chris! I am reading the book now and all the research supports avoiding excess carbs, spikes in blood sugar, and diet and other lifestyle factors leading to silent, chronic inflammation. There is research to support benefits for all for ketones for the brain but intermittent fasting would accomplish that. So yes, I would say he jumps to a very big and possibly dangerous conclusion and once again, people will follow the advice of an expert and 3 months from now, find they aren’t doing so well. People need to use their common sense and listen to their bodies. I have heard him lecture a year ago and he was right on target talking about omega 3s, gluten, inflammation, benefits of intermittent fasting. He does love to engage in dialog – a wheat farmer wrote him a letter and he published it and his response on his website. So perhaps send him a link to your blog. Would love to hear his response. He does have a degree in Nutrition as well.

  13. David Harley says

    I have the book at home but haven’t read it yet. However, I’m a big fan if the low carb diet. It is against conventional wisdom though and while I agree with your point that everyone should find what works for them however I do believe that a blanket LCHF diet would generally leave the average person heslthier than a blanket LFHC diet

    • Chris Kresser says

      I’d agree that the average carbohydrate intake of 300–400 grams per day in the U.S. is too high for most people, especially when they are sedentary.

  14. Dan says

    Chris, how many of these cultures eat such high carbs year round? Do they take a break from carbs during the year to clean the AGEs out of their system? I’ve wondered if a difference between traditional cultures and ours has to do with us having access to carbs year round. Thanks.

    • Chris Kresser says

      There is some seasonal variation, but the Kitavans and Tukisenta live in a fairly tropical environment where the availability of carbohydrates would be year-round.

      • says

        Dr. Seneff has mentioned a few times in her talk today at the Weston Price conference that cholesterol sulfate is required to deal with the AGEs caused by high blood sugar. Cholesterol sulfate is produced by sun exposure. I wonder if tropical people are protected from AGE damage due to their year round sun exposure? Just a thought.

    • Philomina Gwanfogbe says

      I come from Cameroon, more specifically from a tribe whose staple is carb (corn/maize, root tubers) all year round. We grow corn twice a year. I also know one or two tribes whose staple is very closed to ours mainly corn/maize all year round. At least as far as I know there are not many neurological issues among individuals.

  15. Sara says

    Don’t you think that Vitamin D status affects your ability to consume carbs? It would make sense that those living in the tropics could live on high carb diets, whilst those of us further north or south would only eat them in the summer – which would have been when they were available to us. I bet none of the high carb populations were from the far North for example.

    • says

      According to Dr Price’s work, the isolated Swiss lived mainly on a diet of rye bread with pastured butter and raw cow’s milk. I’m not sure of the macro nutrient ratios, but I am certain that the amount of carbs in the milk and bread would put them far out of the VLC range.

  16. Cameron Ross says

    Hi Chris

    I read the book and have been self-experimenting with a keto diet for almost 3 months now. I feel good…not drastically different. The one thing I was surprised to find was that I could go for a 50 mile bike ride with virtually no carbs in my diet and only macadamia nuts and water during exercise. No bonking.

    My diet is relatively high in good fats, not too high in protein and then I have a big green salad once a day, and may supplement with a few raspberries, some daikon, poblano, and always some sauerkraut/kimchi. I’ve been testing my ketones using a blood meter. I’ve been surprised to find low ketone readings…usually no higher than 0.5 mmol/L. My body comp. has improved slightly. I’m 6’4″, 190# and approximately 11% body fat. Since going keto my home scale says I’m down 2 lbs and -2% BF.

    I also read The Art and Science of Low Carbohydrate Performance (Phinney/Volek) for a perspective on fueling exercise while low carb. Their recommendation was a long-term carb consumption of something higher than Dr. P – ~100g-120g/day.

    Just some points from an n=1 experiment.


  17. Jake Ivey says

    I haven’t read the book, but it would seem eliminating grains, which could even be processed or GMO, is a whole different thing than eliminating carbs from whole foods, such as fruit.

    • says

      I’m so confused. I’ve soaked my already fogged out brain (low thyroid, taking levothyroxine) over this past week in a plethora of diet/disease info available on the net.

      I think, but not sure just yet, that Chris’s views on this site make the best sense. I just made out my shopping list based on Dr. Cordain’s (sp?) version of Paleo. Now it seems I need to start over again!!! Help! I’ve missed the past 4 weeks of work so please suggest low budget advice to help me get started. Time’s a-wasting!


      • geneoptimize says


        >> fogged out brain (low thyroid, taking levothyroxine)
        You might want to ask for Armour thyroid (or another brand of NDT natural dessicated thyroid) if you’re having brain fog with Levothyroxine. Or at the very least, ask your dr to check your free-T3 level, then maybe start a little Cytomel (T3) along with the Levothyroxine (T4). Many of us can’t convert the T4 to T3 easily.

        I’ve taken various thyroid meds for about 18 years, and think NDT helps me to have a clearer brain. has good thyroid info and explains more.

        Good luck! I hope the brain fog evaporates soon.


        • Piano gal says

          Just an aside: My husband suffered from brain fog and other thyroid issues, and his MD was unable to regulate his thyroid until his thyroid medication was compounded by a local compounding pharmacy. The reason: he was sensitive to or allergic to whatever they use as fillers in his thyroid medication. And he did try Armour thyroid, Cytomel, and Levothyroxine among other commercial thyroid products. Hope this helps.

  18. Tom Dolan says

    To each his own. But I’ve followed Dr. Perlmutter’s recommendations and feel / function 100% better. Due to worsening hypoglycemia, I’ve been on a low-carb, no sugar, no caffeine, no alcohol diet since the 1970s, and that helped a lot. However, since reading Dr. Perlmutter’s book and further restricting my diet by eliminating, as much as possible, gluten, dairy products, etc. I’ve gotten my old life back. Haven’t felt this good since 1969. Sometimes you just need to go with what works. .

    • Chris Kresser says


      I’m happy to hear a very-low carb diet has helped you. But of course that doesn’t mean it will help everyone, or that it’s even required to avoid Alzheimer’s and other neurological conditions.

      It’s also important to consider where people are coming from when they switch to a diet like this. If you were eating a standard American diet, and then switch to a low-carb, grain-free, caffeine-free, alcohol-free diet, how do you know what provided the benefit? Could you have received the same benefit by simply eliminating grains, dairy, legumes, caffeine and alcohol and not going low-carb?

      This is similar to stories I hear from people who’ve recently switched to a vegetarian diet and feel much better than when they were on a standard American diet. Of course! They’ve eliminated processed and refined crap and are now eating whole foods. The question is how will they feel after a few months or years on the vegetarian approach.

      • Tom Dolan says

        I say my diet is “low carb” but do enjoy abundant carbs in the form of salad greens, avocados, onions, tomatoes, broccoli, cauliflower and other low glycemic veggies. I know a particular food isn’t right for me if it causes sleep disturbance or otherwise makes me feel yucky. I seem to have a compass in my gut that points me in the right direction.

      • Cynthia says


        You need to re-read Tom’s comment. He already was on a low-carb diet, but only recently elimated guten and dairy products and said that he felt better after doing that. It doesn’t sound like he’s been on a standard American diet since the 70s.

      • Janknitz says

        Chris, you very correctly point out that Tom’s post is just one person’s positive experience with a low carb diet which may not be extrapolated to the general population, but I don’t see you making the same argument when others report problems like increased TSH or hair falling out because they went low carb. These are samples of one and there’s no information about possible confounding factors.

        I’m entering my third year of low carb. I still have all my hair. And my TSH did go high at one point, but when I tracked my nutrients around that time I saw that because of hunger suppression I was consuming well under 1000 calories a day. No big surprise that my thyroid was trying to down-regulate the metabolism to avoid starvation. When I increased my calories while still staying under 30 grams net carbs/day, my TSH went right back to normal ranges. It had to do with calories, not carbs.

    • Katherine says

      Hey Ginny, you’re off to a good start! Add some white rice and white potatoes to each meal and you’ll be off to the races. Chris is a big fan of Paul Jaminet’s Perfect health diet which includes 100-150 grams carbs from starches per day and doesn’t count carbs from veggies.

      • says

        It is as foolish to recommend a blanket amount of certain carbs to people as it is to recommend a blanket restriction…..
        This is a complicated question and there is considerable genetic and individual variation. Sure, read the views of experts, but in the end, you have to try stuff, see how it affects your body and tweak until you stay feeling good. It is important to recognise your limits.

        I could not balance my blood sugar, make my brain work well and be free of sugar craving and actually stay on a paleo diet without slipping until I cut out all sugary fruits and starches for several months and worked on my gut health a LOT. Now I can eat some small amounts of rice or sweet potato here and there and feel good afterwards and still maintain my nutritive instincts, but still not loads of it every meal. Green stringy veggies I eat in copious amounts however.

        My indigenous ancestors lived for centuries mostly on fish, turtle, seasonal berries and highly treated acorns. Possibly relevant to think about your family history, no?

        I know a lot of people thrive eating the way Jaminet recommends, but it is too much carbohydrate for for my physiology.

        But if you have been eating low carb for more than a month and feel tired and crave potatoes, by all means try eating some.

        Chris is of course absolutely correct that there is no evidence of tubers or rice giving people Alzheimer’s…

        • BrittDoc says

          Alison, your post is completely correct in my view. Far too many blanket statements out there. I say, eat whole foods, but eat the whole foods you tolerate well, while making sure to get adequate amounts of essential micronutrients. I think that’s about as specific as I’d feel comfortable stating to a large group (which would make me a terrible addition to the government’s MyPlate committee).

  19. sharon says

    i think alzheimers is in the top 5 causes of death in the us. so not everyone is going to get it from eating a high carb diet. but the ones who will get it are really looking at the cause to figure out prevention. i think a high carb diet is a likely cause.

    • Chris Kresser says

      Again, there’s no evidence that its carbohydrates, per se. That’s the point of this article. If you have evidence that actually supports this idea, I’d love to see it.

      • Kurt says

        Chis, Dr. Perlmutter affirms that he wrote his book in response to 252 professional, peer reviewed studies that were published in well regarded scientific journals, which substantiate his thesis. Yet you say those same studies don’t exist. You just state that, as you did here, without any other qualifying comments. Why don’t you get in touch with Dr. Perlmutter, find out which studies he’s incorporated, and then write a followup article that substantiates your as yet unsubstantiated accusation? I and many others would love to see what you come up with.

        • Mary says

          Or maybe Chris could read the book and then point out which supporting evidence he feels that Dr. Perlmutter is misrepresenting.

          I’m rereading parts of the book now, and Dr. Perlmutter focuses on insulin resistance resulting in high levels of circulating insulin and high blood sugars as what actually damages the brain. If we could ask him the question, I bet he would say if someone knew based on testing that they were highly insulin sensitive and therefore had excellent control of blood sugars despite eating Paleo carbs, then they could perhaps eat more without raising their risk of neurodegeneration.

          I think his recommendation of below 60 grams of carbs is meant as a general recommendation, assuming that not everyone follows their insulin level regularly (I can’t even get that test from my doctor).

          One thing that I haven’t seen mentioned yet on this thread is Dr. Perlmutter’s point that the brain may be experiencing inflammation and undergoing damage without one being aware of it at all. There are no pain sensors in the brain, which means that we do not feel inflammation in the brain. So for all the people that are just “listening to their body”, they might want to get their fasting insulin tested to be certain that they are not insulin resistant.

          Or yeah, I guess they could just take Chris’s word for it that there is no evidence that Paleo carbs cause any problem whatsoever, and gorge on sweet potatoes as long as they feel good doing it!

          • Debbie says

            Actually, perhaps we all should know what our glucose levels are before and after meals, and adjust carbs accordingly. I believe Chris has said that, and Dr. Perlmutter would probably agree. I’m not sure there is such an enormous gulf between them.

  20. says

    Thanks for a great and important article Chris. There has been so much buzz around Grain Brain. In my opinion the book suffers from information bias. Therefore I´m very grateful for your rational approach on the issue. I know both you and I have nothing against Paleo or carbohydrate restriction in general. However, there is no doubt that “Grain Brain” deserves a rebuttal and yours is fair and based on scientific knowledge. Here is mine:

  21. says

    I’m so confused. I’ve soaked my already fogged out brain (low thyroid, taking levothyroxine) over this past week in a plethora of diet/disease info available on the net.

    I think, but not sure just yet, that Chris’s views on this site make the best sense. I just made out my shopping list based on Dr. Cordain’s (sp?) version of Paleo. Now it seems I need to start over again!!! Help! I’ve missed the past 4 weeks of work so please suggest low budget advice to help me get started. Time’s a-wasting!


    • Peg N says


      I’d buy Chris’s book when it comes out, and follow his suggestions. Meantime, for low budget, how about eating a small amount of rice or yams/sweet potatoes with every meal? Say a stingy handful. Eat all the red, orange, yellow and green veggies you want. Eat a couple of fruits per day, preferably one of which is berries. Eat about 3-4 ounces of meat per meal. Learn how to make a bone broth and have a soup made from that plus some veggies daily. Avoid grains, beans and sugar and trans fats.

      Good luck!

      • Ginny says

        Thank you Peg! I wish Chris’s book was already out. I’m having symptoms that I suspect might be ALS and I’m terrified. But that can be a good thing since I was such a resolute sugar/carboholic before. Now I am willing to do whatever it takes to minimize/slow or halt the progression of these symptoms, whatever they are. I see the neurologist on Tuesday.

        • Joanna says

          Hi Ginny,

          In addition to seeing the neurologist, you should follow the recommendations you find here. So far my personal experience with neurologists (the best in the field) hasn’t been very promising. You may be on your own anyway. You may find yourself tested, diagnosed and then having your symptoms “managed” without any attempt at finding the root cause. You might also try a good functional medicine doc to complement the neurologist. My understanding is that they really are focused on the whole picture and making people better rather than just managed. Good luck to you!

        • Mary says

          Ginny, in my opinion, if you have symptoms that seem anything like ALS you should (beside visiting your doctor, obviously) try the Perfect Health Diet, and in the meantime, buy Dr. Perlmutter’s book and read it.

          He is an MD with specialties in both Neurology and Nutrition, and talks specifically about neurodegenerative diseases, including ALS, which he deals with on a daily basis. He also talks about the tests that you can do to make sure that poor blood sugar control is not contributing to your problems.

          Also, you mention that you were a carboholic. I have this tendency, and I had no success with the Perfect Health Diet simply because it could not keep my carbs to a moderate level. I’ve tried many times to eat “moderate” carbs as the Jaminets recommend, but I eventually end up bingeing on high carb foods. So I’ve finally recognized that for me it’s either very low carb (ketogenic) or high carb. Since I have signs of insulin resistance (abdominal fat) and signs of neurological decline, the very low carb diet is clearly the best choice for me (I never crave carbs when I am doing very low carb).

          Certainly give the PHD a try and if you can keep carbs moderate and you are convinced that you are sufficiently insulin sensitive to handle the carbs (and after reading the book Grain Brain you agree with Chris that there is no evidence that Paleo carbs contribute to neurodegeneration), then great!

  22. Desiree Parham says

    If you’ve read the book you would’ve gleaned the following.

    He is not recommending that we keep fruit and other whole carbohydrates out of the diet, in fact he discusses that whole food is better due to the pectin and the fiber that it contains. However, he recommends keeping the intake lower due to the research that’s come out on the brain and dementia. A high fat, lower carb diet will decrease your risk of a neurodegenerative disease by 40% and a high carb diet will increase risk by 3.6x (Mayo clinic study).

    Perhaps there are areas of the world where they eat higher carb diets, but I live in the United States. Also, Alzheimer’s runs in my family. I’ve been adapting his protocol for a couple of weeks and have been feeling great. Also, I’ve had problems with overeating sugar in the past (even whole carbohydrate) and this is improving since adopting his recommendation for lower carb.

    I do think that each individual will need to tailor this protocol to themselves. For instance if you’re an athlete you’re going to need more carbs.

    As far as evolution, here’s a quote: “Evolutionarily, sugar was available to our ancestors as fruit for only a few months a year (at harvest time), or as honey, which was guarded by bees. But in recent years, sugar has been added to nearly all processed foods, limiting consumer choice. Nature made sugar hard to get, man made it easy.” Dr. Robert Lustig et al

    • Chris Kresser says

      I didn’t say that he’s recommending avoiding fruit or whole-food carbohydrates. I said he’s suggesting that carbohydrate intake (from all sources) be limited to 60 grams/day. If I have misinterpreted this recommendation, I’d like to know. Otherwise, my argument stands: there’s no evidence suggesting that eating more than 60 grams of carbs a day in the form of fruit and starchy plants like sweet potatoes and plantains contributes to neurological disease.

      • Desiree Parham says

        Here is from his website:

        On the Grain Brain diet I recommend no more than 60grams of carbs/day. However, for extreme athletes, 90-100grams is permissible.

          • Heather says

            You have not misinterpreted this recommendation.

            He spends an entire book talking about specific carbs and then gives a recommendation of a number of carbs. He could have said: “don’t eat grains, don’t eat added sugars, don’t eat industrially processed foods. Fructose is bad unless it’s from whole fruit. Veggies are okay. But don’t eat more than 60g grams of them a day. I have Reactive Hypoglycemia and I can eat more than 60g of carbs a day AS LONG AS THEY COME FROM PROPER SOURCES. I can even eat 60g in one sitting AS LONG AS THEY COME FROM PROPER SOURCES.

            He’s kind of sending a mixed message. If carb source is so important then why only 60g? What if I work out a lot. What if I have a really physcial job? My man wouldn’t be able to do his physical job on 60g of carbs a day.

            Here are a couple of excerpts from Grain Brain (I happen to have had my Kindle eCloud open on my PC – on Grain Brain – when I decided to check your site):

            “…While fructose alone may not have an immediate effect, it has more long-term effects when it’s consumed in sufficient quantities from unnatural sources. And the science is well-documented: Consuming fructose is associated with impaired glucose tolerance, insulin resistance, high blood fats, and hypertension. And because it does not trigger the production of insulin and leptin, two key hormones in regulating our metabolism, diets high in fructose lead to obesity and its metabolic repercussions. (I will clarify later what this means for those who enjoy eating lots of fruit. Fortunately, for the most part, you can have your fruit and eat it, too. The quantity of fructose in most whole fruit pales in comparison to the levels of fructose in processed foods.)… “

            “…When we eat whole fruits, which obviously contain fruit sugar, the water and fiber will also ‘dilute’ the blood sugar effect. If you take for instance, a peach and a baked potato of equal weight, the potato will have a much bigger effect on blood sugar than the watery fibrous peach. That’s not to say the peach, or any other fruit for that matter, won’t cause problems. (4)
            Our caveman ancestors did in fact eat fruit, but not every day of the year. We haven’t yet evolved to be able to handle the copious amounts of fructose we consume today – especially when we get our fructose from manufactured sources. Natural fruit has relatively little sugar, when compared to, say, a can of regular soda, which has a massive amount…”

        • Mary says

          The question above was in response to Chris’ assertion: “there’s no evidence suggesting that eating more than 60 grams of carbs a day in the form of fruit and starchy plants like sweet potatoes and plantains contributes to neurological disease.”

          Dr. Perlmutter makes a very clear argument, that appears to be well supported by research, that in a person with any degree of insulin resistance, upwards of 60 grams of carbs from starchy plants could indeed be contributing to neurological degeneration long before any “disease” was diagnosed.

          Chris, rather than nuancing your critique, you seem to be just hard-headedly stating “No evidence that Paleo carbs can contribute to neurological issues” with no further discussion. I don’t think that’s very responsible of you.

  23. park chi says

    I been following the work of ray peat and my health has never been better! My diet consist largely of dairy, gelatin,rice, potatoes, small amount of meat, coconut sugar, fruits (dates and orange juice make up a large percent) I average well over 300g of carbs a day in the form of mostly sugar but yet my health continues to improve (as noted via blood test results)

    • Janknitz says

      And here’s where Chris should say: “I’m very glad this approach helps you. But of course that doesn’t mean it will help everyone, or that it’s even required to avoid Alzheimer’s and other neurological conditions.”

      But he didn’t.

  24. Jose says

    Of course it is the carbohydrates.The excess sugars glycate the LDLs that carry cholesterol and fats to the brain, blocking the synapses of the neurons.I don’t know what kind of evidence is needed,is right before our eyes.I could revert the argument:how many doing low carbs or in ketosis get Alzheimer’s?

    • BrittDoc says

      Jose, where is this evidence? There are NO proven links from carbs to Alzheimer’s. Also, to say carbs cause neurological disease is ridiculous. We’ve been consuming high carbs for centuries, and other countries still do and yet Alzheimer’s wasn’t an issue until fairly recently, and not for those other countries. Now highly refined and processed carbs? Maybe. Carbs from whole foods? Almost certainly not. Your statement is way too broad. To say a whole group of macronutrients cause a brain disease caused by prion activity is very far from being factual or based on actual proof.

  25. Fabi says

    I read his book and it was incredibly helpful. I even started following a very low carb but then realized I was restricting too much. I now am eating more fruits, tubers, sweet potatoes. I think you make a good point explaining that this diet is not necessarily good as a preventative measure. I think you audience is different from his intended audience. Most of your audience is aware of the dangers of processed fruits, especially grains and sugars. He is writing for the general population and does a great job explaining how harmful processed foods are. He also does a great job explaining the cholesterol myth and how dangerous it it’s to have low levels of cholesterol. He is also very informative when he speaks about statins and supplementation a and blood work he suggests. Overall his book is fantastic, but each person needs to use his judgment to decide what is best for him. I think the greatest battle here is to have people rethink all their intake of processed foods, especially grains and sugar, and to stop thinking that taking statins will magically undo all the harm of a crappy diet. Thanks for the post!

  26. Rosemary says

    As some one with generalized dystonia ( a neurological movement disorder, attributed to genetic predisposition and a head trauma) and working on my Master’s in Nutrition, I eagerly awaited and read Dr P’s book. I was disappointed in some ways but glad to have read it in others. For example, there is not a iota of evidence to suggest VLC helps dystonia, yet he suggests it several times in his book. That said, I follow a whole foods, low carb, gluten free and dairy free diet, albeit with no benefit. To me Dr P’s biggest and most important message was avoiding and/or managing high blood sugars. I regretted that his book had such a “pop” nutrition aspect to it but maybe that is needed to sell books these days. I too- as suggested above- think it suffered from “information bias”

  27. Susan says

    Thank you for the common sense perspective. I am reading Grain Brain and have read numerous
    paleo and low carb books over the last few months. I got to the point where I was
    afraid to eat a small organic apple! Too many carbs! I am presently not really eating
    low carb, but I do think I need to reduce my carbs a little, especially the gluten free bread.
    I love a couple of servings of fresh fruit every day and enjoy sweet potatoes and occasional
    rice or quinoa dish. I appreciate the balance this article brings.

  28. says

    Thank you Chris for writing this post. It is also in line with what Robb Wolf was saying about Grain Brain, and a post on his site a couple weeks back. Basically, just because a VLC diet is (at least temporarily) therapeutic for metabolically broken individuals (whether it’s in the brain or otherwise), is not a sufficient reason to extrapolate that to the generally healthy (paleo/ancestral) population.

    However, having read the book, I am fully on board with how he has debunked, if you will, a number of conventional wisdom theories. Specificall, that saturated fat is bad and cholesterol is bad. I am also glad that not only did he say the above were not bad for us, he actually provides valid arguments that they are, in fact, absolutely required to maintain our bodies homeostasis. Not to mention the added ammunition this book brings to the war on gluten. I also think the way he has presented this information is straight forward enough for the general public who have limited knowledge in this area and care not for the science. I know all of us in this discussion are well aware of the above facts, but a book like this that is getting a solid level of publicity is just one step in the right direction on the sat fat, cholesterol, and gluten front. Hopefully it will simply lead people to begin their own search for nutrition knowledge, and ultimately end up on this site :-)

    As always Chris, your insights on topics like this never disappoint, keep up the great work.

    • Chris Kresser says

      Hey Andy,

      I’m sure Dr. Perlmutter and I agree on far more than we disagree on. Thanks for your feedback and sharing you experience.

    • says

      Andy, I think you might be referring to the post I wrote for Robb Wolf’s site. Here’s the link, in case anyone wants to check it out:

      I have to say, I wrote my graduate thesis on Alzheimer’s as “type 3 diabetes,” so I’m pretty firmly in the camp that supports low-carb diets for neurological health (and a multitude of other conditions), but I understand and agree with the notion that just because it’s therapeutic for severely damaged people doesn’t automatically mean it’s required for everyone else across the board. More detailed thoughts are in the guest post.

      • Mary says

        Wow, this guest post on Robb’s site is excellent. Very thoughtful and nuanced view on the limitations of Perlmutter’s recommendations with reference to individual differences in the ability to regulate glucose adequately based on a variety of different factors. Highly recommended for anyone who is worried about the implications of Perlmutter’s recommendations or who wants to know about the different factors that affect carb tolerance.

  29. Cathy says

    I have read the Grain Brain, and to be honest it did scare me as my father died this year from Lewy Body Disease, and my grandmother and great-aunt both died from Alzheimers. However your article gives me hope, because whilst I have tried very low carb for several months in order to improve my health, (and this has certainly helped stabilise my blood sugars), I didn’t feel that I could maintain this long term because I didn’t have enough energy. I have been reintroducing fruit to my diet quite successfully along with small amounts of starchy vegetables and rice. So thank you for your balanced opinion which reinforces what I’ve been feeling.

    • Mary says

      So sorry to be blunt, but I think this is a really good example of the danger of such a simplistic critique of Dr. Perlmutter’s recommendations. You have severe neurogenerative disease in your family and a problem with blood sugar control, yet you feel OK adding in plenty of starches because Chris says Paleo carbs are good to go? I really hope you will reread Perlmutter’s book, look at the guest post on Robb’s site and get tested to make sure you are insulin sensitive before you add in lots of Paleo carbs because it’s easier than low carb. There are ways to tweak low carb to increase energy for people that need to remain low carb to prevent neurodegeneration. Of course, you could also wait until you are diagnosed with Alzheimer’s before doing anything, which seems to be what Chris is suggesting–your call!

  30. Michael says

    Hi Chris,

    Thanks for posting this article.

    I’m interested if you can comment on the transition from a VLC diet to a more regular carb intake. As you have pointed out in this article and many times before the VLC can be a great tool for therapeutic purposes.

    For myself I have had great success with a VLC diet in getting my weight under control. How is it that one can transition back to a higher intake? And, in the case of someone using a VLC to combat Alzheimers would they ever get to a point where it would make sense to reintroduce more whole food carbs.

  31. raphi711 says

    Chris, do you think this is a smart approach: reduce your carb intake as much as possible whether you are an athlete or a desk-slave, as long as you don’t notice any obvious and negative effects discernible directly from your level of dietary carbohydrate intake….of course, do this while continuing to vary your diet (eschewing the large majority of grains, legumes and all non-raw dairy)?

  32. Ian says

    I have neurological and mood disorders that can get severe, and restricting carbs has helped a lot. I’m doing the Paleo Autoimmune Protocol and am starting to have some days where I’ve felt better than ever and I’m 33. So your take on this seems more reasonable to me because it is individual.

    Sweet potatoes/yams, winter squash, carob, and coconut work for me, but if I eat fruit… even lower glycemic stuff like berries/apples/pears I want to eat the whole bush/tree and I always find myself wanting to go off on a binder after I have the first piece. I don’t have this so much with the sweet potatoes/winter squash/carob/coconut, but I still have to watch how much I eat of those… especially with the carob/coconut.

  33. Michael says


    I do plan on getting your book in december, but I am just starting to do a Paleo derived nutrition. I have had digestive issues for over a year and after speaking with my Gastroentologist, he is recommending trying Paleo, he did recommend Ron Wolf’s book in particular cutting out grains/gluten. Digestion is slow, bloating, and so on. But all tests show negative thru colonscopy/upper endoscopy/cat scan/ultrasound, but they did remove gallbladder earlier this summer. Do you have any recommendations in how I should approach it or a book you might recommend?

    Keep in mind, I am very active exercise five days a week, worry about if cutting my carbs too much, will get weak and hurt my workouts and weight loss, what is an acceptable number in terms of carbs per day for someone active?

    • Peg N says


      I’ll second Michael. A series on care and feeding of a person, post gall bladder surgery, would be wonderful! (in your spare time.)

  34. Marusia Marrapese says

    There is a Lysosomal Storage Disorder called Fabry’s disease that our geneticists say only occurs in 1 out of 40 to 60 thousand newborns. They are born either with too little or none at all of the enzyme alpha-galactosidase. This leads to lysosome storage of glucose and glcolipids in the lysosome of the vascular endothelial lining ior smooth muscle. Taiwan in 2009 screened over 177,000 consecutive births and found it in 1 out of 1,250 newborns. This is a very big example of why low-carb, low-fat with “Beano” support can save lives. We do not screen for this in the US. Are you aware of this inherited disorder Chris?

  35. Cathryn says

    So glad you wrote this, Chris. I’m often amazed at the popularity of books that take somewhat extreme viewpoints, but then, I suppose this appeals to many perhaps because it seems to simplify matters. Like so many others, I did VLC for a couple of years and then did not feel well so added in rice and sweet potatoes, cyclically, and many things improved, not the least of which was severe dry eye. I average 100-125 carbs a day and it seems to work very well for me. I very much appreciate your well-thought out approach to diet and health and tend to favor it over a dogmatic approach.

  36. Julia says

    I read Grain Brain because I was hoping it would be a good book to give my 75 y/o mother for Christmas. Her own mother had Alzheimer’s and she’s beginning to show minor signs of cognitive decline. IMO, her diet relies too heavily on fruit juice, pasta and whole wheat bread, and I’d love to see her switch to whole fruits, starchy veggies and more healthy fats, eliminating gluten entirely. She doesn’t listen much to what I tell her about diet so I’m looking for a source of information that she’ll respect. I thought Dr. Perlmutter did a great job indicting gluten as harmful to brain health. However, because of his frequent recommendation to dramatically reduce carbs, I decided this isn’t the book for my Mom. Maybe “Your Personal Paleo Code” will be the right book to convince her to get off gluten. What d’ya think, Chris?

    • Mary says

      Wow, someone who has Alzheimer’s in the family, high carb consumption and signs of cognitive decline and a compelling, research-based book by a practicing neurologist is not the right book because his recommendation goes contrary to what one would prefer to eat. Honestly, your mother is the one possibly facing imminent Alzheimer’s. Give her the book written by the neurologist and the Personal Paleo Code, and let her decide which is more compelling and how far she is willing to cut carbs, if at all, to reduce her risk of Alzheimer’s.

  37. Lynn says

    As one who could not seem to control herself in between meals, but was continually snacking, this diet has helped break an addiction cycle. I can go four to five hours in between meals now and for me, this is a great thing. This is my one month anniversary since starting the diet; I’ve come down 15 lbs., and my blood sugars are now consistently in the 90s, sometimes the 80s for mg/dL, whereas before they were in the pre-diabetic to diabetic range. For helping me to stop that continual grazing, to pointing me to information about supplements that are of epigenetic interest, I cannot thank him enough.

    I think if we consider not only neurological conditions, but the possible forerunners or conditions which exacerbate neurological diseases — namely, the increasing obesity and prevalence of type ii diabetes in our culture, what Dr. Perlmutter proposed in his book has great potential. Diabetes is a key issue here, and it’s on the rise. There’s no question if you drastically reduce carbohydrates, eat good fats and proteins, exercise aerobically, drink lots of water, and try to sleep well, that your risk for diabetes plummets – and with that, a whole host of issues, such as heart disease, kidney disease, peripheral neuropathy – AND the effects Dr. Perlmutter says diabetes has on the brain. Since there is an epidemic of diabetes and obesity in our culture, and assuming there is a connection between these conditions and the neurological diseases of the brain, the brain grain diet has a much wider application to our modern culture than I perceive you are stating.

    I do agree with you about the importance of eating whole grains with fiber.

    I think the question for me is – do the inflammatory and free radical issues brought on by type ii diabetes contribute to neurological disease? The answer appears to be that they do, and this diet is an antidote for that. Diabetes and obesity must be considered here, and the main cause of diabetes and obesity is over consumption of carbohydrates. Dr. Perlmutter’s diet has a big population in this country that it could help.

  38. Alex says

    My take is that carbs are just a source of energy. The problem I see is that we do not walk 10 miles per day or climb up a tree to get those sources… we take a car and go to the supermarket.
    Also, carbs are addictive. That is a good thing and probably is driven by evolution: in the past it pushed our ancestors to walk those 10 miles and climb that tree to get them. Today we have easy access to abnormal quantities of refined sugars, and all we have to do is to sit at a desk 8 hours per day to earn the money to buy them later.

    Personally, I found my balance. The days I don’t workout (or just do low cardio like walking or hiking) I get most of my calories from fats and try to stay low in carbs. On days of weightlifting or HIIT sessions I enjoy my baked potatoes, some fruits, etc. I guess I eat about 120-150 grams those days (but that’s just a guess, I do not like counting). The insulin spike is not a concern: muscles are severely depleted, the liver possibly is, too. Insulin will drive glucose into them, while promoting protein anabolism by inhibition of muscle protein breakdown.

    “We cannot command nature except by obeying her.” – Francis Bacon (1561 – 1626)

  39. Justin Spencer says

    Ever since listening to Dr. Barry Groves, PhD, Real Food Summit presentation “Homo Carnivorus: What We Are Designed to Eat”, I have looked at the “safe starch” debate with a greater emphasis on gut flora.

    First, let me say that I share the opinion with the likes of yourself, Paul Jaminet, and Stephan Guyenet in this regard.

    In Barry’s presentation he breaks down the energy extraction from 100 g of dry matter in a gorilla’s diet after accounting for fermentation of fibre to SCFA as follows:

    11.8 g PRO, 47 kcals, 20.5%
    7.70 g CHO, 30 kcals, 13.1%
    0.50 g FAT, 4-5 kcals, 1.9%
    SCFA, 148 kcals, 64.5%

    Ever since, I have wondered what percent of SCFA from fermentation constitute the diet of populations such as the Kitavans, Tukisenta, and Okinawans, and how that plays into this whole story. Now, I’m not ignoring the fact that a significant portion of the diet of these populations will directly consist of sugars and starches, but I’m just curious what significance SCFA from fermented fibre plays in distinguishing the differences between refined foods and whole foods. The other notable distinguishing factors being nutrients, minerals, water content, etc.

    Just like amylase expression, gut flora may be another likely reason explaining individual variances in “carbohydrate tolerance”. I hypothesize that those who have flora dysbiosis, hindering their ability to convert significant amounts of fibre to SCFA will not be deriving energy from SCFA that they would be otherwise. Thus, they a lesser satiety signal will be perceived and they will still seek to satisfy their hunger. If they choose to satisfy themselves with more carbohydrates, rather than a fat, to compensate for the SCFA that they did not produce, this could lead to an increased glucose load on the body with increasingly possible adverse affects as that glucose load increases.

    To illustrate this concept more clearly, say we have two age matched, genetically identical subjects; subject A and subject B. Subject A has the gut flora to efficiently ferment fibre, whereas the flora of Subject B completely lacks this ability. Both are metabolically identical with identical energy requirements of 2000 kcal. Both are fed meals consisting of a whole food starchy carbohydrate, say yams, ad libitum. I would expect subject B to eat 500 g of carbohydrate and Subject A would eat an amount less than that, with the balance of calories coming from SCFA, which was fermented form the fibre naturally found in the yam.

    It may seem like I am putting a large emphasis on this aspect of the argument, but in reality I simply want to bring my thoughts to the attention of others here that are like minded, because I haven’t seen this been given much attention.

  40. Onur says

    Number 13 is a type of study I call useless. It gives people an advice to restrict fruits to 2 pieces or less, or an advice to eat at least 2 pieces of fruits a day but there’s nothing to say when it comes to what they eat instead of fruits and instead of what they eat fruits.
    This is enough not to draw conclusions from but this is not good also in the study:
    “Fruit intake was self-reported using 3-day fruit records and dietary recalls.”
    Other than that this is a very good article and since an average person might take the issue of fruits just like that in the study, just to increase or decrease it without any other knowledge, that part may be better than nothing also; but the audience is better than average here already…

  41. David H says

    There was an article in Life Extension mag recently titled “Elevated Glucose Increases Incidence of Breast Cancer and Brain Shrinkage” Which states:

    “A large body of published scientific research documents that people with higher after meal glucose spikes have sharply increased risks for most of the diseases we associate with aging, such as Cancer, Alzheimer’s, kidney failure, retinal damage, and vascular blockages” They cite 13 different studies.

    A low carb diet certainly has helped my health and energy, it just makes so much more sense than to risk damage from higher blood sugar.

  42. Tom Dolan says

    The “Mediterranean diet” with its various grains might not work for some of us because in Europe most grains have less gluten than ours. Also, pastas in Europe are typically made fresh from softer flour, which contains less gluten. If this is true, someone who can’t tolerate the American “Mediterranean diet” might do better with a real Mediterranean diet: Pasta freshly made from grains with less gluten. Or so I’ve read.

  43. Honora says

    Yes, for example I know an Ethiopian who says he has ‘coeliac disease’, yet can tolerate fermented pancakes (injara) made from Indian origin chappati flour (whole wheat) and rice flour but he can’t of course tolerate the other forms of fermented whole wheat available here in New Zealand (prob. NZ or Australian origin).

  44. Joyce says

    Chris, Thanks so much for the information in this post. Because of it, I will neither buy the book (which would no doubt even increase my confusion and anxiety about what I eat even more) or heed his advice. I happened to see Dr. Perlmutter on Dr.Oz while I was waiting for my daughter at the orthodontist. You should have seen the reactions of the people in the room while he was on. He showed a model of a brain with a big chunk of it having been destroyed by “carbs.” People’s mouths were just hanging open in disbelief with lot’s of comment like; “Oh no, I thought X, Y and Z were good for me and now this guy is trying to tell me they aren’t…”

  45. Courtney says

    I think it is very important to add here what protects the brain: healthy fats, exercise, etc. I’d love to see a link at the bottom of this article to your work (and likely agreement with Dr. Perlmutter) on nutrition and brain health! :)

  46. lucy says

    I think it’s so important to do what’s right for you, when it’s right for you. Which is so, so different from an ‘all or nothing diet’.

    I’ve eliminated grain, alcohol and refined oils.

    I’ve cut down on sugar.

    While increasing good fats and mineral/nutrient dense foods like bone broth.

    I eat unlimited veggies, herbs and potatoes. Limited fruit.

    I am refraining from calling it low carb or high fat. It’s rather a series of tweaks that work for ME.

    Cut the processed crap. Eat real food. As Chris advocates, it’s not all or nothing but a series if tweaks! Don’t get caught up in the black and white thinking.

  47. Glupidio says

    Chris, did you actually read Grain Brain in its entirety? There were 250+ citations supporting his statements; did you review them?

  48. Paul Manfre says

    I did read Grain Brain several weeks ago and I am happy that you cleared up the information. I did buy into it and implemented a low carb diet with new found conviction because getting Alzheimer’s for me would be worse than death and if this diet could inoculate me then eating this way was easy. I did have reservations about his theories too. The good news is that after eating this way I finally sleep better, usually through the night. I use to need naps during the day or find myself nodding off at work, this does not happen anymore. I also lost 17 pounds! I am saddened by the fact that this diet will not stop me from getting Alzheimer’s, but I always new in the back of my head it had many flawed theories, I am also happy that I can enjoy some carbs knowing that it will not kill my brain. I am curious how all my levels will look when you check my blood next time. Thanks Chris you are a calming voice in the storm!

    • Joanna says

      Paul wrote, “I am saddened by the fact that this diet will not stop me from getting Alzheimer’s…” This is not the point that Chris has made in his article. He is making the point that there is no evidence that eating particular kinds of whole food “safe” starches will cause Alzheimer’s. That’s not the same thing.

  49. says

    I am a neurologist interrested in functional medicine, particularly as it relates to regaining/optimizing health in the face of neurological conditions. Admittedly, my experience in the area of functional medicine is limited. Thanks, to solid thinkers like Chris Kresser, and others, my knowledge base — and personal philosophy — is growing. Helping individuals improve their health must take into account their own individual journey through life, where they are at the moment in time when they encounter the powerful information conveyed by a paleo/ancestral diet and lifestyle. That said, there is a body of neurological literature which correlates both cognitive decline and brain atrophy with increasing serum glucose/hemoglobin A1c levels, even when these levels would be considered “normal.” So, what do I personally do? I have trained my body to be a better fat burner. I start my day with Dave Asprey-styled coffee and snack on nuts (almonds, Brazil nuts) during the pre-noon hours, if I feel a little hunger. My noon meal is typically a salad with olive oil, sometimes nuts, bacon, often protein. But at this point in the day I am introducing carbohydrates by way of some root vegetables (like beets and carrots), and then the balsamic I use on my salad. Mid-afternoon a snack is a piece of fruit (often a banana). Dinner is usually fish/grassfed beef and vegetable, and occasionally sweet potato (particularly if there has been a work out), and often I’ll have some blueberries for dessert. Generally, I’ve been enjoying a glass of wine in the evenings. So, this is a low carb-ish approach that periodizes carbs for the second have of the day and around the time of work outs. This approach has controlled my appetite, improved my gut health, evened out energy levels, and helped keep me “sharp.”

    • Chris Kresser says

      Hi Ken,

      To be clear, I haven’t argued that increased glucose and A1c levels aren’t correlated with neurological disease. I’ve argued that there’s no evidence that consuming whole-food carbohydrates like starch and fruit contributes to chronically elevated insulin or glucose. That is a key distinction and one that many seem to have glossed over in the article and comments.

      • Mary says

        So, you are admitting that glucose disregulation (increased blood glucose and A1C levels, chronically elevated insulin) is linked to neurological disease, but you are arguing that there is no evidence that whole-food carbs (starch or fruit) can contribute to this?

        So, if a person (diabetic, pre-diabetic or just a cautious “healthy” person) tracks his or her blood glucose with a glucose monitor and notices that whole-food potatoes, rice and fruit affect their blood sugar as much as bread or pasta, then what–their meter is just wrong, and they can ignore it because there is no specific evidence that these whole-food carbs can contribute to neurological degeneration?

      • Danny says

        Chris you just said: “To be clear, I haven’t argued that increased glucose and A1c levels aren’t correlated with neurological disease.”
        Immediately after you said: ” I’ve argued that there’s no evidence that consuming whole-food carbohydrates like starch and fruit contributes to chronically elevated insulin or glucose.”

        Ive worked as a pathologist for 9 years and do a lot of glucose, insulin, lepton tests. The way we test for insulin RESISTANCE is 3 tests over a 4 hour period. testing on an empty stomach. Then eating 40g of carbs from eating measured green apple WHOLE. Waiting 1 hour and testing again and then another hour and then another hour.
        The way it works is if you’re producing insulin but its not working properly (insulin resistance), your body produces more insulin to take care of the carbs you eat. (literally ALL forms of carbohydrates turn into blood sugar (glucose) so after each hour if you’re resistant then there will be an increase and its clear then if your insulin is working correctly.

        Youd be surprised at the results. After thousands of tests I’ve found that there has been increased levels of insulin from ingesting whole fruits.

        You used the term chronic, well if people are eating the same foods daily then you could call regular carbohydrate intake chronic elevation of insulin in the blood.

  50. Jamie says

    I myself have suffered from severe depression for years (it’s my go to illness) and I have had a significant head trauma after bashing my head and fracturing my skull with bleeding on the brain.

    I have tried ketogenic diets to help alleviate some of the symptoms after hearing some of the beneficial effects it can have for people with neurological conditions such as mine. And I fully believe that ketogenic diets can be an extremely powerful diet for people with neurological conditions such as depression and brain injury.

    However, for me, it absolutely wrecks my health. My sleep tanks, I feel even more depressed and anxious, my cognitive ability goes downhill and my physical performance drops. I did it for several months and I actually lost 8lbs in muscle. I was only doing powerlifting at very low reps.

    So I myself now eat very low carb in the morning and afternoon (less than 30 grams of carbs) and then for my evening meal most days I’ll have between 100 to 150 grams of carbs. I must add I eat copious amounts of coconut products for its ketogenic inducing properties and I do love all things coconut. Alas, after doing this I now sleep well, feel good about myself and can function properly. It’s all paleo of course as grains and dairy (again, individual with dairy) are what makes me feel like real crap.

    • Jamie says

      I’m just going to modify what I said previously. When I wrote the original comment I had only just started adding carbs back in and initially I found some success with it. However I found that just adding carbs back in the evening didn’t help me enough so now I eat plenty of carbs throughout the whole day. I’m talking 200 grams plus with plenty of coconut products of course.

      I just sometimes forget to eat food as I never get hungry cos I eat plenty of coconut and paleo foods.

      I can honestly from my n=1 experiment that carbs are not the devil incarnate and very low carb shouldn’t be the defacto way to go.

      Anyway, it seems to be working a lot better for me.

  51. Brett says

    Great article and great follow up discussion. Such an active post! When was “grain brain” released? It seems a little like you’re jealous of all the attention he’s getting and so had to nit pick some of the minor details rather then commending him for a job well done. Then you go on to plug your own upcoming book! This is certainly a good way to piggy back off someone else’s success since your article probably comes up when someone types “grain brain” into their search engine. Regarding the merits of the research: I think the author of “grain bran” went out on a limb to make a guideline of 60g of carbohydrates a day. The danger in doing this is a lot of people obsess over meeting exact numbers. Others, like me, add it to a pile of knowledge from different experts and try to set up rough guidelines for eating. We keep in mind that our bodies are capable of reaching homeostasis in a lot of different dietary conditions and that it’s those fluctuations that create resiliency. So, maybe restricting to somewhere around 60g per day over a lifetime is a good loose rule. Maybe that number can increase during the sun exposure months when the fruit is ripe and our vitamin D and cholesterol sulphate levels are high and it lowers in the winter months when animals are fat for hibernation and they are our only source of food. So how about everyone keep in mind, including the author of the “grain brain”, that fluctuations are not only okay but probably exactly what the body needs. Not a continual source of HFCS nor a complete elimination of carbs.

  52. Mary says

    I am new to your website and I am also knew to lots of incredible information you put on your website. I am trying to change my diet to improve many symptoms I have from autoimmune diseases so I am trying to educate myself. I have been advised to remove all grains, dairy, legumes, nightshades, sugars but I really have hard time because by removing all grains and white potatoes I don’t eat enough carbs and I feel worse than before. I really don’t do well on a low-carb diet and I don’t need to be on it, I just don’t know how to get my carbs without eating pasta, rice, or white potatoes. Do you have an article on what food provide the best source of safe carbs? tHANK YOU

    • PC says

      Hi Mary, I would recommend looking into The Perfect Health Diet by Paul Jaminet or buying his book. He recommends eating carbs from safe starches like rice and sweet potatoes as well as getting plenty of good fats. This plus supplements and probiotics supposedly helps autoimmune problems.

    • Jamie says

      Hi Mary. I wrote his earlier and the effects of very low carb sound similar to mine. In terms of eating the right kind of carbs then I do well on white rice, white and potato and over ripe banana’s. I seem to do well on high glycemic paleo carbs which give me a quick hit all at once rather than eating carbs throughout the day. Experiment yourself on this and also try roots and tubers that fall under the paleo diet. Here is what I wrote.

      “I myself have suffered from severe depression for years (it’s my go to illness) and I have had a significant head trauma after bashing my head and fracturing my skull with bleeding on the brain.

      I have tried ketogenic diets to help alleviate some of the symptoms after hearing some of the beneficial effects it can have for people with neurological conditions such as mine. And I fully believe that ketogenic diets can be an extremely powerful diet for people with neurological conditions such as depression and brain injury.

      However, for me, it absolutely wrecks my health. My sleep tanks, I feel even more depressed and anxious, my cognitive ability goes downhill and my physical performance drops. I did it for several months and I actually lost 8lbs in muscle. I was only doing powerlifting at very low reps.

      So I myself now eat very low carb in the morning and afternoon (less than 30 grams of carbs) and then for my evening meal most days I’ll have between 100 to 150 grams of carbs. I must add I eat copious amounts of coconut products for its ketogenic inducing properties and I do love all things coconut. Alas, after doing this I now sleep well, feel good about myself and can function properly. It’s all paleo of course as grains and dairy (again, individual with dairy) are what makes me feel like real crap.”

      • Mary says

        I actually have the same problem with low carbs but the problem for me is that the autoimmune paleo doesn’t allow white rice or white potatoes. So I don’t know what to eat to get a good carb intake. I hope Chris will answer this for me.

        • Mary says

          Sweet potatoes, winter squash, rhutabega and turnip I think are OK on autoimmune, carrots, onions are also relatively high in carb so a nice leek soup is good. Fruit is OK on autoimmune, I think, so that is also a very good source for people that don’t want to do low carb. Robb Wolf has a lot of free stuff on his website which could be useful to you, plus a good forum. Mark’s Daily Apple is also a great forum.

  53. IveyLeaguer says

    Hello Everyone,

    I’m hearing a lot about white rice in this thread as a safe carb. I’ve avoided it because I’ve always assumed it was processed and most of the nutrients removed during “enrichment”. I’ve gone for brown rice instead but rarely eat it because it doesn’t feel right somehow.

    Can anyone clear this up? Is brown rice superior to white rice?


    • says

      Ivey — if I understand things correctly, the reason white rice is considered a “safe starch” is because the problematic proteins and other substances that make brown rice difficult to digest are removed during the “polishing” that makes white rice. White rice does lose some nutrients compared to brown, but in brown rice, some of those nutrients are bound up to phytic acid, which makes them less bioavailable anyway, unless the rice is soaked/sprouted.

  54. David says

    In central and western Asia there are wild fruit trees, some with fruit the same size as in modern orchards. Full-size apples, for instance. I am sceptical of “killer apples” unless one’s body has been so badly damaged that one has developed type 2 diabetes.

    If fructose turns out to be more of a problem than glucose, there are other fruits which are a bit lower in fructose than apples and still very sweet; e.g., apricots.

    Even where I live in England it is possible to eat home-grown fruit from May/June through to March/A

  55. pwvegas says

    Personally, I am grateful that this philosophy is finally making it into mainstream media. (in spite of corporate sponsors….Dr Oz!!). And yes it is the extreme side of low carb, which is what I feel MOST of the average American population needs to reverse the effects of the SAD. You are preaching to the choir so your audience who may not need to take it to this level but I know for a fact that this is having impact on those who have ignored it all together in the past (my family). This is a new beginning. Now if we can get Oprah on board it will be a shoe in….

    • Mary says

      Actually, it’s not the extreme end of low carb. Ketogenic diets (Jimmy Moore style) are what I would call the extreme end of low carb. There are a couple of excellent lectures about these diets on Youtube by Peter Attia and Jeff Volek. I think some people would say that Perlmutter’s recommendation of 60 grams of carbs may be harder to maintain than a keto diet or a moderate carb diet, because it’s low enough to restrict the energy available from carbs but not low enough to produce substantial amounts of ketones.

  56. says

    Hey Chris,

    I’m a fan & grateful for all I’ve learned from you. You may have a partial point here, but I’m getting the feeling that you might have missed the bigger picture on this one. Your repeated requests for research to back Dr. Perlmutter’s recommendations lead me to think you might not have read the book…and are basing your opinion on a knee-jerk reaction.

    I get that limiting carbs for everyone seems restrictive. Easy for me, as I’m at high-risk of a neurodegenerative disorder, being homozygous APOE ϵ4. Research illustrates that ϵ4 carriers (in a dose dependent fashion) do demonstrate glucose uptake/metabolism dysfunction years before symptoms appear. A mildly keto-adapted diet provides my brain with an alternative (preferential) fuel. This application is ground-breaking for high-risk patients like me. To date, the medical establishment has no treatment, nor agreed upon prevention measures for Alzheimer patients. To have healthy dietary parameters spelled out is nothing short of a lifeline for many of us with risky genes or a strong family history.

    Is it excessive to recommend this way of eating for everyone? More and more research is demonstrating that elevated blood glucose levels (even within normal ranges) DO lead to an increased risk of dementia.

    Glucose Levels and Risk of Dementia

    Can whole foods cause or contribute to elevated blood glucose levels? Sure, many fruits, corn, potatoes, etc. are metabolized very similarly to highly processed foods and most definitely can elevate blood glucose. I keep my carbs between 60-70 grams, basically unlimited above-ground vegetables and a few small servings of fruit a day- hardly VLC- loads of healthful whole foods.

    I would respectfully recommend that you take the time to read the book- if you haven’t. It’s based on real science, is quite do-able (I’m 8 months in), and may offer a plan to prevent a plethora of brain disorders, heart disease, obesity, cancer, and more.


    • Trundle says

      You’re looking at one sided research. You can design any research to implicate high BG with neurodegenerative diseases. Does anyone doubt that hyperglycemia, everything else being equal, could lead to conditions like Alzheimer’s. The problem here is that even an isolated neorological condition like Alzheimer’s is multifactorial. It’s not controlled entirely by the ApoE4 genotype; nor is it by hyperglycemia. There are other factors involved and a huckster like Perlmutter looked at research designed for the neurologically impaired and how their symptoms ameliorated after shor-term ketogenic diets.

      Your problem with such a diet is that a ketogenic diet will straighten out your BG, give you stellar lipid numbers, and may prove palliative for neurological symptoms, if you have any. But it will lead to immune and hormonal dysfunction. The effect is stealthy and latent, so you’ll never be able to tell via symptoms. “Well, I feel great!” Of course, you feel great. It’s like asking a heavyweigth boxer like Ali while he was beating up everyone. Hey, Muhammad, do you think 20 years fro now, you could be feeling the effects of Parkinson’s?

      A ketogenic diet results in immune deficiency by kickstarting autoimmune pathogenesis and/or immune deficiency. This usually starts out by slashing your WBCs by 25-50%. They will keep falling for some people. That absence of gas you because you no longer ferment starches and fiber will lead to dysbiosis where microbes that play important immune function will be eviscerated. That’s why most ketogenic dieters go onto develop autoimmune disease 5-10 years down the road; it’s not just the low T3, high cortisol, and low T, which are hormonal issues. I’ve seen some of you guys develop a serious condition like Common Variable Immunodeficinecy, which is considered idiopathic by modern medicine and takes 10-15 years to diagnose. If you’ve been in long-term ketosis, get your immunoglobulins and igg subclasses checked. Chances are, that after 2-3 years, at least one will be deficient. This is a long-term health disaster you’re courting by believing a huckster like Perlmutter. He hopped on the bandwagon to expand his South Florida practice; but he’s a clinican who hasn’t done sufficient due diligence.

      • PC says

        Hi Trundle, can you add some links to back up what you say? I would like to do some of my own research on this – a lot of people say ketosis can cause immune problems or disrupt gut bacteria, such as Paul Jaminet, but I’m not sure where the evidence is coming from?
        For example how do you know that ketosis slashes WBC count? As someone with already low WBCs and who is doing a keto diet and has a friend who is doing it too, I really need some answers.

        • Trundle says

          PC, listen to your body and look at your own blood labs. Compare WBC counts before and after your diet. I’ve seen hundreds. Go over to Dr. Kruse’s forum where people post blood labs. Their WBCS fall by 25-75%. For some, this is normal and healthy; if your WBC is in the 7s, that’s inflammatory. But I’ve seen some who fall into the 3s and 2s. That’s automatically lymphocytopenic or neutropenic or both. The cause for that has to do with at least 4 factors that get kickstarted when you go ketogenic: (1) triglyceridemia — high serum FFA and very low triglycerides are a breeding ground for autoimmunity; (2) mucin deficiency in the digestive tract, especially in the small intestine, which parallels secretory IgA deficiency — this is caused by glucose deficiency that Jaminet talks about — all lead to the worsening of intestinal permeability and autoimmune pathogenesis; (3) T lymphocyte dysfunction due to low leptin and thymus atrophy — this could show up as low WBCs and low lymphs but not always — you need igg and immunoglobulin subclasses to check this; and (4) gut dysbiosis which is intimately linked to immunity This is breaking news: your microbiome imbalance is beling linked to autoimmune diseases T1 diabetes, RA, etc. (Go over to Dr. BG and check her blog on the human microbiome.)

          You see how gas disappears when you low carb? Some low-carbers are overjoyed that they no longer fart. You can’t fart because there is no fermentable starches and that leads to an imbalance of the microbiome where beneficial bacteria like Bacteroides are overtaken by predatory, pathogenic bacteria like Prevotella copri. (See the RA article). Your gut microbes play an indispensable immune function; ketosis and VLC dieting decimate many of the essential bacteria; that’s what a no-starch diet does to you. That shows up as long-term immune deficiency or autoimmune diseases, if you’re genetically susceptible. But who’s not susceptible these days? That explains why so many people develop food allergies upon going Paleo: these are all low carbers who’ve compromised their immunity. Worse, it takes 5-10 years to correctly diagnose autoimmunity or immune deficiency. You’ll never know since it’s asymptomatic. But it’s progressive and degenerative and once it gets kickstarted, it cannot be reversed. Among Dr. Bernstein’s diabetic patients, autoimmunity is 100%, hypothyroidism is 90%, Raynaud’s is 80%, serious immune deficiency like CVID is 33%. That’s coming from the good doctor’s mouth; I’m not making this stuff up. He himself takes immnoglobulin injections every 3 weeks to fight off infections; many of his patients do after being in ketosis for 10+ years. Many of these guys go on to develop lymphoma. He’s been claiming that such disease are comorbidities of diabetes but he knows what we’re dealing with. Long-term ketosis and VLCing will lead to a train wreck. Just because you feel great doesn’t mean you’re healthy.

          You seem like a bright guy, PC. Go look up those citations, google other terms, and make up your own mind about Perlmutter and his ilk. What they’re promoting is based on shallow science, short-term trials, and inadequate examinations of hormonal and immune dysregulation. There is a plethora of current literature that’s linking gut dysbiosis, which is almost automatic when VLCing, with autoimmune diseases. To say it’s disturbing is an understatement.

      • Mary says

        Julie, I suggest that you have a look at the lectures on ketogenic diets by Peter Attia and Jeff Volek (search Youtube). There is also a really good (though technical) series on keto-adaptation on Peter Attia’s blog the Eating Academy.

        I am on a ketogenic diet and I am not without concerns. I have tried a moderate carb diet but cannot seem to maintain it (any appreciable amount of carbs causes me to crave high-carb foods so much that I eventually lose all control ;-) so for now I am choosing a ketogenic diet, partially due to Perlutter’s arguments in conjunction with the fact that I have signs of insulin resistance and cognitive decline.

        Jeff Volek and Steve Phinney are the experts on keto diets–they do lots of ongoing research, have two books out and lectures on Youtube as I mentioned. Before letting the comments from Trundle scare you off your diet, check out these sources so you can make a considered decision given your genetic susceptibility to Alzheimer’s.

        • Trundle says

          Mary, do you know anything about the condition Julie suffers from? Do you even know how to spell it? Let me spot you the first 3 letters: CVI. The reason why a ketogenic diet is ill-advised for someone with Julie’s problems is that it she already has severely compromised immune defenses. She should be under the care of a qualified hematologist but she is instead following a rogue neurologist who’s regarded “out there” even by those in the profession. Even Dr. Lustig doesn’t agree with him. Do some research on this rogue neurologist who’ll “promise you the moon and stars” in the argot of his colleague and fellow neurologist, and blame everything on one thing, carbs.

          It’s a simple and seductive message, easy to digest. Being healthy and avoiding dementia is really simple if you only cut the carbs. These are one-trick ponies who’ve been at it for years. You, as much as you do not understand the research of Volek, Phinney, Perlmutter and other opportunists with a single villain theory, are an unfortunate victim to his publicity stunt. You do not understand what Volek and Phinney are talking about, right? You are not very cerebral and have to get it down to soundbytes: Insulin is gonna drive me mad. Hyperglycemia is gonna hit me with Parkinson’s. Free radicals are gonna inflict Alzheimer’s on me!

          I’d say you need to develop a bit more analytical skills before offering advice to someone with a serious and life-long condition such as Julie. It’s not your own health; it’s someone else’s. .

          • Bruce Wilson says

            “Do you even know how to spell it? Let me spot you the first 3 letters: CVI.” Why don’t you humor us and spell it out yourself? Otherwise you come across as a pompous ass.

            So do you have any actual scientific credentials, or are you self-educated internet know-it-all that likes to respond to posts four months after they have been posted?

  57. says

    I don’t remember what it’s called, but my friend Brad has a disorder. If he eats bread he develops a learning disability. It’s like the bread puts a roadblock in his brain. When he doesn’t eat bread, he’s really smart and alert.

  58. Tom Bihn says

    I recently had blood work done and have a TSH of 13. This would indicate I have an issue with low T3 or T4, but if I don’t have symptoms, I wonder how concerned I need to be. I eat a relatively low carb diet, but definitely not VLC. Based on this logic, should I eat more fruit to raise my carb intake and possibly correct the TSH levels?

  59. says

    Hi Chris,

    Excellent response! I not yet read this book, but it’s certainly on my list. My impression from listening to Dr. Perlmutter on the various podcasts he’s been on was that he wasn’t necessarily advocating the elimination of all carbs. Perhaps he hasn’t clarified, or perhaps he has and I missed it. I interpreted his stance as similar to everyone else in the Paleosphere’s, that highly processed and manufactured carbs should be eliminated and that fruits and veggies from whole-food sources were perfectly acceptable.

    I agree with you that the recommendation to keep intake to <60g/day is highly restrictive and the only obvious way to do that is to also restrict intake of whole-food carb sources as well. Which, as you point out, seems excessive and lacks supporting anthropological evidence.

    As Tyler said, we need to find out what works for us and go with that. And I too, would be interested in Dr. Perlmutter's response to your thoughts. Any chance of getting him on your podcast? He's been on all the others! :)

    Thanks again for all the great work you do, I've learned a ton from you! Keep it up!

  60. Wenchypoo says

    Question: did anyone take AGE into account here? When people of both genders turn 50, the blood-brain barrier tightens to the point that glucose cannot get through to the brain, because the hormones that use to wrap around glucose molecules are no longer present–all the glucose ingested (directly or as digested carbs) merely goes to raising your BG levels, because the biggest consumer of the glucose (your brain) has been lost.

    At that point, all these neurological conditions becoming common nowadays (re: Alzheimer’s) are really THE BRAIN STARVING and pruning dendrites to save the central core. Get fat-adapted all you want, but it may not be enough in the end. We simply DO NOT produce enough ketones for the brain to run on them alone!

    So how do we stop this brain-starvation in spite of the pesky blood-brain barrier thing? We take L-glutamine on an empty stomach–why an empty stomach? That’s the only way it passes through the barrier sans hormones. Take this stuff with a meal, and all it does is get into your blood, raise your BG, and possibly feed your muscles.

  61. ChocoTaco369 says

    There is a huge disconnect in the paleo community that irks me to no end, and some of these comments help reinforce it. Remember in the 70′s and 80′s when all fat was demonized? The paleo community seems to recognize that all fats are NOT created equal – fats from fresh beef, fish, eggs and nuts DOES NOT EQUAL fats from refined seed oils, margarines and hydrogenated biscuit dough. However, the paleo community as a whole cannot seem to understand that potatoes and fruit DOES NOT EQUAL high fructose corn syrup, saccharine and aspartame. The average paleo enthusiast will blame the addictive properties of cookies, ice cream, brownies, Cheetos and Doritos on the “carbs” but all of these ‘foods’ are as high if not higher in fats than carbs. Check the labels.

    There are many comments here that seem to automatically discount fruits and starches with the argument that “our ancestors didn’t have fruits and starches available all year round and modern fruits/starches have been engineered to have more sugar and less fiber.” Human beings evolved at the Equator, which means we DID have access to fruits and starches all year round, and the meat that tends to populate that area tends to be lean and gamey. The few hunter-gatherer and traditional cultures left tend to eat far more carbs than fats because of this, yet they are free of modern disease. You can bet our ancestors would’ve rather gone out and leisurely picked fruit than painstakingly chased after potentially dangerous animals for hours on a hunt. We’ve probably been eating fruit longer than anything else on Earth, and while modern fruit may not be the same as ancient fruit, neither is modern meat. Cows, chickens and pigs are engineered hybrid animals bred over generations to have different flavors, fat compositions and tolerances to the environments they are raised in. Modern meat is no less engineered than modern fruits and starches, so if you let “perfect” be the enemy of good, you will starve to death.

    Fruit is awesome, and sugar is incredibly healthy provided the source is of high quality. Refined sugars are nutritionally equal to refined fats, and honey, maple syrup and molasses all run circles around fats like coconut oil, olive oil and tallow in terms of nutrient density per calorie. Instead of arguing over fats and carbs, just eat real foods and focus on nutrient density per calorie while minimizing anti-nutrients. It is a massive disconnect that it is acceptable to drink coffee with half a stick of butter emulsified in it but a packet of white sugar in your coffee is blasphemy. Empty calories are empty calories, and eating butter is no different nutritionally than eating sugar. Trace Vitamin A you say? There are more trace minerals in dark brown sugar than grassfed butter due to the molasses content, so relax and eat real food, not tubs of coconut oil.

    • Onur says

      Did you know that butter is the richest source of butyric acid after ghee, which is clarified butter ? And benefits of it ? No.
      Did you know that macronutrients may be isocaloric but not isometabolic ? And which macronutrients had the difference ? No.
      You might have been eager to find the truth about things you said but apparently, you couldn’t yet. Some people, like Chris Kresser, may know much more than you seem to think they do. Try to talk less about an issue when there are people that know much more than you about it and are supposed to explain, and are already explaining it…
      Someone may leave a better reply.

  62. Ryan says

    Great post! It seems like the LCHF/Paleo crew is becoming almost cult like against carbs. Especially with ketosis being the big craze these days. I have to admit I was more towards that boat until I came across you, Paul Jaminet, and Dave Asprey. Now I use a combination of all your diets and feel a lot better than I did on a very LC diet… Thanks so much for all your insight!!!

    • Trundle says

      I don’t know how you came across Asprey, but he’s one of the low-carb hucksters who believe in the metabolic advantage nonsense. He’s in ketosis and believes that allows him to eat more and not gain fat. Perlmutter here hopped on the low-carb bandwagon without doing proper due diligence on the dangers of ketosis and VLCing. What I see is a bunch of ardent low carbers all getting excited because of their weight loss and BG numbers. Then after 2-3 years, they all develope side effects and all drop off and move onto higher-carb Paleo. But there are some hardcore ones who stick to ketosis due to morbid obesity, t2 diabetes, neurological problems, etc. These guys who go onto do long-term ketosis for that long will develope serious autoimmune diseases, immuen deficiency, hormonal dysfunction, and gut dysbiosis. I’ve seen these guys develope serious conditions like lupus and scleroderma; these are lifelong conditions they must contend with.

  63. Billy says

    All that needs to be recognize is that (before the wonderful world we live in today) we wouldn’t be eating the same way year round, and that there would be periods of fasting and over eating- high carbohydrate and low carbohydrate. Would save everyone a lot of headache…

  64. Paul Riemann says

    It seems to me that the issue at hand concerning fruit and simple starches is one’s personal carbohydrate tolerance. Both Chris and Dr. Perlmutter agree on the subject of gluten, and grains–like corn and soy. If one’s HbA1C, fasting blood glucose, and post meal blood sugars are in a healthy range when consuming fruit and starches, then why would it matter how much they consume?

    On the other hand, if you’re obese, insulin resistant, and/or diabetic, then you will probably do best limiting fruit and starches…at least until you are able to correct the metabolic derangement. I once was rather dogmatic about LC. But it’s difficult to argue with the data on populations that consume carbohydrate rich diets and not only survive, but thrive. What these populations don’t eat is refined sugar and processed foods, and that is likely the reason they are able to avoid the degenerative diseases that those on the Standard American Diet are suffering from in increasing numbers.

    As Chris said, there is no compelling evidence that consuming fruit and starches will cause neurological disorders. And I would add, as long as one’s postprandial blood sugars are in a healthy range (under 140 mg/dl) after eating fruit and starches then there is no need to be too restrictive.
    I have found Chris to be rather unbiased, reasonable, and not too dogmatic. He follows the science and takes rational stances based on a preponderance of the evidence. I think he’s spot on here.

  65. Joakim says

    Where have you got this miss information that the older generation of okinawans eat a high carbohydrate diet…THEY DO NOT!

    Their diet is high fat, moderate protein and low carb.

    Get your facts right!

    • Janknitz says

      I agree with Joakim. I grew up on Okinawa and I laugh at all the assertions that the Okinawan diet is 85% carbs. You can cite all the studies you want to claim that, but anyone who has sat at an Okinawan’s table can tell you it’s not true. It’s and island–they eat lots of fish, seafood, sea vegetables. They eat pork and cook in its fat. They eat eggs, chicken, and beef. During famine, they even ate the poisonous habu snakes on the island. They eat a lot of veggies, especially Goya–bitter melon, and fermented pickles and sauces. They drink astringent green tea. Yes, they eat rice and noodles, too. But not 85% carbs.

      I think there are many factors that went into their healthy traditional diet, but to claim it’s starch-based just isn’t true.

  66. Sofia says

    These sort of trends scare me, because they often get interpreted in the extreme.

    1. Not all dietary carbs cause high blood sugar. People need to first understand glycemic index and where their favorite carbs fall in the categories. Second, some carbs are also relatively high in fiber, which slows glucose uptake in the intestines, preventing spikes in blood sugar (i.e. berries). In general, avoid high glycemic foods!

    2. Once you’ve got glycemic index down, understand that wheat is not what it used to be. The wheat we consume today, even organic wheat, is a hybrid of wheat from the days of old. Wheat has lost many of its critical nutrients. I cut-out bread, cereal and wheat products from my diet and I felt great! No more bowel issues. Less inflammation. And I’m not even gluten intolerant.

    3. The brain absolutely positively requires glucose as it’s energy source to function. No other will do. Not fats! Not protein!

    • Mary says

      #3 is just wrong. The brain can also burn ketones, which are derived from fat. Please see the lectures by Jeff Volek and Peter Attia before you start throwing misinformation like this around.

  67. says

    I hate to jump in the fray…but feel compelled after reading Trundle’s comments. YOU, Sir, have my attention and rather perfectly describe my condition (hypogammaglobulinemia/CVID, gut dysbiosis, and leukopenia) PRIOR to beginning Dr. Perlmutter’s protocol. I’ve been on the diet he prescribed for me for a year now and ALL of those conditions (and more: mast cell activation, severe reynaud’s, reactive hypoglycemia,etc.) have virtually disappeared. My IgG is now in a normal range after years of being around 400-500. My white cells are in the 4′s- up from 2.3.

    I consulted him after learning of of my APOE4/4 status, which predisposes me to a high risk of developing Alzheimer’s. He prescribed a Paleo-ish Diet for me, fat:65%, protein:20%, carbs:15%. My carbs are around 60-70 grams a day- all whole food. My plate is primarily organic, seasonal veggies, high Omega-3 proteins, and healthy fats. I SEE that Dr. Perlmutter seems to have gone slightly lower carb in his new book, but I haven’t. I’m mildly ketoadapted at best, but cognitively sharper than I’ve ever been, healthier and stronger than I thought possible. (FWIW, I wasn’t eating a SAD before, but rather a typical “healthy” American Diet, lowish fat/lowish carb- some refined carbs.)

    I found Dr. Perlmutter after seeing an impressive lecture he did at NYU, entitled “Alzheimer’s Can be Prevented.” It blew me away. I read some of his old books, checked out his resume- have you? Wildly impressive, former Linus Pauling award winner, etc. I don’t think he’s jumping on anyone else’s bandwagon…but rather bringing life saving, life-EXTENDING advice to a nation poised to implode from an Alzheimer’s epidemic.

    Maybe, Trundle, all of those things you predict will return for me. I hope not…. Alzheimer’s is currently considered incurable. The pathology occurs years before symptoms show up. If you wait until they do, it’s too late. I have a predicted risk of 50-100% based upon which research I read and when you take my other risky genes into account.. Dr. Perlmutter’s message is nothing short of earth-shattering to my population and for anyone concerned about cognitive health. I wouldn’t be so quick to dismiss, my friend.

    • Mary says

      Way to go Julie. I commend you, not just for your fabulous health reversal, but for your extremely well-stated (and respectfully stated) support for Dr. Perlmutter and his contribution.

  68. Tom B says

    I appreciate Kessler’s thoughtful response to the book.

    Keep in mind the thing that Perlmutter is most concerned about is gluten — which is pretty much avoided if one follows a Paleo approach.

    To the extent there are aboriginal people who live on carbohydrates and are healthy, I’m fairly certain they aren’t living on modern hybrid wheat, corn and soybeans — they’re living on tubers and fruit.

    I don’t think fruit should get a free pass though. Some supermarket fruit is essentially candy that would never have existed in nature — such as Thompson grapes, Cavendish bananas, navel oranges. We know the sugar in fruit is chemically identical to high fructose corn syrup — why would you want to put that in your body repeatedly. Why not think of fruit as a candy or dessert — enjoy occasionally, in moderation, but if you’re eating it constantly you are probably addicted to the sugar.

    Truth is, there is a great deal in common between LCHF and Paleo — both are on the right track and both approaches should produce considerable health benefits over a conventional diet based on cereal grains. Whether you eat fruit or a lot of sweet potatoes may not matter greatly as long as you are getting sufficient fat and protein.

    As Kessler notes, the beauty of the debate over diet is that everyone is free to run their own experiments and see what works in their case. The biggest problem with changing diet is what people are capable of sustaining over the long term. So if you need bananas in your life, then you work around that. If you need pasta, or bread, or oatmeal, perhaps you try to restrict it to one day a week to minimize the inflammatory and blood-sugar effects.

  69. Tom B says

    Trundle sounds very authoritative, but note his citations are not actually supporting his arguments. The theory that LCHF or Paleo could wreck your immune system or hormone balance in 3 years or 10 years is interesting, and alarming if true, but the data for it is just no data to back this up and without knowing more about Trundle I’m not inclined to take his word for it.

    Old paradigms die hard. We know in the days of Robert Atkins, many in the medical profession spread old wives tales trying to scare people away from low-carb eating (such as intentionally confusing ketosis with ketoacidosis) — but as the research has been done, the old wives tales fell by the wayside and Atkins — to a lot of people’s surprise — has been scientifically vindicated. (And for what it’s worth the Atkins regimen is controlled carb, but not any kind of strict Keto diet)

    There is obviously not much literature on long term effects of a ketogenic diet, but what has been done has shown almost entirely positive outcomes. And we also know of aboriginal populations (the Masai, the Inuit) who lived on a diet of nearly 100% fat and meat (blubber, in the case of the inuit) and were long-lived and disease free before carbohydrates were imported into their societies.


    A great source for people who want to know more, much more scientifically detailed than Perlmutter, is Gary Taubes, who has written “Good Carbs, Bad Carbs” and “Why We Get Fat.” Taubes is a journalist, not a practitioner or an advocate and is very balanced and fair in his approach — but has concluded the evidence overwhelmingly supports a low-carb diet.

    • Duck Dodgers says


      The Masai have always consumed large quantities of raw milk and honey. Honey is extremely important to the Masai. In fact, this — as well as their weekly habit of trading their meats for sweet potatoes and bananas with neighboring tribes — was well documented even in 1895.

      Secondly, the published scientific literature on the Inuit shows that they were obtaining sufficient carbohydrates from the glycogen in the raw meat they consumed (Heinbecker, 1928, Ho 1972),

      Heinbecker wrote: “…Average daily food partition is about 280 gm. of protein, 135 gm. of fat, and 54 gm. of carbohydrate of which the bulk is derived from the glycogen of the meat eaten.”

      Ho (1972) wrote: “Carbohydrate accounted for only 15% to 20% of their calories, largely in the form of glycogen.”

      Yiu H. Hui, Ph. D. (1985) wrote: “Eskimos actually consume more carbohydrates than most nutritionists have assumed. Because Eskimos frequently eat their meat raw and frozen, they take in more glycogen than a person purchasing meat with a lower glycogen content in a grocery store. The Eskimo practice of preserving a whole seal or bird carcass under an intact whole skin with a thick layer of blubber also permits some proteins to ferment into carbohydrates.” (Principles and issues in nutrition: Yiu H. Hui, Ph. D., p.91 (1985))

      The Inuit ate 8 to 10 pounds of raw meat per day (Sinclair 1953), and raw meat has relatively small amounts of glycogen (animal starch) in it. Diving marine mammals have significant glycogen stores to assist them on their extended dives. And even if their meat only contained the conservatively low levels of glycogen found in Western beef, at 8-10 pounds of meat per day, they were consuming 48 to 60 grams of glycogen per day. Of course they also loved the glycogen-rich muktuk and livers too. High levels of glycogen in muktuk were discovered as far back as 1912 (JAMA: Volume 57, 1912).

      Interestingly, Heinbecker (1928) showed that the Inuit exhibited normal glucose tolerance when fed their traditional diet. But, when Stefansson and Anderson did their year of Western-style meats, Tolstoi (1929) found that they failed their glucose tolerance tests. This suggests that Stefansson and Anderson were unable to replicate the Inuit diet at Bellevue.

      I should also point out that the Masai also preferred their meat raw and fresh. They even drank blood raw and fresh from the leg of their cattle. My guess is that most Western VLCers do not eat this way.

      As the literature shows us, both the Masai and the Inuit consumed sufficient levels of carbohydrate and the Western VLC diet is nothing like what these cultures were doing.

      Every indigenous culture made an effort to consume sufficient carbs. Chronic ketogenic diets are a modern invention, which may be beneficial to those who need it, but haven’t been tested by any indigenous populations.

  70. Maegan says

    I recently found your website searching for a light in all of the darkness of blood sugar issues. I have not been able to leave the site! I have been reading tons of articles, and I am addicted. Thanks so much for providing sound, logical information that always seems to be missing when visiting the doctor.

  71. Mira says

    I have been vegetarian/vegan for 7 yrs and also had a few serious head traumas in life so far, and now appear with degenerating brain and nervous system damage, along with other systemic damage related to endocrine, immune, digestive, etc. Have seen lots of doctors, specialists, practitioners, etc and no improvement. They say there is nothing to do that hasn’t been tried and things will only get worse. According to Paleo or “Grain Brain” concepts, I would have to eat meat right?

    For ref, I did the “elimination/anti-inflammatory diet” thing for several years with no improvement, but that included whole soaked/sprouted grains and pulses. If trying “no grains”, how long does it take to notice if it will help? Weight is not a factor.

    Also, here is “cured of cancer” story, which some might find interesting.

    • Mary says

      Perlmutter has done a few podcasts (Robb Wolf’s and Jimmy Moore’s among them) and I remember specifically a question from a vegetarian. He claimed that his approach was definitely doable by a vegetarian. You would certainly not have to eat meat, although I think it would be difficult to eat optimally without eggs and dairy. Check out the podcasts if you can, and you might also want to check out The Vegetarian Myth, which is a book by a woman who switched from veganism to Paleo following neurological problems. I think there is also something on Youtube.

  72. Tom Boyer says

    #2 – There are many traditional cultures with high carb intake and low or nonexistent rates of neurological disease

    This is actually not true. Japan for instance — has a higher PERCENTAGE of their calories from carbs (rice). But their OVERALL consumption of carbs per capita is just a fraction of what Americans eat. People should most definitely not look at Japanese eating habits and conclude it’s healthy to eat that giant teriyaki rice bowl slathered in sugar sauce. Or rice cakes with syrup for breakfast. Nothing could be further from the truth.

    The one unifying concept that makes all of this make sense is the Insulin Hypothesis. It should be treated like the theory of evolution — it explains almost everything and it gives you many paths to good health.

    The research clearly is telling us: Keep your insulin levels down as much as possible, as long as possible.

    You can do that by avoiding foods (carbs) that spike your blood sugar levels and trigger insulin production. But you can also help by exercising to burn excess glucose and glycogen. You can help by doing what the traditional Japanese diet does — small portions, limited meals, no snacks. You can do it by making fasting part of your routine — say, skipping breakfast (which is surprisingly easy to do, and good for you, once you’re used to it).

    What made the traditional Japanese healthy wasn’t the rice. It was the fact that food was expensive in Japan so people ate small portions and didn’t snack.

    Whether you eat live cave man, or the traditional Japanese, or do Atkins, or become a running fanatic — your’e doing the same thing to your blood sugar. You are keeping it down and tamping it down. That is not that hard to understand, is it?

    • Mary says

      Good point. I lived in Japan for a year and the portion sizes are SO MUCH SMALLER than in the US. You get a little tiny bowl of rice with your dinner, which is probably about 1/5 of the typical carb servings in US restaurants. They also have a saying that you should stop eating before you are 100 percent full.

  73. Onur says

    Here’s the results of a study about consumption of different food categories and colorectal adenoma risk from Malaysia that seems like I could benefit from further explanation about:

    Soy bean and soy products were associated with a reduced risk for CRA (OR = 0.38, 95% CI = 0.15-0.98), while tubers were associated with increase in risk four-fold (OR = 4.14, 95% CI = 1.60-10.70) and red meat intake was found to increase the risk two and a half-fold (OR = 2.51, 95% CI = 1.02-6.28). Higher servings of fruits and vegetables were found to significantly decrease the risk (OR fruits = 0.47, 95% CI = 0.30-0.74; OR vegetables = 0.49, 95% = 0.29-0.80).

  74. Sean says

    Well, I’m in top shape, feel great, bloodwork is great. I eat a decent amount of carbs but most of my carbs come from long fermented sourdough bread. Interestingly enough there is some indication that sourdough actually helps to control blood sugar levels. Chris, what are your opinions on sourdough? Here are the basics of the research:

    “The study involved men between the ages of 50 and 60. They were given four different kinds of bread – white, whole wheat, whole wheat with barley, and sourdough white bread – and their levels of blood sugar and insulin were measured.

    “With the sourdough bread, the subjects’ blood sugar levels were lower, with a similar rise in blood insulin,” Graham says. “What was even more interesting was that this positive effect remained during their second meal and lasted even hours after.”

    And subjects did not have to eat additional bread at the later meal for the benefits to persist.

    The reason for this effect is not known for certain, but is probably the way the fermentation of the sourdough changes the starches in the bread, increasing its health benefits. Unlike most breads, which are leavened with yeast, sourdough bread is leavened with a “starter” bacterial culture that begins the fermentation process, giving the bread its familiar sourdough tang. ”

    So in reality, good fermented foods could allow for grain and carbohydrate consumption AND stabilize blood sugar levels it seems. A big issue I have with low carb diets is the “meat” side of it. I do not want to consume animal products if I can help it. Doesn’t animal protein come with it’s own set of health risks? Why would any diet plan advocate increasing consumption of it?

    Anyway, I am highly active and somewhat plant based diet, so without some carbs and my sourdough bread I would be starving mad. I can say without doubt once going on sourdough my digestion improved as well as energy levels. Wouldn’t it be a shame that some are missing out on something as beneficial as sourdough due to mislabeling of it as “bad”.

  75. matthew stevenson says

    I can appreciate the various arguments over this topic. 14 years ago I used ‘carbohydrates’ as a weight gaining fuel for wieghtlifting: and it worked – I gained 16 lbs. (muscle) in 10 weeks.
    Currently, I have been diagnosed with ALS. In no way do I feel ‘carbohydrates’ led to my demise. I still consume plain bagels, homemade bread, and baskets of fruit: and my condition is relatively ‘stable’.
    Consuming refined sugars is different than consuming carbohydrates. ALS is essentially the destruction of mitochondrial dna. Free radicals yield destruction, and refined sugars speed up this process.
    There are scrolls of chemicals and compounds in the foods we eat (preservatives, sweeteners…) which also fuel this destructive process, but no Dr. with an agenda would study this to any end.
    The resiliance of the human body is truly amazing, as many alcoholic chainsmokers usually die of loneliness rather than disease; but the evolution of mankind is in-debted to purity and simplicity of foods.

  76. says

    Carbs are starting to become the new bogeyman just like fats were before. However it all depends on what type of carbs you eat and what your activity levels are. People now days just sit around all day and no wonder they are going to get fat. In other societies, such as the ones mentioned above, with high percentage carb diets, people are usually slimmer and that is because of their lifestyle.

  77. Beth says

    Unfortunately, the wheat we’re eating now isn’t the wheat we evolved with. It has been extensively modified to grow shorter, be more disease resistant, etc. Check out “Wheat Belly” I think more study is needed, but I know since my 11 year old Asperger’s Syndrome son and I have gone gluten free, our stomaches are much happier. He went from having diahrrea 4-5 a week, to twice in the past 6 months. My husband and nuero-typical son still love gluten, but seem fine. I think we are so complex that nothing works the same for every body. More study is needed. Thanks!

  78. MaryAnn King says

    Non medical ind, but have read much of Dr Perlmutter’s book. I totally agree with your analysis. I know of a 95 year old man who works in a large car dealership that he started yrs ago and all he eats for lunch is a really large bowl of fruit all to himself and he is sharp as can be. On the other hand, my own mother has Demensia and i oversea her care and in knowing what type of eater she was earlier in life, I would say that she was on a high fat diet, was heavy, but I would not say I obese..

  79. Matt says

    With reference to point #2.
    “yams, tropical fruits, banana, papaya, sweet potato” are not grains.
    In his book (Called GRAIN Brain)
    He mentions Gluten and grains and lack of fats and essential fatty acids as being all contributors to neurological disorders, not high carb diet.
    He talks about VLCD as being a solution to diabetes and insulin resistance he also mentions that these are correlative and not necessarily causative.
    So the examples you cherry picked are beside the point and in fact support his argument as they were all absent of grain or gluten containing carbohydrate and mostly lower Gi than processed western carbohydrates.

  80. Michael says

    As someone with the beginning stages of autoimmune thyroid disease (high antibodies but hormones are still low-normal), I have had very bad side effects from low carb diets. I have tried LC and VLC on five occasions and each time I have developed depression, excessive tiredness, coldness of extremities, and even severe panic attacks. In my low carb diets I have always consumed sufficient micronutrients (lots of low-carb veggies and grass fed meats) as well as including MCTs from coconut oil and MCT oil.

    Thank you Chris for teaching me that low-carb diets are no good for people with autoimmune thyroid disease. I’ve been intentionally eating 100-200g of starchy carbs (minimal sugar) daily and I have been feeling a bit better.

  81. Maria says

    I am reading “grain brain” at the moment and my concern is how it goes against previous studies related to the consumption of high saturated fat,high cholesterol and cardio-vascular disease. I’m at risk of type 2 diabetes and metabolic syndrome as it is prevalent in my family. I have lost considerable weight with limiting my carbs but I’m wondering if my high intake of fat now will negatively impact my risk of metabolic syndrome. Eating fat for your brain heath is one thing, but increasing your risk of other diseases like cardi vascular is another. What is your thoughts on that ?

  82. Daryl says

    My husband and I read the book. We were both vegans for 25 years and after reading this book were convinced of the importance of adding eggs in our diet and more healthy fats like raw nuts and seeds. We cut out all grains, all starchy foods like potatoes, corn, rice. In 6 weeks we both lost weight, but more importantly than that we have only experienced GOOD results such as sleeping better and longer, our hair is not as dry and it’s more shiny, my fingernails don’t break as easily, our skin is healthier looking and overall we feel great. We eliminated more foods than we added to our diet. Only eggs we added in. We had always eaten healthy fats, but started eating them more. I still eat fruit, but not as much as before and my husband reduced his fruit intake much more than me. It makes sense to me as he says in his book that our brains need the fat. That the low fat diets are not healthy because our bodies need fat.

    Plus he even sites in his book that ancient grains are way different that the overly processed grains of today are. The grains even a couple of decades he says are different than today. The ancient grains were okay to eat, but today’s grains are different with all the gmo and pesticide use, etc. Is it any wonder there is a huge number of people with gluten intolerance and celiac disease? Not to mention obesity and diabetes. Grains turn to sugar and diabetics shouldn’t be eating them. The grain industry is a huge business. Just look at any grocery store there in an entire isle dedicated to just cereal and another to just bread! Now because so many people cannot consume gluten there are hundreds of gluten free products out there, however consuming those aren’t any better in terms of health. He says the foods they feed cattle (grains, corn, soy, oats…which they shouldn’t eat either as they are grass eaters by nature) are all designed to fatten the cows as quickly as possible in order to sell them. Hmmm eating those foods will fatten a cow so it stands to reason why there are so many obese people in this country too eating the same thing as the cows. If that puts the weight on cows quickly then it puts the weight on people quickly. He also mentions the fatter the person the smaller their brain is! I found that to be very interesting indeed!

    • sross says

      “Grains turn to sugar and diabetics shouldn’t be eating them.”

      As I mentioned, newer research shows sourdough based breads actually regulate blood sugar levels to normal throughout an entire day thus preventing any spikes. I won’t touch grain unless it’s been long fermented in sourdough cultures.

    • Alesea says

      It’s nice indeed that you experienced good results.
      But you need to be very objective when treating this topic.
      1. Not only grains are GMO but also vegetables and some fruits are. And also pesticides are used to grow them too.
      2. Even if you eat cabbage a whole week you will anyways have some sugar in your blood. Sugar is necessary for our body, the problem with it is when it’s high. Diabetics are allowed to eat either fruits and grains in limited amount.
      3. You cannot blame grains for weight gain. I went low carb at the beggining of this year and ate more fat instead (walnuts, coconut oil and dairy). In the beggining I lost some weight but after I gained more than I lost. I know people that eat a lot of bread and aren’t overweight but normal, and they’re not even exercising…Maybe U.S.A. really has some weird grains that are different from those we have here in Europe.
      Hope this helps!

  83. Frances Lilian Wellington - Kinesiologist says

    “Grain Brain” is next reference book on my study list.

    However, I can comment that for the followers here who are unsure of what their own carb tolerance level is, or whether their carb intake is excessive to their current/future needs, it is straightforward and quick to determine this through kinesiological manual muscle testing. Gathering such information takes the guesswork out of determining “What should I eat and how much, for how long?” (relative to one’s own specific current goal)… eg: What types of carbs best suit me? Will my body tolerate this type of carb? If so, how much? For what length of time? Such testing can show up very specific useful information… giving confidence in adjusting intakes up or down according to changing needs, specific to generic heritage, specific to increases/decreases in physical activity, specific to changing desires…. relative to an overall goal of optimal performance.

    What’s more, the way the testing is done (during a balancing session) the person’s perception of the adverse, neutral or beneficial “bodily sensations” any particular substance can have is rather obvious and therefore very educational.

    The most common “significantly out-of-whack” nutritional excess that shows up in my clients (who are generally moderately healthy yet slightly overweight middle aged people) is excess “carbs” (often 200 < 300% above their individual tolerance level). I don't witness this degree of excess in any other class of food.

    From my observations, in general, one in three people in my community probably ingest levels of carbohydrate in excess of their individual tolerance level and level of physical exertion.

    By excess I refer to "excess over and above their individual tolerance level"… one person's may be 60 grams, another's may be 100 grams per day. The body instinctively "knows" when there is an excess of any substance that has adverse consequences (of one kind or another). The body will reliably tell you what it does/does not want (for optimal performance) if you ask in the right manner.

    What is today's mild "moderately overweight" middle class suburban adult is fundamentally undiagnosed metabolic syndrome… left unchecked becomes something more chronic (diabetes)… left unchecked?? …well! there has to be a consequence of such a marked degree of nutritional imbalance, doesn't there?

    I would prefer to "nip things in the bud" with relevant education to prevent progression (& determining individual carb tolerance levels for example), at this stage of the game… in preference to reversing decline and attempting to bring about recovery 20 to 40 years down the track.

    I know the dominance of excessive low nutrient carbs being ingested in this community will have long term detrimental effects. There is no doubt in my mind.

    • Tom Boyer says

      I would encourage people who are curious about low-carb high-fat to just try it. Ignore the old wive’s tales (which are typically spread by the vegan and animal rights zealots). There is absolutely no data to suggest LCHF is harmful and a huge and growing pile of data that it is safe and tremendously effective.

      Just because Perlmutter has written a best-seller that is written for lay readers doesn’t mean anybody should underestimate him. Unlike Atkins, Perlmutter has top-tier scientific credentials in both neurology and nutrition science. There’s hardly anyone in the country better qualified than he to examine the relationship between diet and brain health.

      It doesn’t cost anything or require any great expertise — just a commitment to avoiding grains, sugary foods and starches. You can get your protein and fats a bunch of different ways; you can do this as a vegetarian (though difficult if you’re vegan).

      The worst side effect you have to worry about is lower blood pressure, which is actually a positive side effect except you you can feel faint or queasy while your body is adjusting. So most low-carb keto regimens encourage you to increase salt intake during the adjustment period. If you don’t feel well a couple of days into a low-carb regimen, just drink a little warm broth.

      After a few days as your body becomes keto-adapted, all sorts of wonderful things happen — your belly shrinks as you retain less water, you often stop snoring if you’re a snorer, acid reflux pretty much goes away. You have much less gas and indigestion. Once your digestive system settles in you will often be more regular.

      You will need less sleep, and if you’re exercising, you will actually have more sustained performance as your whole body learns to use ketone fuel. If you have a neurologically intensive job you may find your performance improves. Emotional performance can be better too — certainly it is better without blood sugar ups and downs.

      And I have found you don’t have to be low-carb all the time. You can enjoy these benefits even if you “fall off the wagon” once or twice a week. In our family we try to be very low-carb for about 5 days a week and then enjoy our beer/bread/chocolate during the other two days.

      It’s amazing to me that the low-carb movement gains momentum steadily — and with many different valid approaches — despite hostility from the medical establishment and the anti-meat crusaders. It is because people find out in their own lives that low-carb works. It just simply works.

      • beaker says

        My issue with “Hi Fat” is that often or mostly includes animal products. Now… if you are wealthy no problem you can eat free range healthy organic animal products. You can eat organic pasture fed butter and dairy, organic meats etc. But most people on this LCHF diet will be eating sick cage fed animals pumped full of god knows what. That is going to be more healthy that a predominantly plant based diet with vegetarian based fats? Can’t see that.

        • Tom Boyer says

          Beaker, if you want to have the best likelihood of good outcomes, you need to try to separate what is supposition, what is theory backed by a lot of good data, and what is proven.

          To argue that low carb requires spending $20 a pound for grass fed beef is a kind of a straw man argument and really is not supported by the data.

          Here’s what IS supported. We’re now up to 18 significant studies since the mid-90s that have validated the benefits of carbohydrate restriction for weight loss. That question should regarded as settled. The hard core deniers will never come around but they should be ignored just like climate change deniers.

          We also have extremely compelling evidence based on an ingenious study released in 2013 that a Mediterranean diet relatively high in fat (olive oil mainly) and relatively low in cereal grains produces good outcomes.

          By contrast there is supposition and good theory behind the idea of grass fed beef and free range poultry, but there not actually data yet proving that it is that much better for you than Perdue chicken and feedlot beef.

          If you want to spend the money for organic produce and grass fed meat, it can’t hurt and may benefit you but there isn’t actual study evidence proving it is effective in any way.

          Ethical vegetarians, vegans, committed environmentalists seem to want to fight low-carb because they fear its adoption would mean more meat consumption.

          But I don’t think anyone, even with good intentions, should be in the business of denying what the data says. It erodes one’s credibility in the long term.

          It would be better for vegeterians and vegans to focus on the myriad ways one can be meatless and also low-carb. I personally think red meat and butter belong in a good diet, but one can certainly achieve similar results with tofu and coconut oil. The point is to avoid pasta and sugar and margarine whether you’re carnivore or herbivore.

          Similarly, low-carb and exercise do not need to be seen in opposition in any way. One is not a substitute for the other.

          Studies of exercise as a weight-loss strategy have consistently failed to show success, but the data is overwhelming that exercise is good for you in dozens of other ways. If you want to follow what the data says, as opposed what various special interest groups want you to believe, the best approach is going to be low-carb AND exercise.

          • beaker says

            Tom, good to have your attention, you seem to know your stuff. I have no weight or health issues to consider. I’m 40yr, 165lbs, muscular build, predominantly plant based diet and exercise 6 days a week for 1.5hrs or so. Feel pretty awesome. I am curious of your thoughts on grains processed using sourdough cultures. I only eat grains long fermented in sourdough. Recent studies indicate better blood sugar stability for those eating sourdough. Those eating sourdough were stable all day vs. those eating non-sourdough having spikes all day. I think judging by how I feel (great) that a fair bit of long fermented sourdough daily is not bad. I tend to have 5 slices a day smeared with organic nut butters (brazil, almond, cashew). No brain fog here. I am full of enery, sleep well etc. I have 1-2 pasture fed hard boiled eggs a day, a lot of kidney beans for protein (also soaked and prepared properly), for dairy I have 24hr brewed yogurt that I make myself and 48 month aged cheddar. I eat a ton of steamed veggies. I have 2 bananas a day plus mixed berries. I am probably in violation of carb limits, but think something is to be said for properly processed grains. I don’t think anyone should be eating non-sourdough grains. My culture spends 48hrs fermenting the grains in a way I believe opens them up to benefits for the body. It is a shame that I never here sourdough mentioned in so many diet fads, hopefully research will continue.

            • Tom Boyer says

              Beaker, you might want to read Michael Pollan’s latest book, “Cooked,” a significant portion of which is devoted to fermentation and food.

              There are lots of good arguments, if not real study evidence, for the benefits of fermented food and eating active cultures to help maintain a good diverse gut flora. And frankly whether it’s good for you or not, I couldn’t live without good vinegar, cheese, salami, pickles…

              I would be a little skeptical that fermentation would do much to ameliorate the impact of bread on blood sugar and insulin levels. You should read Perlmutter and see whether you find his arguments persuasive, but he is arguing passionately that constant consumption of carbs — and the resulting constant elevation of blood sugar levels — is a major cause of a host of brain disorders including Alzheimer’s.

              Perlmutter argues that blood sugar levels considered normal in our society are actually quite high and damaging. We just all eat so many carbs that we don’t even know as a society what normal blood sugar looks like (i.e. blood sugar levels in societies that didn’t have such a plethora of cheap carb food).

              If you believe the insulin hypothesis — the idea that obesity, diabetes and much heart disease results from elevated blood sugar and insulin levels — then suddenly all kinds of foods marketed as healthy are really just the opposite.

              For example “whole wheat bread” — which is basically white bread flour supplemented with ground wheat husks — has a greater glycemic impact than a candy bar or a soda. Multi-grain bread products are delicious, but why are they marketed as healthy food in a society where the number one core health problem may be chronically elevated blood sugar.

              • beaker says

                Thanks Tom, I’ll check out that material. One thing that frustrates me about all these diets ‘backed by studies’ is studies simply can’t take into account certain individuals. Oh they try to say “we factored in for x lifestyle but I don’t buy it’. I’m 40 and fighting fit, actually also had a full cardio workup done last month and cardiologist said I was in the top 2% of heart health. Can they really say moderate levels of carbs are bad for someone that is lean, fit, exercises 1.5hrs a day, eats whole foods only, drinks 2 litres or more of RO water a day, avoids all junk foods, additives, etc. I am not likely the average person involved in most of these studies. I would like to see a study comprising of 2,000 of me to see what happens. I might buy a blood glucose monitor and spend a week or so monitoring and charting my levels. Overall I feel like the average person in these studies is probably far from fit, eats pre-packaged foods and refined carbs and who knows what else. I just find it hard to believe I feel so insanely great, as if I’m in my prime and am not on a LCHF diet. I’ll also note everyone in my family has lived to an old age. My Grandmother is 98 still drives and works part time. She’s sharp as a tack and certainly doesn’t restrict carbs to say the least. Anyway, will stop rambling.

                • Tom Boyer says

                  Beaker, I agree with you, everybody’s different and if what you’re doing seems to work, it probably is working.

                  I subscribe to the insulin hypothesis which says obesity is not from overeating per se (because everybody overeats); obesity is simply a symptom of metabolic syndrome — one’s body is struggling to deal with high blood sugar and insulin levels and is beginning to become insulin resistant. If you’re putting on weight, whatever you’re eating isn’t working. If you’re lean, that’s an indication that your body is tolerating carbohydrates well. Perlmutter goes further and suggests that even if you’re at a healthy weight, high blood sugar could be causing your brain to age faster. I don’t know if I believe that, but I sure hope it gets tested.

                  The only thing that seems obvious to me is that low-fat high-carb diets are a bad idea for people who are overweight. That’s like prescribing more cigarettes for people with early stage lung disease. If people are overweight, they need to heed their great-grandmother’s advice and cut the sugar and products made from wheat and corn.

        • Mary says

          Actually, it’s not necessary to really increase meat all that much. I too am on a very limited budget and I can’t afford high quality meat. I eat small amounts of the meat I can afford cooked with a lot of coconut oil and low carb vegetables. The one thing I definitely spend more on is high quality eggs. I very seldom eat chicken, because the cheap stuff is just so utterly disgusting.

  84. says

    I just saw Perlmutter’s interview on Fat Burning Man. He did say that his commendations were meat based. Personally I do not see that as needed. He also said that while he favored ketosis, he was not necessarily advocating it. I think someone could follow his protocol at higher levels of carbs than he would prefer.

    I do not think that grass fed meat is crucial, but I do think it important, and we are making that transition, starting with the item most important to that-liver. I have a feeling that a family avoiding McDonalds, fruit loops, lucky charms and snicker bars will probably save enough money to buy the grass fed meats. I would add that bones for broth would also be high priority for grass fed.

    • Tom Boyer says

      People have to remember that ketosis is not some exotic or risky thing. Burning fat is absolutely necessary to a healthy functioning human body — if you don’t eat a midnight snack, ketosis is how your body keeps your brain operating through the night.

      Perlmutter doesn’t talk about ketosis so much — his concern is brain health more than weight loss per se. But he is clearly arguing that ketones are a better fuel for human brains than glucose. When he speaks of miracle cures for people with brain disorders and emotional problems, what he is saying is that when patients switch over to ketone fuel, their brains often do much better.

      A super easy way to experience more ketosis in your life is to is just to not eat breakfast (which is normal practice in Mediterranean countries) or at least eat no carbs for breakfast — eggs, cheese and veggies for example. When you wake up in the morning, you are probably burning fat and you’re blood sugar is low and stable. Why not leave it that way for the morning at least.

  85. Tom Boyer says

    Re Kurt’s comments on carbs being necessary for “explosive” energy — as it turns out this is another kind of urban myth not supported by the data.

    In fact the L.A. Lakers, after a great deal of study, have gone very low carb in their approach to training, and found that even for professional athletes needing to perform at the very highest level, fat as fuel is much more effective than glucose fuel. If ketone fuel produces enough explosiveness for NBA athletes it’s going to be plenty explosive for you and me.

    There’s great work being done in this subject by people like Jeff Volek (who has been working in the field of nutrition for athletic performance for decades) and Peter Attia (a physician who is a huge fitness buff).

    I have not read the research in detail, but my sense is that for sprint-type events at a very high level of performance, carbs may give you a little bit of an edge. But for everything else, low carb or no carb may well be better.

    Certainly in my experience when I’m in full ketosis, I have much better endurance on my bike rides — ketosis is like being in your second wind all the time — there is no hitting the wall experience whatsoever because your blood sugar levels start low and stay low.

    Finally there is interesting historical data. The Masai, certain Plains Indians, and the Inuit lived almost entirely on high fat meat, fish and blubber despite the fact that their lifestyle required tremendous physical strength and endurance. And their health, as documented by westerners who visited them, was exemplary in the years before western flour and sugar began making its way into their diet.

    • Mary says

      Nicely stated. I also highly recommend the lectures by Peter Attia on ketogenic diets. He is a major fitness buff and has noticed that his swimming performance on the sprint swims is a tad slower, but that other than that his performance equal or better. He feels that the tradeoff is well worth it, as all his health markers are stellar.

  86. Tom Boyer says

    I think at this point the data strongly supports limiting carbs — but what that limit should be probably depends on the individual person. In fact that was one of the features of the original Atkins diet 40 years ago.

    Atkins wasn’t telling people to eat no carbs. His approach was for each person to gradually phase carbs back in, and as long as they didn’t start bloating or putting on weight, that was the sign their body was tolerating the carbs well.

    So whether you’re at 20 grams a day or 150 grams a day doesn’t matter as long as it works for you. And it may not matter terribly what the carbs look like. Maybe you love beer, or bananas, or beans, or pastry — enjoy it but budget your consumption.

    The only thing I take issue with is a suggestion that it’s unhealthy to be at the lower limit or that you somehow need sugary fruit or beans or whatever to be healthy.

    There really isn’t any evidence that we’ll get sick if we don’t get carbs — especially in contrast with the very strong evidence that eating too much carb food — mostly the processed grain products and sugar that the American food industry churns out — destroys our health in myriad ways.

  87. al cool says

    Well, you make the same points that have supported the anti-low carb people for years and our society is still fat, diabetic and addicted to sugar. And now we have passed this carb-based diet onto our obese children. Hmmmm

    The small tribes you mention above? Living in poverty in a rain forest? Really? Pick a set in downtown LA, London, Tokyo, Peking, Rio, then show me your conclusions.

  88. Robin Sommer says

    First, I am very impressed with the thoughtfulness of many of the people that have responded here. It is indeed unfortunate that the medical community does not seem to have the same integrity, open-mindedness, and the in-depth critical thinking that one would assume would go along with their profession, especially considering how much they charge for their services. (truly they seem to be the last to know about nutritional research) I came across this blog as a function of having just watched and being disillusioned by Dr. Oz’s show on the dangers of eating all carbohydrates. Time and again he never feels he has to substantiate nutritional opinions with research (as in citing particular studies), no exception with their claims about eating fruit and complex carbohydrates. Beyond that he never entertained the rather obvious idea that cross cultural studies would assuredly blow a hole in their theory that all carbohydrates are “bad”. There was no mention of high insulin levels causing the inflammation, nor did they ever speculate that the damage to the brain was possibly the result of gluten.

  89. Cynthia says

    Back in the 70′s when I was a teenager- before I was aware and had two degrees I noticed when Mom cooked chicken, green beans and potatoes, I was always better off losing the TATERS. I still am.

  90. beaker says

    It’s almost as if some are saying everyone that eats moderate carbs is obese? How do you explain people like me who work out 6 days a week, eat a variety of whole foods + moderate (sometimes high) carbs and are slim/atheletic. If carbs were as evil as presumed, being 40 I should be massive by now but I have virtually no body fat, very lean 165lbs. Mind you if I do eat “carbs” they are whole food based carbs, not refined crap from a packet. My wife has more carbs than I do and she is 105lbs, fit, atheletic and 43. I would like to see studies of people like my wife and I who eat well, eat plenty of carbs, exercise a great deal, etc.

    I have a theory about this carb war and exactly what it is and why nearly everyone has it wrong. I believe that poor diet and lifestyle choices cause vast changes in the gut microbiome. Once these changes take hold your biome will contribute to Obesity, brain issues, inflammation, mental disorders, arthritis and much more. If you eat a wholesome diet, exercise, reduce stress, eat fermented foods (sourdoughs, yogurts and more) you keep a beneficial gut biome in check. There are no insulin issues, obesity issues etc. I don’t think carbs are to blame, I think it’s a sedentary lifestyle + the wrongs foods (tending to be refined carbs) that drastically alter the gut biome and BAM, you’re in big trouble. Bad gut bacteria feed on refined carbs and sugar, pushing out the good bugs. This is one reason behind IBS and other bowel disorders. New research is already showing Obese have far different gut biomes to skinny atheletic people. Things like the microbiome project are going to turn current nutritional thinking on it’s head. This Grain Brain book will be obsolete very soon when the root cause (the gut biome) is fully realized. We must eat to feed the good bugs and starve the bad bugs.

    • says

      Totally agree that it is more about feeding our gut flora than anything else- this has been my primary focus for our family for the last 5 years- and it really works.

      We did a grain free, moderate carbohydrate diet (GAPS) to heal our guts and it was very helpful. We healed behavioral issues in our now 6 year old. Allergy issues in me. And auto immune issues in my husband.

      But, in the long term, I needed more carbs. So, following a WAPF Diet has been hugely beneficial to me in healing my adrenal issues that arose from years of vegetarianism and later too low carb on GAPS.

      I also think that the psychological effects of constant deprivation from carbs goes unrecognized. Food can create all kinds of stressful situations in life because we gather around food. Everything social involves food. I am not saying we should all be eating store bought cake with food colored frosting or store bought potato salad with seed oil, but for our family, eliminating grains entirely makes for way too many awkward situations with kids and stress with extended family. Anyway, ending this long soliloquy, I agree with much of what you’ve said, I think some people get trapped in black and white and begin to respond out of fear- they fear carbs because of all these studies and stop listening to their bodies. I think some can thrive on a low-moderate carb diet and others may need more, And this is not a bad thing if their blood sugar can handle it. And for these people who need more, it can actually be harmful to stay too hard line against carbs. There are hundreds of testimonials of people going into adrenal crisis, which then sets of hormonal or thyroid issues as their bodies try to compensate for lack of carbs.

    • Patti says

      I couldn’t agree more. After reading and learning about nutrition over the past two and a half years, I’ve come to believe that many of our health problems would improve with a more “whole foods” based diet. The reason so many people experience benefits on low carb diets is because eating that way requires removing most processed foods from the diet. But is it necessary to restrict carbs like that? Would one still benefit if they cut out the junk but still ate carbs?
      I know I felt great at first on a LCHF diet, but over time, my metabolism dropped and I had no energy at all. Increasing carbs (but still avoiding processed garbage) IMPROVED my health. It’s not the carbs! It’s the junk!
      I don’t know why LCHF advocates have such a hard time believing that many people actually thrive on higher carbs. I don’t care if they stay low carb if it works for them. Why should they care if I eat higher carb if it works for me?
      And I am an average sized 52 year old female with no known health problems. I lost over 30 pounds when I went LCHF and I haven’t gained it back since adding quality carbs.

  91. greensleeves says

    Sorry Chris I absolutely cannot believe we read the same book. Did you get a partial version or something?

    Perlmutter clearly says to eat vegetables & non-gluten grains. On page 5 a paragraph begins “Eat your vegetables.”

    On page 129 he says “eat. . .a wonderful abundance of vegetables.”

    On page 226 he offers a list of vegetables to eat as much of as possible, including all kinds of leafy greens & even includes things like starchy water chestnuts.

    On page 227 he supports occasional consumption of 1/2 cup servings of things like teff, sorghum, rice, tapioca, quinoa. This makes him more liberal and open in the starch department than even Jaminet, I believe.

    I urge you to reconcile your post with the final version of the book. Best wishes.

  92. Tom Boyer says

    Beaker writes: It’s almost as if some are saying everyone that eats moderate carbs is obese? How do you explain people like me who work out 6 days a week, eat a variety of whole foods + moderate (sometimes high) carbs and are slim/atheletic.

    Obviously not all people who eat a carb-based diet are obese. If your diet is working for you, that’s great. I know young people who live largely on pizza, Doritos, burritos, candy bars and beer, and maintain a healthy weight. Doesn’t mean that diet works for most people.

    What I would assert are two things: If you are struggling with weight, blood pressure, bloating, acid reflux, high blood sugar, afternoon drowsiness, snoring, high triglicerides, difficulties with memory — all these things are symptoms of metabolic syndrome, and the research of the last 20 years tells us — quite clearly — that the best intervention is to cut down on carb consumption. Exercise is good, exercise is helpful, but exercise will NOT, by itself, turn an obese person into a fit one. The data is abundantly clear on that point: Exercise does not lead to weight loss, contrary to conventional wisdom.

    The other thing Beaker is suggesting that I take issue with is the idea that “healthy” carbs — presumably fresh fruit and “whole grain” wheat products — are a lot better for you than “unhealthy” carbs like pizza or french fries. If your problem is too many grams of carbs, switching from white bread bagels to wheat bagels does not help at all! Switching from coke to organic fruit juice does not help! Sugar is sugar. Wheat is wheat. Organic starch is essentially the same thing as industrial starch.

    As a matter of taste I like whole grain baked goods but, despite the enormous amount of marketing behind them, there really is no solid evidence that whole grains are particularly good for you.

    In fact whole grains raise your blood sugar for a longer period of time than sugar or white flour. For
    someone whose problems are caused by elevated blood sugar, that may not be a good thing.

    As counter-intuitive as it is, having a Hershey bar for breakfast might actually be better for you than a “whole grain” and “organic” blueberry muffin, because the candy bar’s impact on blood sugar would at least be short-lived. The best breakfast, for anyone who wants to control blood sugar (which is most of us), would be foods that do not jack up your blood sugar at all. Or of course no morning meal at all, which is one of the less talked about features of the Mediterranean diet.

    Getting back to Beaker — if whole grains, fruit and exercise works for you, that’s great. Just don’t try to impose that solution on the entire population — that’s what the American diet establishment tried to do, and the result was (and is) a public health calamity in the United States.

    • says

      Hi Tom,
      Beaker was actually speaking about sourdough breads and he went on to say that he didn’t think anyone should eat grains that had not been properly prepared (ie soured). Souring greatly reduces reduces phytates, predigests starches and has been shown to improve glucose metabolism in compromised individuals. I think he would agree with you that eating a whole wheat bagel for breakfast is a bad idea.

      Do you agree that there is a difference in properly prepared, organic grains and conventional breads?

      I do think that many people cannot tolerate grains (properly prepared or not) at all, but there are some of us who do better on a diet which includes some. I guess the part of this whole debate that bothers me is that people seem to fail to recognize that there is more than one possible answer. I can honestly say I have used and value both a grain free, moderate carbohydrate diet and one that includes carbs. i think it’s important to recognize that carbs are not evil. Grains, properly prepared, are not evil. And we are all designed differently. Even the same individual will have different carbohydrate needs at different points in their life. It is not a black and white issue.
      Here is a study for reference:

      • Tom Boyer says

        Regarding use of fermentation on grains — I’m skeptical until I see data. The core thing I believe is that most Americans need to focus on keeping their blood sugar down — that’s how we maintain weight and reduce our cardiovascular risk.

        IF it is true that keeping blood sugar down, and insulin levels low, is the most important thing, then whether your wheat is fermented, or organic, or includes the husks may not matter all that much.

        Carbs drive blood sugar which drives insulin which drives body fat. Elevated insulin is the devil.

        The gut biome is important, but to me it’s secondary to keeping insulin levels low. Nevertheless the research on biome has only really just begun, so who knows — I wouldn’t be surprised if you can improve your cardio risk factors by eating live-culture sauerkraut.

        I’d encourage people to read Gary Taubes — “Good Calories, Bad Calories” is probably the most detailed discussion of the insulin hypothesis that you can find. Taubes may be wrong, and he admits he may be wrong — which is one of the things I like about him. But the recent research seems to point in that direction. Blood sugar seems to be of paramount importance.

        • Marc Strumpf says

          I am on the same page as Tom. Keeping insulin low is paramount. However one word in defense of the WAPF diet that would have you ferment grains.

          Compared to the Standard American Diet (SAD) a WAPF diet is light years ahead. Grains are consumed fermented which adds valuable enzymes and other things to your system which are valuable.

          A certain portion of our diet should be raw but this goes against the American pallet. Fermented foods are “Super Raw” and add nutrients that are hard to find elsewhere.

          A WAPF type diet with limited grains only eaten if fermented is a fine diet especially when compared to S.A.D.. The problem is that you will have a hard time switching to ketones for energy if you eat too many grains even fermented.

  93. Marc Strumpf says

    Technically, there is no essential human requirement for carbohydrates in the diet. The liver can make all the glucose we need to maintain proper functioning without eating a single carb. Therefore, there really is no such thing as a diet too low in carbs.
    Rather, we may have impaired digestion from eating the Standard American Diet for our entire life. We can also get accustomed to the feeling we get from fueling our energy from carbs/sugar. We may like the fast energy like being on rocket fuel. But at the end of the day, if we can adapt our bodies to running on ketones and get a nice slow burn of energy without spiking insulin we are much better off.

    • Chris Kresser says

      The fact that the liver can produce carbohydrate from other substrates is better viewed as evidence of how important glucose is to physiological function rather than an argument against eating carbs. That has never made any sense at all to me. There’s no evidence at all (as I’ve pointed out many times) that being in ketosis is optimal for healthy people, though it is effective as a therapeutic approach in some conditions.

      • Tom Boyer says

        I think what Chris is referring to with the liver is ketones.

        In the absence of glucose, when glygogen stores are depleted, the liver processes fat (dietary fat or body fat) into ketones — which is essentially a second fuel the body and brain can live on. This is ketosis. Far from being an inferior fuel, there is evidence that the brain functions BETTER on ketones — cognitive function improves, and a variety of brain disorders see a lessening of symptoms. This is also why low-carb dieters generally report feeling more alert and needing less sleep.

        Perlmutter’s core theory, which is certainly unproven but very plausible, is that ketosis is critical for the brain’s maintenance and regenerative function. But unfortunately most Americans don’t get to experience ketosis much because they are told by their doctors that it is healthy to constantly stuff themselves with “low-fat” sugar and processed grain products.

        With all due respect to Chris, there is a lot of evidence that ketosis is a normal and healthy human condition. If you don’t reach ketosis, you can never burn body fat, only spend your life accumulating it — which unfortunate is how it is with 80 million obese Americans.

        • says

          I was saddened to read Chris’s comments in the recent article, “This Is Your Brain on Gluten” in The Atlantic.

          Rather than hearing our comments, he seems to be even more firmly entrenched into his position. I get the feeling that being “right” means more than fully exploring or understanding the issue.

          At least here, he acknowledges the benefits of ketosis for some populations. “First of all, I’d like to point out that very low carb (VLC) and ketogenic diets can be effective therapeutic tools for treating many neurological disorders.” BUT, he (perhaps correctly) questions the wisdom of applying this approach to all patients.

          In the more recent article, he reduces the scientific basis for this dietary intervention to one rat study showing effectiveness in Parkinson’s patients and a single small study showing “some” effectiveness in “some” patients with dementia. As a patient at high risk of Alzheimer’s, I find his dismissal disingenuous, at best. I can find hundreds of studies and decades of clinical practice backing up Dr. Perlmutter’s approach. So could he… just by reading the book.

          Chris then goes on to say “It’s important to realize, that just because a low-carb diet can help treat neurological disorders, doesn’t mean the carbs caused the disorder in the first place.” Once again, I think Chris is missing the point. Dr. Perlmutter, as a neurologist who’s devoted his life to preventing neurodegenerative disease- like Alzheimer’s- is keenly aware of it’s multifactorial etiology. Keeping blood glucose low is simply one factor we CAN control; Dr. Perlmutter is suggesting we should.

          Chris then cites the Kitivans and other similar traditional groups as “proof” that carbohydrates are healthy without acknowledging that the quality of the carbohydrates they consume (much lower in glucose than our hybridized versions of the same) and the vast difference in their lifestyle (much more physically active than the typical Westerner) most certainly plays a part in their tolerance level. Kitivans also get the majority of their protein from the sea; rich in Omega 3s. Their fat is almost all SFA from coconuts- falling fairly closely in line with what Dr. Perlmutter recommends.

          In Chris’s defense, as Dr. Perlmutter’s publicity tour commenced, he DID seem to become more restrictive of carbs. As his patient (of almost a year) I was told to keep my intake under 75 grams. I now see he’s lowered his recommendations to 60 grams. I eat somewhere in between and my plate is piled high in vegetables, hardly VLC.

          Rather than attacking Dr. Perlmutter’s approach which is VERY controversial for my population (ApoE4/4), I would greatly appreciate his take on what he would do to prevent Alzheimer’s knowing he was at very high risk. Stop hating, Chris. Work on the problem with us.

          • Jake Ivey says

            {“I would greatly appreciate his take on what he would do to prevent Alzheimer’s knowing he was at very high risk.”}

            I’m not Chris, but in addition to what you’re already doing, I’d make sure I was eating at least 3 Tbsp. of Coconut Oil/day, taking plenty of Tumeric and a few other herbs, plenty of bioavailable B12, and so on.

            What great is, like all good holistic protocols, you’re working on preventing Alzheimer’s, but at the same time doing so many other good things for your body.

          • Mary says

            It’s become crystal clear to me that Chris is not interested in an open-minded discussion of Dr. Perlmutter’s recommendations, or the views of people who can benefit from an inexpensive, self-managed preventive approach involving drastically cutting carbs from all sources. He is interested in driving internet surfers to his site, and his book. I personally have chosen a ketogenic diet for now, but I am interested in hearing about pros and cons from people who are willing/able to really look into the research and debate openly about the benefits and possible risks. Instead Chris just keeps saying “there is no evidence that whole fool carbohydrates contribute to neurodegeneration” when everyone with a brain knows full well that many whole food carbs (starches) can have a very significant impact on blood sugar, and therefore could be very much of a problem for many, many people. I guess he would have everyone eat whole-food carbs to their heart’s content until they begin to suffer problems, at which time he would recommend they find an integrative medicine practitioner and shell out 1000+ bucks on expensive consultations and tests. Many people fault the Paleo movement with being a bit elitist–a diet for rich folks who are starting out so much healthier than the rest of us and can easily afford grass-fed meat/butter etc. and fancy gyms and trainers (and launch parties). No wonder Chris Kresser is the darling of this movement. I’ll take Dr. Perlmutter’s preventative approach for the rest of us any day.

          • beaker says

            I would also do around 30-45mins a day of moderate cardio exercise. This has shown a protective effect on the brain iirc.

          • says

            I’d just like to point out that the quotes in The Atlantic are word-for-word from this article; I’m guessing those weren’t new, unique comments from Chris that they got during an interview or anything.

            As to whether whole-food carbs cause neurological diseases, I think the point was that if you don’t have issues with blood sugar or metabolizing carbs, whole-food carbs aren’t a problem. If a person can’t metabolize carbs without experiencing huge blood sugar spikes and dips, it’s pretty clear that a lower-carb approach is probably better for them (at least temporarily).

            • says

              Thanks for your thoughtful responses. Jake, you KNOW as Dr. Perlmutter’s patient, I’m on an awesome supplement regimen, including curcumin, B-12 and many others. And, Beaker- right on with the exercise recommendation.

              The coconut oil regimen, however, is controversial for my genotype as carriers of ApoE4 tend to hyperabsorb cholesterol. Some get really high LDL-Ps with higher fats, especially SFA. I’m still mildly keto-adapted, but use primarily MUFAs and some limited SFA. Also, Dr. Samuel Henderson’s large body of work (not ONE study) has shown inconsistent/disappointing results with a ketogenic diet for ApoE4 carriers.

              Our population truly is the modern day canary in the coal mine. We live with the knowledge that we have a great likelihood of developing Alzheimer’s with NO consensus from the medical community on the best preventative diet. Most docs (like Dr. William Davis) advise low-fat. Others, like Perlmutter, advise the opposite. Drs. Dayspring, Attia, Jaminet have hinted they concur with Dr. Perlmutter for E4s…but no one has tackled the issue head-on. To date there are NO studies that have separated subjects by ApoE genotype and tested a quality HFLC diet on humans with regards to preventing dementia. Instead Big Pharma spends millions of dollars on one failed drug after another.

              Alyssa, re-read both articles. They are similar, but different, quotes. Chris appears to be dialing back his support of a ketogenic diet for even high-risk patients by minimizing the scientific groundwork that has already taken place…perhaps he’s unaware???

              Mary, I hope you’re wrong about Chris’s disinterest. Resolving the conflicting dietary advice to prevent Alzheimer’s is a big issue for ApoE4 carriers (25% of the population), especially homozygotes like me (2% of the population) and other high-risk folks. We could use his help in figuring out what DOES work.

              • says

                No, the quotes are exactly the same. From the article above: “It’s important to realize that just because a low-carb diet can help treat neurological disorders, doesn’t mean the carbs caused the disorder in the first place.”

                From the Atlantic: ““It’s important to realize,” Kresser says, “that just because a low-carb diet can help treat neurological disorders, doesn’t mean the carbs caused the disorder in the first place.””

                From the article: “[T]he Hadza of north-central Tanzania and the Kuna of Panama obtain a high percentage of their total calories from foods that are high in natural sugars, such as fruit, starchy tubers and honey, yet they are remarkably lean, fit and free of modern disease.”

                From the Atlantic: ““The Hadza of north-central Tanzania and the Kuna of Panama obtain a high percentage of their total calories from foods that are high in natural sugars, such as fruit, starchy tubers and honey, yet they are remarkably lean, fit and free of modern disease.””

                From the article: “All of these cultures are fit and lean with practically non-existent rates of neurological disorders and other modern chronic disease.”

                From the Atlantic: ““All of these cultures,” Kresser notes, citing Swedish researcher Staffan Lindeberg’s book Food and Western Disease (and, I would add, Dan Buettner’s The Blue Zones) “are fit and lean with practically non-existent rates of neurological disorders and other modern chronic disease.””

                Plus, they introduce the section by saying “He wrote recently on his website about how he responds,” so it’s pretty clear they just took quotes from this article.

                I suppose it doesn’t make much difference either way; I just wanted to point that out :) And I highly doubt Chris is disinterested; I think he’s just busy.

                • says

                  Alyssa, you are correct; there are many similarities between the two articles. BUT what prompted me to post was Chris’s dialing back his support for a ketogenic approach in The Atlantic article.

                  Perhaps, I’m splitting hairs (forgive me if I am), but after literally hundreds of posts in support and defense of Dr. Perlmutter, (more comments than ANY other blog post) Chris seems to be moving in the OPPOSITE direction by minimizing the scientific evidence.

                  From this blog post:

                  First of all, I’d like to point out that very low carb (VLC) and ketogenic diets can be effective therapeutic tools for treating many neurological disorders. I touched on this briefly a while back in my podcast with Emily Deans, and initial studies on low-carb diets and mental health have shown promise. (1, 2, 3, 4) Because Dr. Perlmutter is a neurologist, it makes sense that he would be a proponent of low-carb diets for his patients based on these therapeutic effects.”

                  From The Atlantic:

                  Kresser tells his patients that initial studies on low-carb diets and mental health have shown promise. He notes scientific articles that look at why low-carb diets are sometimes effective in managing epilepsy, rat models that have shown positive effects in Parkinson’s, and a small study that showed some cognitive improvement in patients with dementia.

                  With all due respect, there is a much larger body of work in support of this dietary approach, not just ONE rat study and a single SMALL study in humans. By minimizing the scientific evidence, Chris seems to be withdrawing his already tepid support.

              • Jake Ivey says

                Julie, I figured you were on a good supplement protocol, but always good to hear.

                As to the tendency to hyperabsorb cholesterol, I’d be interested in how that is managed with ApoE4 carriers, as I would think the last thing you’d want in an Alzheimer’s prevention protocol would be a controlled, low cholesterol.

                • says

                  Very astute observation, Jake. I’m interested in figuring that out too.; my very life depends upon it :-)

                  My best guess, at this point, is that higher cholesterol may be optimal for E4s. We know that our version of apolipoprotein carries and delivers cholesterol less efficiently than other ApoE genotypes. For that reason alone, limiting this vital fuel makes little sense. However, ApoE4 also CLEARS lipid depleted apoliprotein less efficiently than other genotypes; which could be an argument for limiting fat intake. While consuming a ketogenic diet, we BURN lipids as fuel which may ultimately prove to be the best clearance mechanism.
                  There is a body of work, led by Drs. Neal Barnard, Rudy Tanzi suggesting that maintaining very low cholesterol levels, and little to no animal products, is the best dietary prevention strategy for preventing Alzheimer’s. This is based upon interventions, in which animals fed high cholesterol diets, developed high levels of amyloid-beta plaque. (Similar interventions in humans have been mixed.)

                  For now, we observe that E4 carriers tend to develop high TC, LDL-C and LDL-P when consuming a higher fat diet. Some, like Dr. Stephanie Seneff and Chris Masterjohn, suggest that’s because we NEED the higher levels. Conventional wisdom, however, still advises us to eat a low-fat and/or take statins.

                  Why should Chris or anyone who doesn’t carry ApoE4 care? My guess is that figuring out what works for our population may unravel the Alzheimer’s prevention puzzle for EVERYONE. Alzheimer’s currently affects over 5 million people in the United States alone. As our population ages, experts estimate that more than 14 million Americans will develop the disease by 2050. The ApoE4 variant is the strongest genetic risk factor for late-onset Alzhimers. Almost all E4 homozygotes, like me, will go on to develop the disease.

                  E4 carriers are navigating our dietary path without a map. There is NO consensus from the medical establishment for us. We are on the precipice of an epigenetic brave new world, one step ahead of the scientific community. If this canary is still tweeting in about ten years; I may have taught you all that a mildly ketogenic diet IS a viable prevention strategy for everyone.

              • Jake Ivey says

                {” E4 carriers tend to develop high TC, LDL-C and LDL-P when consuming a higher fat diet. “}

                Julie, what exactly do you mean by high TC, LDL-C, & LDL-P? What ranges are you referring to, and what do the overall lipid numbers look like?

                • says

                  Jake, if you look within the Paleo community, you’ll find about one fourth of folks who begin the diet are impacted with previously unseen high LDL-C and LDL-P. Not surprisingly, many are found to carry the ApoE4 allele. Some argue, these high numbers are suggestive that a HFLC diet is inappropriate for this population. Those who disagree have yet to tell us what a good lipid profile for an ApoE4 carrier looks like.

                  I was generally unwell, “functionally ill” for much of my life when I subscribed to the low fat dogma. I always had LDL around 80. Since greatly increasing my my dietary fat to around 65% of my calories my LDL has skyrocketed to 150, TC of 250. Fortunately, the rest of my numbers are ideal and my LDL-P is discordant (in a good way) at 1,100. Other E4s aren’t so lucky. Many end up with LDL-Ps in the 2,000s.

                  As you know, high LDL-Ps are correlated with greater risk of CVD…what implications does this have for the E4 community? Should we be eating less fat, more carbs- driving up small LDL-P and LPIR- to keep LDL-P down? Many of us are struggling to find the right combo and ratios of healthy fats to be both neuro and cardio-protective. We’d greatly appreciate having some experts, like Chris, weigh in on our dilemma.

          • says

            “In the more recent article, he reduces the scientific basis for this dietary intervention to one rat study showing effectiveness in Parkinson’s patients and a single small study showing “some” effectiveness in “some” patients with dementia.”

            To be fair, it appears to me that the author of this article in The Atlantic was probably just rehashing what Chris had said in the original article, and used his own language to describe the 4 different citations Chris listed in that opening paragraph. I don’t think Chris was actually interviewed, but I could be wrong.

            The point is that Chris doesn’t believe that everyone should be on a low carb diet “or else”. I haven’t read the Grain Brain book yet, but I recently saw Dr. Perlmutter on Dr. Oz suggesting that EVERYONE should eat low carb to prevent neurodegeneration. I think that’s Chris’s main point here, that whole-food carbs don’t necessarily cause neurodegeneration, and that keeping carbs under 60 g/day is not necessary for the public at large. Especially for those people eating a nutrient dense, moderate carbohydrate diet

            Also, I think Chris would agree that Americans should increase their activity and eat more fatty fish, since those are some of the main recommendations he makes time and time again. I would bet that Chris would suggest that all Americans focus more on those two risk factors (inactivity and inflammatory diets) before they skip right to a <60g carb diet.

            Ultimately, the point here is that there is no one-size-fits-all approach to nutrition and health, and if Dr. Perlmutter is suggesting that ALL people consume a low-carb diet no matter what their situation, then I think Chris is right to critique his recommendations.

      • Marc Strumpf says

        The point I want to make is that you cant classify carbohydrate as an “Essential Nutrient” Essential nutrients are those that we must eat because our bodies can not manufacture them.

        Carbs do not fall into that category. In fact, our liver can and will make all the glucose we need for proper functioning.

        That does not detract from the importance of glucose to the proper functioning of our systems.We must have it, so our bodies make it. No additional glucose is really necessary. Once our muscles and brain have their max fill, the body turns it into fat.
        Burning fat for energy rather than glucose is far more efficient than burning sugar. I would suggest reviewing the work of Nora Gadgaudes, Stephen Phinny and Jeff Volek for for the scientific evidence that this is true.

        • PC says

          It’s not about the glucose. It’s about the other things that carb-rich foods contain. Our bodies need more than just fat, protein and glucose.

          • Tom Boyer says

            PC asked: Perhaps it’s what carb-rich foods contain that is truly important – the antioxidants. Maybe that’s why we have a taste for them?

            That’s a hard question to answer. Carb food can contain a lot of things. I wonder which of these are essential for human health:

            Whole corn, vegetable oil (contains one or more of the following: corn, soybean, and/or sunflower oil), salt, cheddar cheese (cultured milk, salt, enzymes), maltodextrin, wheat flour, whey, monsodium glutamate, buttermilk solids, romano cheese from cow’s milk (part-skim cow’s milk, cheese cultures, salt, enzymes), whey protein concentrate, onion powder, partially hydrogenated soybean and cottonseed oil, corn flour, disodium phosphate, lactose, natural and artificial flavor, dextrose, tomato powder, spices, lactic acid, artificial color (including yellow 6, yellow 5, red 40), citric acid, sugar, garlic powder, red and green bell peppe powder, sodium casinate, disodium inosinate, disodium guanylate, nonfat milk solids, whey protein isolate, and corn syrup solids.

            That is the ingredients list for Doritos (Nacho Cheese), which I get cravings for all the time. I wonder which of these chemicals my body is crying out for?

            Or might it just be the blood sugar rush I get when I down a bunch of processed and heavily flavored corn meal, washed down with water and corn syrup and caramel color?

            I’ll take my tongue out of cheek. The reason carb food is so addictive is NOT because it is nutritious. It is no more nutritious than cigarettes. Carbs food is addictive because it is addictive. What is nutritious about french fries, coke, ice cream, crackers, “multi-grain” sugar cereal, sugared yogurt, fruit juice and twinkies — which most of us crave like a smoker craves nicotine.

            Carb food is highly, highly addictive, which is what makes it so dang profitable — you can add sugar to carbonated water and sell it for $1 a liter. You can mash up corn and wheat for pennies a pound and sell it as “heart-healthy multigrain” products and people can’t stop eating it.

            • Patti says

              I hardly think using Doritoes as an example of carbs is a good example. I eat white potatoes (with real butter and real sour cream). I enjoy them but I don’t find them addictive. In fact, when I was eating LCHF and NOT eating potatoes, I had cravings for carbs. Now that I’m eating a moderate amount of carbs, I no longer have cravings of any kind. My appetite is under my control. I eat when I’m hungry and I stop when I’m satisfied.

              • Bruce Wilson says

                Right. Your craved carbs, and when you ate them, the craving goes away. Just like a smoker’s cravings for nicotine go away when they smoke a cigarette.

            • Bruce Wilson says


              I think this is smoking gun. I have been following this debate for the last few months, and have been amazed by the level of rhetorical gymnastics going on. It reminds me of the same debates I would engage with addicts, and maybe not surprisingly, with diabetics who refuse to lower their carb intake, because they like the “buzz” they get. I am still amazed by how many people complain about cravings for carbs/fruit, but not about protein/fat cravings. Now why is that?

  94. Ann says

    Hate to jump in here but I would like to counter this with Dr. Schwarzbein’s view who is an endocrinologist in Santa Barbara who manages her patients blood sugars, etc by optimizing their hormones. She lectured where I was studying and she advocates eating just enough carbs to maintaining the building functions (anabolic) of the body. When the liver has to create energy, that is a catabolic state – which over the long run leads to aging and stress on the body which has a cascade of consequences. For those interested her website is:
    Her first book is really informative.

  95. beaker says

    I think studies can be cherry picked to show just about anything. Here is one highlighting increased risk of death for those on low carbohydrate diets:

    Low-carbohydrate diets were associated with a significantly higher risk of all-cause mortality and they were not significantly associated with a risk of CVD mortality and incidence.

    Then there is this recent news about reproducibility of scientific studies:
    “The Truth Is Many Scientific Studies Can’t Be Trusted”

    So where does this leave us? Plenty of info to claim LCD causes early death, that Ketosis long term causes Liver and Kidney damage, that HCD causes problems AND that most studies in some cases 88%!! can’t be reproduced!

    It becomes apparent that for many of us the best we can do is exercise, eat whole foods and listen to our bodies.

    • Ryan says

      If all of these low carb diets are so great why is it that the cultures who eat the most unprocessed whole food sources of carbohydrates, not animal protein, and not fat, live the longest and have the least of metabolic diseases? It’s not the carbs that are causing metabolic diseases. It’s a combination of too much sugar, too much refined starch (flour), too much fat, too many animal products, too much oxidized vegetable oil, and not enough unprocessed whole food, mostly plant based foods. But unfortunately that’s not sexy enough for the majority of the public, so sensible advice doesn’t sell very well. What does sell is the great conspiracy, the notion that someone or something else is to blame. It’s the governments fault, it’s the USDA’s fault, it’s fructose, it’s wheat, or gluten. When people start taking responsibility for their own health and start spending more time in the produce section rather than more time debating on which fat-free, low carb snackwell cookie to purchase, they’ll start to see their health improve.

      • Tom boyer says

        Ryan’s comments kind of exemplify some of the confusion and misinformation out there. Example: “It’s not the carbs, it’s the sugar and refined starch …” Well what are sugar and refined starch exactly?

        In fact low-carb (and all its forms, such as Paleo and Atkins and Perfect Health and LCHF) have caught on like wildfire, despite almost total hostility from the health establishment, because THEY WORK.

        In fact focusing on limiting carb consumption is very much backed by science (at least 18 peer-reviewed studies have now validated low carb as a weight loss strategy). It is much more scientifically sound than sprouted grains or “raw foods” or “whole foods” or organic vegetables or any one of the hundreds of other diets out there.

        There really should be no debate about what to do if you’re overweight. Cutting the carbs will result in weight loss in an overwhelming percentage of people.

        The only thing that is problematic is that low carb is hard to do in a society where cheap tasty carb junk food is everywhere. You can’t work in an office without people bringing in doughnuts, cookies, candy etc.

        Imagine what it was like when scientists started to realize how toxic cigarette smoke was, but it was so hard to quit smoking because everybody in your office was bringing in cigarettes and smoking them in front of you! Low carb is hard to do in a world full of junk food. That’s the main reason it doesn’t work for so many people.

        What is interesting about LCHF scientifically is no longer weight loss — that question should be regarded as settled. What is interesting is LCHF’s potential for alleviating other illnesses from bowel disorders to brain disorders, autoimmune problems and potentially some cancers.

        That’s why Perlmutter’s book is significant — he represents the next wave of thinking about LCHF — applications to neurology. He’s an eminent neurologist with a very respected practice where he’s been working with diet therapies for decades — and he is absolutely, passionately persuaded that limiting carbohydrates is good for your brain.

        People may have all kinds of reasons to be hostile to low-carb — the official government diet recommendations, based on some bad science from the 1960s, are still pushing a high-carb low-fat diet. But anybody who is really paying attention to the research knows that is wrong.

        Some of the hostility is also coming from the vegan/animal rights community worried that low-carb means more meat. Be wary of these people because they are not interested in your best health — they are trying to protect animals, and that is a conflict of interest.

        Whether or not we should kill animals for food should be a separate question from what is the best diet for maintaining weight or maintaining your brain in good condition. Both are questions worth asking, but they should not be intertwined.

        If someone is overweight and/or pre-diabetic or exhibiting other symptoms of metabolic disorder, then they should be looking at low carb. That is just the truth. If they’re vegetarian/vegan, then find vegetarian/vegan ways to do LCHF — and they do exist.

        The other question that is open scientifically is what low-carb looks like. Is it 20 grams a day or 50 or 100? And the answer to that one is clearly going to be different for every person — based on size, exercise habits, genetic makeup etc. Everybody has a tolerance for carbohydrates and the only way to find out what it is is to vary carb consumption and find the carbohydrate level at which you are weight-stable. Some people can eat 2,000 carb calories a day and maintain weight but most of us cannot.

      • beaker says

        Ryan, it’s always frustrating when people refuse to help themselves and put everything in the too hard basket (just give me a pill). My 76yr old father-in-law has severe reflux and Gerd. I have tried talking to him about things he needs to do in order to alleviate it. I got nowhere. For breakfast he has sausages, bacon, eggs and coffee, more coffee throughout the day, and in the evening he has several soda waters with whiskey along with more reflux triggering foods. He’s made no effort to change anything, instead he has been put on PPI’s. So now he’s tried to mask the problem which will lead to further gut dysbiosis (he already has signs of IBS from being on the PPIs). ALl of this could be avoided but his mindset is that he went to a doctor and the pills will fix him up. Typical.

        • Tom Boyer says

          Beaker, I have a lot of experience with reflux firsthand and in my family. This is another area where people are getting terrible advice from their family doctors.

          People are prescribed Prilosec without any warning of the serious dangers of taking it for extended periods. And they’re told to avoid greasy/salty/acid foods

          The one thing they are almost never told is the thing that will work — cut down on wheat, corn and sugar. Dr. Eric Westman of Duke University, who oversees the Atkins Foundation, says reflux symptoms typically cease completely within a few days of starting a low-carb regimen, and that was certainly my experience. It’s magical. Gerd just plain goes away. That by itself should be enough to get a lot of people to try low-carb.

          If I eat badly (I typically fall off the wagon during holiday feast times), it comes back. If I eat a plate of spaghetti or a pizza, GERD often returns. But then it ceases the day I get back on the wagon and avoid sugar and grains. it’s like magic.

          Otherwise we don’t follow any of the conventional advice. We drink a lot of coffee, and our breakfast is typically eggs and some combination bacon, vegetables, fish, cheese. We don’t avoid acid, salt, grease, spicy foods. We do avoid wheat and sugar. Heartburn is basically nonexistent for us.

      • Philomina says

        I agree with you. I come from a tribe and I know other tribes in Cameroon that eat the most unprocessed whole food sources of carbohydrates, corn/maize, cocoyam, plantains etc. very little animal protein and fat, mostly red palm oil locally processed. For my life in my village I only saw three truly obese individuals in the village and I would say little metabolic diseases. That was then, things have probably changed with the infiltration of processed food products and so on. “It’s not the carbs that are causing metabolic diseases. It’s a combination of all what is added to the carbs in the process of processing and preparation. The wheat itself is adulterated. So what is the source of carbs that is being debated here that needs to be eaten in less quantity. It seems as if we have totally ignore the principle of bio individuality.

  96. Mary says

    This argument that just because an intervention can be used to treat a problem doesn’t necessarily mean it caused the problem, or can be used to prevent the problem, is really disingenuous.

    Think about it with respect to cancer. Ketogenic diets are being used to treat cancer with good outcomes. According to the argument above, this is not enough to suggest that someone should restrict carbs if they really want to prevent cancers from developing. But think about the mechanism underlying the treatment of existing cancers with keto diets: the lack of glucose spikes starves the cancer of the only fuel it can use. So it stands to reason that eliminating glucose spikes would prevent cancers from developing in the first place. Is there actually any scientific EVIDENCE that this is true? Not yet, but that doesn’t mean that people with lots of cancer in their families should buy the argument that keto diets shouldn’t be used to prevent cancer.

    As for Alzheimer’s, although the mechanism may be a bit more complex, I think the argument for prevention is even stronger, given that there are no effective treatments available!

    • Tom boyer says

      Mary: This argument that just because an intervention can be used to treat a problem doesn’t necessarily mean it caused the problem, or can be used to prevent the problem, is really disingenuous.
      Yes exactly. It is as disingenuous as the tobacco companies maintaining, as they did for decades, that it was just a coincidence that people’s lung cancer rates went down when they gave up cigarettes.

      Low carb is grounded in some excellent science over the last 20 years. The question of effectiveness and safety of low-carb diets has been SETTLED folks. It’s almost a waste of time to continue to debate it.

      It is not surprising that Coke and Pepsi and ConAgra are not happy about this science.

      But it is disappointing that groups like the American Heart Association and the American Dietetic Association, whose mission should be to promote good health, are so closely allied with (and receive so much money from) the processed food industry that they are pretty much still endorsing a high-carbohydrate lifestyle that is without a doubt killing millions of Americans. We deserve better.

  97. PC says

    Perhaps it’s what carb-rich foods contain that is truly important – the antioxidants. Maybe that’s why we have a taste for them? I often get cravings for something “fruity” after eating protein, which can be alleviated by taking vitamin C powder.

  98. says

    First of all, half the reason I read these posts is to hear what Chris says and the other half is the comments. I always learn so much from the comments. I subscribed to comments on this post, so it has been on my mind a lot as I get the email alerts. I really think people could argue back and forth on the benefits of keto, VLC and moderate carb diets all day long. There is so much grey area- even for people who are very well read on the topic. Studies are never perfect and everyone has different life experience. This is fine. I don’t think it is a black and white issue.

    What is black and white, is the logical fallacy that Chris Kresser points out in this article. Kresser is not dismissing Perlmutter’s work with Alzheimer’s patients, he is merely saying that correlation does not equal causation. Don’t confuse therapeutic effect with causation. Perlmutter is recommending a VLC diet as a preventative. The problem with this approach is that it doesn’t account for confounding factors. Here is an excerpt from wiki on logical fallacies…

    “The logical fallacy can be expressed as follows:
    A occurs in correlation with B.
    Therefore, A causes B.
    In this type of logical fallacy, one makes a premature conclusion about causality after observing only a correlation between two or more factors. Generally, if one factor (A) is observed to only be correlated with another factor (B), it is sometimes taken for granted that A is causing B, even when no evidence supports it. This is a logical fallacy because there are at least five possibilities:
    A may be the cause of B.
    B may be the cause of A.
    some unknown third factor C may actually be the cause of both A and B.
    there may be a combination of the above three relationships. For example, B may be the cause of A at the same time as A is the cause of B (contradicting that the only relationship between A and B is that A causes B). This describes a self-reinforcing system.
    the “relationship” is a coincidence or so complex or indirect that it is more effectively called a coincidence (i.e. two events occurring at the same time that have no direct relationship to each other besides the fact that they are occurring at the same time). A larger sample size helps to reduce the chance of a coincidence, unless there is a systematic error in the experiment.
    In other words, there can be no conclusion made regarding the existence or the direction of a cause-and-effect relationship only from the fact that A and B are correlated. Determining whether there is an actual cause-and-effect relationship requires further investigation, even when the relationship between A and B is statistically significant, a large effect size is observed, or a large part of the variance is explained.”

    So until there is further evidence to support Perlmutter’s argument, it is dangerous to recommend that everyone go VLC. And for those of you who think that carbohydrates are unnecessary, I ask you this…

    Why does human breastmilk contain approximately 40% carbohydrate? Why would babies, whose brains are developing faster in infancy than at any other point in their life, thrive on a 40% carbohydrate diet? Carbs don’t seem so unnecessary when you look at it from this perspective.

    I think most of us who read this blog try to look to the root of the issue. And I think pointing fingers at carbohydrates is a gross oversimplification. I suspect the root problem is gut dysbiosis.

    I’m curious to hear what others think….

    • Bruce Wilson says

      First, a food that contains 40% carbohydrates, contains 60% protein and fats. So yes, the baby is being fed a food that is 40% carbohydrates because it needs to grow. So the point is not that we don’t need carbohydrates (we do obviously) but that an adult, an individual that is more concerned with maintenance rather than growth, does not eat to eat carbs at every meal, nor do they need to eat them every day. People such as the Inuit are proof of this. Since we are aware of at least two metabolic pathways: carbs to fats, and fats to carbs, its clear that we can consume either. What amazes me, is that this is common knowledge in the A&P fields, but seems virtually unknown in the dietary field. If I can survive on a low fat diet, surely I can survive on a low carb one as well.

      • Megan Oien says

        I wholeheartedly agree that people can thrive on vastly different macronutrient ratios. That was my point. Carbs are not poison and neither is fat.
        I understand that babies have a higher carbohydrate requirement for growth, but my question is: how can something so necessary for a baby, become poison to an adult? The adult may not require 40%, but certainly carbs cannot turn to poison at some point in our development.
        That problem is not the carbs, but the gut dysbiosis that people who eat modern foods have. Fix the gut, you fix the problem. I tolerate carbs very well. I do not crave them anymore than I crave fat and protein.

        • Bruce Wilson says

          I am not sure if anyone really believes that carbs are poison. Its simply that sugars and starches (and to a lesser extent sugar alcohols) are much more easily available today than to people even a hundred years ago. and thus easy to over consume to our detriment. Over much of our history as human beings, the only quick source of sugars was found in raw honey. Otherwise sugars were to be found in fruits and vegetables, something clearly seasonal. In the temperate regions, carbs would be scarce in the Winter, and plentiful in the late Spring and early Summer. Fruits of course, such as wild berries, would be consumed whole.

          It should be noted that in the entire course of agriculture, the motive behind developing cultivars was to increase size, yield, and sugar content of the plants. Most of what we grow has no wild counterpart, instead they are hybrids of hybrids, with a much higher sugar content than in any wild plant. Ever seen a wild strawberry and compare it to the strawberries in the supermarket?

          Anthropologists (yes, I was one for a short while), noted two driving appetites in Hunter Gather and primitive agriculturalists, and that is for starches/sugars and for fats. Protein, of course was desired, but not as esteemed as the other two. Fat was so esteemed it was not usual to find people simply scooping up the fat from a freshly slaughtered bull and eating it in vast quantities. After fat, blood was highly valued, and eaten raw or cooked into dishes, often mixed with fermented milk.

          I remember watching one film in which two African boys from a village came across a wild honeybee colony. They proceeded to pull big chunks of honey comb out dripping with honey, and proceeded to eat the entire thing; wax, honey, and larvae. That, I suppose is the reality of the human diet, and something the average Western surburbanite will probably never grasp.

    • Bruce Wilson says

      The problem with bringing up this particular logical “fallacy” is that there may be no way to definitely prove most things, given that level of stringent “proof”. The argument you just gave was the exact argument the tobacco industry used to deny the involvement of cigarette smoking in lung cancer deaths.

      So the counter argument runs thus. Whenever A is found, B is found as well. We are not sure of causality, but it doesn’t seem to matter, because there seems to be no exception to this occurrence. Now we add in many more factors. Whenever A is found, we find B, C, D, and F.

      This is what circumstantial evidence is: evidence based on circumstances. So suppose you walk into a room and see a dead body. Also in this room is your good neighbor, Frank. Did Frank commit murder or was an innocent bystander? Next week you find another dead body. Once again Frank is near the dead body. We are unable to prove with 100% certainty that Frank killed the victim. This goes on several more times. So while we cannot “prove” with 100% certainty that Frank killed anyone, we suspect that Frank has something to do with all these deaths. We don’t know if its intentional killings, unintentional killings, or what. But we at this point have enough circumstantial evidence to warrant a closer look at Frank, or to start avoiding him altogether, or perhaps “quarantining” him.

      The reality is, if we waited for 100% proof of causality, Science would simply not be possible. This is why scientist develop models and create theory to guide their work.

      From what I read of Dr. Perlmutter, he is not making simple errors of logic. He is looking at a preponderance of evidence, some of it circumstantial, and drawing conclusions. Have you actually read his material?

      • newbie says

        @Bruce, there is a good study showing mortality is higher in low carb dieters.


        Low-carbohydrate diets were associated with a significantly higher risk of all-cause mortality.

        What is your take on this?

        • Bruce Wilson says

          The problem with discussions of this sort is that studies are used like proof verses in theological arguments. Each study must be analyzed as to its merits, and then considered along side other studies. All studies must be looked at, including those that seem to give contrary results.

          In light of all this, Science itself has its limitations (an excellent book along these lines is “Limitations of Science” by Sullivan. Science that uses studies use the Socratic Method, which was originally designed, not to discover “truth” but rather to show errors in logic, or to show the futility of using logic to discover “truth”. Hence, to show us the limitations of Science, not to discover the operating principles of Nature.

          The problem with all studies is that they can be designed, whether consciously or unconsciously, to confirm or discredit any particular premise. One thing to keep in mind is that large studies are quite expensive, so where is the money coming from? So who would benefit if we ate more carbs? Or if we ate more protein?

          So its rather pointless to talk about “good studies”. Which study is it, and can the general public access the write up and data?

          For example, information concerning the Kitava in the Pacific Islands mentioned in this article are not to found anywhere, except for a single researcher. A Swedish doctor lived among these people several decades ago, and there is not one other source concerning these people and their dietary habits. For Chris to cite them shows how weak his argument his. In addition, this doctor did not actually perform any physical exams, he simply asked people if they displayed symptoms of heart disease, etc, or if they knew anyone else who did. So without any objective evidence, this testimony is subjective. In addition, according to source, these people actually ate a fair amount of coconut fat, and smoked a fair deal. Oh yea, they also were field laborers, working at hard physical labor for 8 hours. They also were quite small. And so on. You see, details matter. There are probably more important details, but we don’t know them, because we don’t have any other researcher to cite. Just the one, with questionable research methods.

  99. Dick Hoskins says

    Dr David Perlmutter’s name does not appear in Medline, the abstracting service for all medical journals at the National Library of Medicine. There is a D Perlmutter who has done liver work in the past. Also I could not find any studies concerning gluten free, low carb diets as a significant protective factor for dementia. As all scientists know the plural of anecdote is not data. Clearly Perlmutter has made a bundle off his books but the science is thin or likely non-existent. There may be some biological plausibility but plausibility is not fact and most hypotheses evaporate in the face of a well designed study. Very few survive real scrutiny. This may be no different or it could be actually true, but Perlmutter clearly does not have enough, maybe any evidence that what he is promoting is true. Buyer beware.

    • Marc Strumpf says

      I found this in Forbes:

      A Mayo Clinic study published earlier this year in the Journal of Alzheimer’s Disease found that people 70 and older with a high-carbohydrate diet face a risk of developing mild cognitive impairment 3.6 times higher than those who follow low-carb regimens. Those with the diets highest in sugar did not fare much better. However, subjects with the diets highest in fat were 42% less likely to face cognitive impairment than the participants whose diets were lowest in fat.

      Further research published in the New England Journal of Medicine in August showed that people with even mildly elevated levels of blood sugar — too low to register as a Type 2 diabetes risk — still had a significantly higher risk of developing dementia.

    • Bruce Wilson says

      “Well designed study”. This was the game my Anthropology professors loved to play. You see, they didn’t believe homo sapiens set foot in North America before 12,000 years. They could debunk any archeological site that was dated before 12,000 years. They would go through the evidence with a fine tooth comb and find fault with how the evidence was prepared, stored, interpreted, etc. They had a whole range of semantic arguments and such to knock down any student who dared expressed the opinion that Native Americans may have been in the Americas for 50,000 to 100,000 years. Nothing could shake them in their position.

      So I did find a study at NIM thru Medline, but hey, its obviously not a “well designed study” meeting your high standards.

  100. Lou says

    I have type 2 diabetes (along with 18 million other Americans that have been diagnosed) We’ve done it to ourselves (or the food industry in their greed for profit) with fast food, sugar, salt, fat and food that has little or zero nutrient value. We didn’t eat this way fifty years ago. I know Dr. Perlmutter has his critics, but I’m not one of them. We’re facing serious health epidemics in this country. If we don’t make some changes in the way we eat we’ll cripple our health care system and have a disaster that may be impossible to recover from.

  101. Craig tindale says

    I am sorry i was expecting a more thoughtful article and debate. Folks talk about a lack of peer reviewed science with respect to gluten and I wonder if folks have really looked for it ( there is a mountain out there ) . Start with Prof Michael Marsh (Oxford) , Alessio Fasano, Adj Prof Umberto Volta, Aristo Vojdani, Prof. Marios Hadjivassiliou, Prof. Yehuda Shoenfeld just to start ( I can think of another 5 at least ) all of them have over 150 peer reviewed papers each.

    • Tom Boyer says

      +1 I understand there is way too much science to read, but it is unfortunate that docs tend to have that mindset “If I haven’t read it, it must be quackery.”

      Amazingly, in this day and age with information (including medical journal abstracts) so widely available and easy to locate, sometimes patients are better informed than their docs, who are still stuck in the scientific paradigms that they were taught in medical school 20 years ago (paradigms which in turn were based on science done 20 years before that). It is only because of this terrible inertia that doctors are still pushing the low-fat high-carb “healthy grains and fruits” diet that is doing so much harm.

      At least Chris Kesser provides this forum where alternate points of view are tolerated!

  102. Elisabeth says

    Lots of commenters have talked about the fact that today’s wheat is totally different from ancient varieties. Does anyone know if these ancient varieties are being grown anywhere? I know Kamut is toted as an ancient wheat, and also spelt, but how about other varieties?

    BTW, I remember reading somewhere, probably in Atkins, that the ancient Egyptians, who presumably ate ancient varieties of wheat, had atherosclerosis.

  103. says

    The whole debate about carbs being unhealthy for brain seems baseless on first look because if we see many tribes prevailing in several parts of the world, we see that they mostly consume high carbs but there are no instances of such brain related diseases found for them.

    Also, the ability to digest carbs depends on our own physical activity as people who do more of physical work can digest carbs easily but people who have mostly “sitting jobs” may see ill effects of carbs.

  104. Lee says

    I did read the book and I totally agree with Dr. Perlmutter. I do not agree with you. First of all I believe this book was written for people who are NOT sick. Dr. Perlmutter states very clearly, once we contract some of the chronic diseases which plague people eating a North American diet there is no cure…only management from then on. However, following his dietary recommendations gives people the change to AVOID the chronic conditions which can rob us of our health.
    Furthermore, it seems Dr. Perlmutter is targeting people who do not and probably never lived in places like Tanzania or if they did, it was thousands of years ago. He is right when he says humans had access to fruits in season. Those populations ate fruits like berries which we now know are very high in antioxidants and take note these are listed as preferable foods in his book.
    After reading your article there are many other comments I don’t agree with after reading the book twice. I wonder if you read it or just perused it?

  105. Eden says

    I realize that this is the sort of comment that scientists will scoff at, because I hold no science degree, and my experience is anecdotal–but the grain-brain diet makes sense to me. I remember a few years ago trying to combat my depression. Depression runs in my family, as does alcoholism, hypoglycemia and diabetes. And I remembered hearing once that hypoglycemia is often misdiagnosed as depression (and even schizophrenia)–and I start to think about how all of these things–the alcoholism, the depression, the blood sugar problems were probably all the same thing. So I did some research and discovered that most alcoholics have blood sugar problems (makes sense since alcohol converts to sugar), and of course they also frequently suffer from depression. It was also a curious thing to me that in times of depression, I not only wanted to binge, but wanted to binge on carbohydrates specifically (where you’ll find most of the gluten–it seems to me these things are connected). So I tried going largely carb free, excepting salads or fruit, but nothing overflowing with carbs. And yes, it helped my depression tremendously. Not only that, but it made me far less premenstrual. Not only that, but it also took away my cramps on my period (which have always been incredibly severe). And yes, it also made me lose weight (though not to a scary degree. It seems to me that anything that can change your brain in the short term can also change your brain in the long term. And since diabetes is linked to dementia (and that is true), this seems to me to be true. It makes a lot more sense than the diet we currently use. And as they say, the simplest explanation is often the best. Now, all of that being said, I’m currently not on a low carb (or low gluten or low sugar) diet (and I’m also currently depressed). Why? Because I fell off the wagon. Because I like pasta and bread. And I think that may be why we resist these sorts of claims–because we like our bread, we like our beer, we like our pasta and we don’t want to give it up. Do I think that this is something that should be recommended to everyone or just people with blood sugar problems? I don’t know. I don’t think it would necessarily hurt, but I know for me, this morning I had eggs for breakfast, and I think I might just make some fish for lunch and get back on the wagon. Because I’m depressed. And I KNOW from my own experience that grain doesn’t help that–it fuels it. Considering how many people are on anti-depressants in this country, I might suspect that more people than we realize should perhaps try eliminating carbohydrates. Perhaps there isn’t enough research done…but I don’t mind volunteering myself as a guinea pig, because it’s clear to me that diet DOES affect brain function (why wouldn’t it?) and that it’s worth a shot. If everyone buys this book and the diabetes rate (and thus the dementia rate) goes down? Then we’ll have our research. If it doesn’t? I doubt it will go up much higher than our current system.

  106. maria says

    Eden: Your comments suggest a question I have, namely, I wonder if some people are pre-disposed toward problems with blood sugar. I have been on a Paleo diet for some time, with excellent results in terms of how I feel. So I was surprised to find my blood sugar is fairly high, high enough to be alarmed about, after having read GRAINBRAIN. I have experimented with cutting back on carbs (fruit, sweet potato) and feel my mind is clearer. My mother spent the last 15 years of her life with dementia, a warning bell for me.

    • Bruce Wilson says

      “However, this analysis is based on limited observational studies and large-scale trials on the complex interactions between low-carbohydrate diets and long-term outcomes are needed.”

      do you understand the word “limited”? It means this study has limited value.

  107. Judie says

    Chris, there was a question posted earlier regarding hair loss on a low carb diet which I haven’t seen answered and the answer would really be helpful to me.
    I lost about half my hair several years ago while on a low carb diet. I want to do low carb again but need to what to do to prevent the hair loss.

    • Patti says

      Hair loss is a symptom of low thyroid, which, in some people, can be caused by low carb eating. (It happened to me.) If you want to avoid hair loss, avoid low carb eating. Keep your carbs at 100 grams per day or possibly higher if needed to avoid hair loss. That is still much lower in carbs than the SAD. Every person is different so you have to see what works for YOU.

  108. Ann Coleman says

    I so appreciate the information from the books; Grain Brain, Wheat Belly and Paleo Diet. I have read the first two and I’m learning more about the Paleo approach. It’s about time we all get on board. If your blood sugars rise from fruits, grains, potatoes and other carbs, the results over time can damage all of the cells in your body including the brain. Everyone has different metabolisms and each have a varied amount of insulin the body requires. Unless you are already diabetic (Type 1) like me. I know for a fact that I cannot eat fruit without cause unless I’m exercising. Even carrots, onions and tomatoes affect my blood sugars. Grain Brain, Wheat Belly and Dr. Richard Bernstein all want no elevation or spike in your blood sugar. So, why do some other cultures tolerate a high carbohydrate diet without illness? I would like more information on specifically the types of fruit, their sweetness for example and the level of activity these people have on a daily basis. If I was a marathon runner or hunting, gathering my food all day, I would be able to burn the extra glucose without harm. But, with a more sedentary lifestyle, these extra carbs- in any form are mere poison.

    • Philomina says

      I come from a culture where carbohydrates (corn, cassava, cocoyam, plantains, Irish and sweat potatoes, all kinds of yams etc.) are staples. Of course, theses are consumed with all kinds of green leafy vegetables and oilseeds (peanuts, egusi, pumpkin seeds, and other seeds), beans, and little meat and/or fish in some areas. Carbs makes up about 80% to 90% of their meals.

      I think it is important to be specific about the types and sources of the carbs and not just say low carbs. We now know that the wheat we have now has been adulterated and reason not to eat it. It is also important to be specific about the types and sources of the high fats, now the GMO is spreading. Coconut oil is one of the good fats, but can you imagine if the coconut tree is genetically modified or the plantation is spread with GMO insecticides? I believe there is much more involved here than just low carbs high fat or low carbs. Human being is more complicated than that.

      I believe in the principle of bio-individuality. No one-size fits-all anything. The culture I come from seems to tolerate very high carbs well.

      Even with the Paleo diet, Kris is now coming up with “your personal paleo.” I might not have quote him right but it is something in that line. What does that tell us?

  109. Chic says

    Yeah Judie, seems there is a lot of talk on other boards more Adkins/weight loss oriented that have chat about lc and hair loss. The idea posed is that this diet creates such a hormonal shift as to jolt the hair into telegen phase. Eades addresses it on his blog. I ended up with horrific hair shedding from going lchf when my iron intake become greatly enhanced. Haven’t had the chance to dig in and research more about the increased absorption of minerals eating high fat, but it exists. There is also the angle of lower carb often meaning less fiber intake to bind up minerals. I can say like many other with the lc hair shedding, Never felt better eating lchf, hair just went weird!

    Did your hair loss clear up when you added carbs? Could be some people’s hair likes more carbs-?

    • Judie says

      Thank you for responding. Yes, my hair did grow back in after stopping lc for a while. I will check out your suggestions. Thanks.

  110. beaker says

    There is a lot more here than meets the eye. It’s now becoming obvious that our gut biome is responsible for health and longevity. For example people with chronic illness have different gut biomes than healthy individuals. A study just the other day showed the gut bacteria b.fragilis creates a compound that instructs our guts immune system to not attack gut tissue.. and the conclusions were rats lacking b.fragilis developed inflammatory bowel disease. They are finding those with diabetes or on the way to diabetes have different gut flora. Gut bacteria is now linked to RArthritis, those with RA have a specific bacteria overgrowth that non RA folks do not have. We also now know that what we eat greatly affects our gut biome. The biome of a meat eater if vastly different to a Vegan, etc. Gut bacteria now implicated in metabolism. 100′s of issues are now being linked to our microbiome. I am beginning to think the biome determines how well we tolerate and process carbs. I have no issue with moderate carbs, am fit and have bloodwork to indicate this. Suppose I started eating JUST carbs and sugar and dead food. This then changes my gut biome and the beneficial bacteria that used to keep me in check die out THEN causing diabetes or brain disorders. I suspect in the not too distant future we will comprehend that it’s not what we eat it’s what our biome eats that determines our human outcome. In other words I seem 100% fine with moderate carbs but I exercise and I also eat a great deal of vegetables etc. Also, exercise and stress affect the biome. Look for a shift from “You are what you eat” to “You are what your biome eats”. As this proves to be the case, specific colonizing gut bacteria can be supplemented in pill form to correct 100′s of illnesses.

  111. Ticia Grant says

    Actually in this case, Dr. Perlmutter proved that it is not just correlation with wheat and starches being linked to DEVELOPING neurological diseases… it is causality! The experiment he conducted with the mice/ rats shows that the ones who were fed grains and starches developed tumors, had slower cognitive responses and died sooner, than those which were fed no grains, over their lifetime of about 2 years.

    How can you make statements contradicting this convincing evidence?

  112. Colin says

    Ok, so could someone authoritative just give me some general advice re how to eat?

    I don’t have enough either time or money or geographic opportunity to obsess endlessly over food choices. I also distrust anything too faddish. Many persons in my family have lived fairly long, reasonably healthy lives, eating some combos of health + junk, though I worry that the modern world is increasingly unhealthy (less in terms of toxic environments, which anti-pollution laws may have made better, but more wrt nutritional values from depleted soils as well as modern pesticides).

    I have tried to eat moderately healthy (as conventionally defined in the USA in the late 20th/21st century), but I think I may have been eating all my life extremely unhealthily.

    Yes, I eat junk food (more in the past few years due to loss of willpower stemming from being overwhelmed by too many exogenous problems, including some health ones – though these were all orthopedic injuries affecting my ability to exercise, which I like). But I always tried to “balance” the junk with lots of “health” foods: tons of fruits (!), whole grains (which I also eat because cereals are cheap – and what else can you eat at breakfast besides fruit and cereal and whole grain bread with nut butter?! I don’t have time in the mornings to prepare meat & eggs), some veggies, salads when convenient, fish when possible.

    Anyway, what is a REASONABLE diet (in terms of: ease of preparation or restaurant location, cost, availability, balancing health vs weight loss)?

    I would really appreciate any insights. If fruits are bad (I’ve read so often how good they are!), then I really don’t know what I should be doing.

    • beaker says

      It’s at the point now that it’s become a religious style issue. Each diet has rabid supporters and will foam at the mouth anytime someone speaks negatively of their chosen dietary beliefs. It’s become quite scary. My own belief is that exercise and active lifestyle is key. Eating whole foods, fermented foods, sourdoughs for bread etc. I eat a couple pasture fed eggs a day around 1kilo of mixed vegetables, beans, 1.5-2 cups of home made 24hr yogurt, a couple servings of fruit, etc. If you have no prior health issues, are fit and active, eat only whole foods I think this is on the right track. I feel fantastic and simply can’t believe I am doing 50 wrongs things and feel so phenomenal. But, like I say, according to the frothers I am on the road to hell and early death (with much suffering and pain) -whatever can scare me enough to join their religion.

      • Patti says

        Agree. It’s become a religion.

        Eat real, whole foods. Avoid processed junk. And enjoy! Stress will kill you faster than food!

  113. Tom Boyer says

    “Ok, so could someone authoritative just give me some general advice re how to eat?”

    What a great question and I don’t think anybody should claim to know the definitive answer. Many of the “authorities” are still giving really bad advice (a low-fat high-carb diet as a prescription for obesity?! That’s like recommending that asthma sufferers smoke more cigarettes!)

    The closest thing to a really solid finding that we have right now is that Mediterranean works — it DRAMATICALLY reduces death rate probably from a variety of diseases. But why it works we don’t really know yet.

    Basically, if you’re not overweight and your lipid profile is good, I’d say whatever you’re doing is probably working OK. Whether to follow Perlmutter’s advice and avoid grains is up to you, and probably can’t hurt, but it certainly hasn’t been proven that avoiding wheat will reduce your Alzheimer’s risk — it’s only a very intriguing theory.

    However, I think by now it’s pretty well established that if you’re overweight and or showing signs of metabolic disorder, with high trigliceride levels and a bad LDL to HDL ratio, you need to ignore the Heart Association (and maybe your own doctor) and cut your carbs. Whether to do that really drastically (20 grams) or mildly (100-120 grams) is up to you but you should be increasing the percentage of your diet that is fat, and reducing the percentage that is carbs. Counting carbs is far more important than counting calories, but counting calories is almost certainly a good thing too.

    The rest of it is really still subject to very live debate. Mediterranean clearly produces good outcomes but we don’t know exactly why — is it because it’s low carb, or because it’s low-sugar, or because they don’t snack as much so there’s more time with an empty stomach/low blood sugar — or because they get more fish and olive oil and wine?

    Eating more “Mediterranean” is probably a good approach though, maybe for all those reasons.

    The final thought I’d leave you with — EXPERIMENT ON YOURSELF. What is beautiful about diet is you can make changes and then measure your own outcomes. What is happening with your weight and blood pressure? How does your lipid workup look after 3 months of different eating? How do you feel? How’s your alertness, your need for sleep? If you have reflux, does it get better if you cut down on carbs?

    I think our bodies can give us a lot of data about how various diets work on US and that is a lot better data than the so-called experts. Try some different diets for a few weeks at a time – if you seem to do well on it, it is probably because it is working for you.

    In my personal experience, and to my total surprise, increasing fat in my diet (olive oil, nuts, cheese, butter) has made me thinner and healthier.

    But other people seem to feel great living on an entirely carb diet — banana-strawberrie smoothies, pasta, corn chips, subway sandwiches etc. If that produces good outcomes, fine. But it doesn’t for me and probably most people.

  114. Chris says

    You have missed the point! He advocates eliminating WHEAT! He does NOT argue for eliminating carbs, but reducing them due to the impact they have on blood sugar, insulin, etc., and not consuming WHEAT.

  115. says

    Jeff Volek in Art of low Carb living suggested that 25% need a low fat high carb diet. as Volek is a ketosis kind of guy, it would seem to me that lchf can have no trouble with differing diets based on individual needs.

    I just heard Perlmutter on Fat burning man and he said that his approach was NOT based on meat.

  116. Tom Boyer says

    Patti writes: I don’t know why LCHF advocates have such a hard time believing that many people actually thrive on higher carbs.

    But then she adds: And I am an average sized 52 year old female with no known health problems. I lost over 30 pounds when I went LCHF and I haven’t gained it back since adding quality carbs.

    Patti, I agree with you, what works is what works. If you’re healthy on the diet you’re eating, then that is the most important piece of data.

    I do find curious your comments that LCHF didn’t work when you go on to say you lost 30 pounds on LCHF. That is a lot of weight and dropping that much weight probably improved your risk factors for a lot of things. Your blood lipids are probably better for it, and your insulin sensitivity may be improved — which may be partly why you can handle carbs now without gaining weight.

    By adding carbs back in, you’re actually following what Atkins has preached for 40 years. Once you’ve lost the weight, gradually add back in carbs to the level your body can handle. For some people that’s 50 grams a day, for some it’s 250.

    But 500-600 grams a day, the typical American intake, is a recipe for obesity for most people, which is why the United States is on track to have 100 million obese people fairly soon.

    There are a lot of unanswered questions about healthy diet, but there should be no debate that we have a health crisis in the United States. Obesity completely dwarfs all other healthy problems in our society, and diabetes and Alzheimers (which both track obesity very closely) are going to swamp our medical care system if we don’t do something SOON.

    And right now there are only TWO successful treatments for obesity. One is surgery — stomach staples and stomach bands — and one is LCHF/Paleo/Mediterranean/Atkins — which are all variations on the same thing, carb restriction. They are the only things that have been demonstrated to work in significant numbers of people. Exercise and calorie restriction have simply proven to be ineffective for most people. You HAVE to control your blood sugar, and that means controlling carb intake.

    • Marc says

      What Judi may have gone through when she lost energy is commonly known as the “Atkin’s Flu”. After a lifetime of eating sugar and too many carbs the body takes awhile to adjust to burning ketones rather than sugar ( Glucose).

      Many people feel terrible as their body changes from one fuel source to another. Adding some carbs back in will certainly make you feel better. But..If you can get through this phase you will will come out on the other side with a more efficient, fat burning metabolism.

      Often people need to see to their gut health first and repair their digestion. Probiotics and fermented foods for a few weeks will set you up to tolerate a big change in your diet better.
      And of course some people tolerate carbs better than other people. If you want to or need to add carbs I highly recommend the sweet potato. It is slow burning, low on the glycimic index and full of nutrients.

      • Tom Boyer says

        Marc writes: What Judi may have gone through when she lost energy is commonly known as the “Atkin’s Flu”. After a lifetime of eating sugar and too many carbs the body takes awhile to adjust to burning ketones rather than sugar ( Glucose).


        Yes, for a few days to about a week of eating low carb, people with slightly elevated fasting blood sugar will feel listless when their blood sugar is lower than their bodies are used to. In addition, a person’s blood pressure drops — sometimes quite significantly — with the loss of 3-6 pounds of fluid weight that typically happens when you go low-carb. (A very simple solution is to drink a little salty broth when you feel weak or shaky.) These symptoms are short term though and go away once your body gets used to a lower baseline blood sugar and blood pressure (which are both quite good for you, by the way).

        From the studies that have been done of low-carb and other diets, there really is no statistical evidence of health problems from longer term restriction of carbohydrates. There are lots of carbohydrate defenders who would be all over it, but the evidence isn’t there.

        There is a lot of scaremongering about gut dysbiosis if you stop eating bowls of spaghetti and Cheerio’s but I wouldn’t buy it. If you’re concerned about keeping a good healthy gut flora, you can do that quite well with 20-50 grams of carbs. Eat veggies and nuts and lower-carb starches like sweet potatoes (and dairy! — some of the most important gut bacterial thrive on dairy). You may crave french fries, Doritos, coke, fruit juice, bananas, bagels, ice cream etc… but your gut flora don’t need any of it.

    • Patti says

      Tom, yes, I lost weight on low carb, but after a few months, I started to have very low energy and muscle aches in my legs. I also had dry eyes and dry skin and my weight loss had stalled. Dry eyes are a common symptom of too few carbs because mucous production requires carbohydrates. I learned a lot about low carb dangers from reading the Perfect Health Diet blog. I increased my carbs and began to feel so much better. My energy increased, my leg pains went away and my eyes and skin are no longer dry. And I didn’t gain any weight back. I don’t really count carb grams or anything else because I just eat what I feel like eating, but I include white potatoes, sweet potatoes, white rice, fruit, and occasional properly-prepared legumes and grains (usually oats) regularly into my diet. I would guess that I eat between 150-200 carbs most days. In reality, that IS a low carb diet compared to the SAD. But it is not a VLCD which is what most low carb proponents seem to be advocating. I’ve been eating the increased carbs for over a year now.
      I never said low carb wasn’t effective for losing weight. And for people who have a great deal of weight to lose, it’s probably a good starting point. But I believe most people would lose weight just as effectively by keeping their carbs in a more moderate range of 100 grams per day and they would likely avoid a lot of the low carb dangers that so many people have experienced. I am on a couple of Facebook groups and there are many former low carbers out there dealing with diminished thyroid function and other health problems as a result of keeping their carb counts too low (under 60 grams per day). Not everyone will have problems with it. But I become concerned when very low carb is pushed as the only way to eat healthy. It is NOT healthy for everyone. If it works for you, great. But don’t ignore the message from so many people who have had a different experience.
      I’ve been reading about health and nutrition for about 2 1/2 years now and almost every WOE has people who claim their health improved when they changed to “x” diet. But if you notice, the common factor among all of them is that they cut out the processed garbage. I think THAT is the key. Stick to real, traditional foods.

      • Bruce Wilson says

        Well, white rice is not even close to being a “whole food”. It has been polished to the point that only the starchy kernel remains. Since the bran and fiber have been removed, how could little starch kernels be considered “quality carbs” and a whole food?

  117. Megan Oien says

    I still maintain that recommending a VLC diet as a preventative is irresponsible. Many people experience thyroid and adrenal issues by going too low carb. It is not “Atkins flu” as the body adjusts to fat burning. I have read hundreds of testimonials from people who at first felt great on low carb and then afters months things went wrong as the body could no longer compensate. If you search around a little you will too. I think it’s important to realize, that as Weston A Price documented, humans can thrive on vastly different macro nutrient ratios. Some people feel good on VLC, others don’t. But recommending a one size fits all approach is dangerous.

    • jeffg says

      Megan, my sister is 35, slim, healthy and active. A year ago her nutritionist put her on a VLC diet and she did this for months. Things went horribly wrong, she became very lethargic and tired all the time. Going off the diet and back on carbs helped a little but not much. She went through doctors and specialists and now has to be on thyroid medication. No one in our family has any history of thyroid problems. So not only is it possible VLC can impact you, but the damage could be permanent or long lived. It’s been a real nightmare for her to try to get her life back.

  118. Megan Oien says

    Jeff, Sorry to hear that about your sister. The very same thing happened to me. That is how I came to find testimonial after testimonial from those who experienced it too. I am 34, healthy and active, mother of three. I followed a real foods diet before going on GAPS to heal my gut. My gut healed, which is amazing- I can now eat sourdough w/o breaking out in hives and my digestion is greatly improved. While on GAPS, I went too low carb and suffered thyroid and adrenal issues, hair loss, low libido, low energy, unbelievable fatigue. I went from a healthy 125 to a skeletal 115 (at 5’7″). It was obviously not good for my body. I reincorporated carbs and felt better. It has been almost three years now and I feel great. I always have to be conscious of eating lots of cholesterol and fats. I eat a WAPF Diet for Pregnant and Nursing Mothers and it truly saved me. I really don’t eat a ton of carbs, just let my body tell me what it needs. On a typical day I eat 1 quart of raw milk, a couple pieces of sourdough, 1-2 pieces of fruit and maybe some rice or potatoes at dinner with my meat. I hope she finds what works for her. The fatigue was horrible and made cooking adequately for myself difficult. If she has anyone that can help her cook, I’m sure she would find it helpful.

  119. Tom Boyer says

    There is a little bit of informational fog creeping in here and I just want to respond briefly to a few things.

    1) There really is no real data connecting low-carb diet (even very low carb) to health problems, only anecdotes. Every study done has reinforced that it is quite safe. That said, if you have health issues like thyroid problems obviously you would want to have a doctor involved before you make significant changes to diet. Changing your diet, say, from 15% of calories from fat to 60% is going to affect lots of things – fasting blood sugar, lipid profile, body fat level, and certainly thyroid hormone. Most of those changes, for most people, will be clearly beneficial but your mileage may vary. Eating less carbs will reduce your level of a key thyroid hormone, so if you are already low, it could make you too low. But it would be wrong to say a low-carb diet has been shown to cause thyroid disease. If that were the case, everybody from the American Heart Association to Archer Daniels and Coca-Cola would be shouting it from the rooftops: “Save your thyroid – eat more Doritos, drink more Coke!”

    2) Everybody is on the “real foods” bandwagon, and I feel the same way about getting away from factory/processed foods. But we should always be aware of what is supported by science and what is not. There really isn’t proof that eating “real food” whatever that is will make you healthy. There IS very strong evidence that eating less carbs and more fat, if you are overweight and pointing toward metabolic disorder, will help you control your weight and improve your risk factors. There IS strong evidence that Mediterranean diet is highly beneficial for heart attack risk – though we don’t know why (Mediterranean is relatively low carb high fat but it is also lots of other things). There is NO study that I’m aware of that attempts to measure the health effects of eating “real foods.” I don’t even know how you would do that study. I love Michael Pollan but there are definitely times factory food is better. Just one example — canned tomatoes are of far better quality than the dessicated fresh ones you see at the produce stand in the winter.

    3) People who are not familiar with low-carb, and even some people who are, get confused in the complexity of human metabolism. But really there is a very simple mechanism of the heart of it: Carbs drive blood sugar which drives insulin which drives the storage and retrieval of fat. Reduce your carbs, reduce your blood sugar and you will incrementally store less fat and burn more of it. Increase your carbs, you will burn less fat and store more fat. This is why, to fatten up pigs, they feed them the ultimate high-carb diet — flavored corn meal.

    Eat an 80% carbohydrate diet like a lot of Americans do, and it is VERY difficult to avoid becoming obese. But if you are not overweight eating an 80% carbohydrate diet, I don’t know whether low-carb is going to be beneficial to you.

    My advice is limited to people like me – which is probably 60-75% of the population – we will benefit from reducing carbohydrate consumption to one extent or another and increasing the percentage of calories we get from “healthy” fats. That should be pretty indisputable by now. It hasn’t been established what the right macronutrient levels should be — and it almost certainly varies from person to person, and from one time in a person’s life to another.

    4) A lessening of mucous is certainly a side effect of eating less carbohydrates. The Perfect Health Diet folks (who are well intentioned, and well educated but basically amateurs) make a big deal of lack of mucous as a bad thing. But all they are doing is theorizing. There is no real data to back up what they say. As long as the lack of mucous doesn’t make you uncomfortable, it might actually be a good thing. The counter-argument is made by Perlmutter (who BTW has MUCH better health research credentials than the Perfect Health couple). Perlmutter argues that carbs, and particularly wheat gluten, have an inflammatory effect on the entire body, and that’s why you have more mucous – because your immune system is a permanent state of agitation. So is mucous good for you or is it a sign of inflammation, which gets a lot of bad press these days?

    I consider it an open question. I certainly blow my nose less and I breathe a lot better at night now that we limit our carbs (and btw we are not strict low carb – we indulge in French fries and chocolate and wine popcorn fairly frequently). If you are uncomfortable though and your nasal passages get too dry and irritated, that might be a reason to add back some potatoes as Perfect Health recommends. I have read the Perfect Health book. Perfect Health’s recommendations sound good to me — I like their web site — but a lot of it is very speculative.

    • beaker says

      Lack of mucous in the gut is now irrefutably linked to Inflammatory Bowel Conditions. They actually alleviated IBD by supplementing intestinal mucous. This is headed to be a huge treatment for several varieties of IBD. If VLCD reduces intestinal mucous then this is hugely frightening to say the least.

      • Megan Oien says

        Have you read Gut and Psychology Syndrome by neurologist Natasha Campbell McBride? If not, I think you would find it fascinating. I really do think that the gut is the root of it all. There is so much we don’t know about the microbiome. Anyway, I appreciate reading your constantly returning the discussion back to the gut- that’s probably where it belongs.

    • Megan Oien says

      Let’s get back to basics here. The article argues that Perlmutter recommends a VLC diet for everyone as an effective preventative against neurological disorders. Kresser says Perlmutter is confusing therapetic effect with cause. There is no hard evidence except for one small study done in rats (which I, admittedly, have not looked at). Kresser also says that this one size fits all approach is actually dangerous.

      VLC is a rather new approach and therefore there is no hard clinical evidence as to the long term effects of a VLC diet. There are however hundreds of testimonials from people who went into the diet with a healthy thyroid and came out months later with terrible outcomes. So, Tom, I guess I am confused as to what basis you have for dismissing all these peoples testimonials? Is it simply waiting on some official study? Because we all know that science has its limitations. And studies are notoriously unreliable. How have we become a society that worships expertism to the point of ignoring human experience?
      I don’t think anyone is arguing that VLC diets are bad for everyone. Surely, some people thrive on them- at least in the short term- only time will tell for long term (they may set the stage for other chronic disorders). But, I really think it’s close minded and harmful to dismiss the fact that VLC diets are not the answer for everyone. Do you agree Tom?

      • beaker says

        “Because we all know that science has its limitations. And studies are notoriously unreliable.”

        Why basing huge life decisions on “studies” could get your health into trouble:

        “Based on a review of 53 published papers on cancer, Begley and Ellis discovered that only six of them could be reproduced and confirmed in a clinical setting. And the worst part was that the 53 papers were considered to be “landmark,” which means they are generally recognized as having had a significant impact on cancer research due to presenting some new cancer treatment approach or novel therapy for targeting cancer cells.

        “It looks like the scientific literature is contaminated with a growing number of tainted studies, which may reach 89 percent, the results of which are not reproducible by any means,” writes Eleni Roumeliotou for about the shocking findings. “This means that to an extent, we have based our healthcare and clinical guidelines on fake studies that reported untruthful results in order to accommodate the interests of industrial corporations.”

        • Megan Oien says

          Exactly. Science worship is dangerous. But we are taught from a very young age to trust experts opinions over our own intuition and observation. We are not taught logic in schools, but instead encouraged to trust the experts and regurgitate their opinions. And to become successful in the conventional channels, these experts have to comply with corporate agendas. Money rules all. It even dictates how we view our own bodies and what we should be fueling them with. I think we’d all feel a lot better if we started listening to our bodies and attempting to reason things through ourselves rather than relying on studies and experts.

  120. Tom Boyer says

    But, I really think it’s close minded and harmful to dismiss the fact that VLC diets are not the answer for everyone. Do you agree Tom?


    Absolutely. Carb restriction in some form or another is a very good PROVEN option for people who need to lose weight.
    If you are overweight and showing signs of metabolic disorder (reduced insulin sensitivity, high triglicerides, bad HDL etc.), low carb is something people absolutely should consider. It’s not the only way to get to healthy weight but it might be the most effective way to get there for a lot of people.

    The only other thing that has been proven to work is bariatric surgery, which is of course a big moneymaker for docs and hospitals. Outside of people who need to lose weight (which is half of American adults, including me), I find the arguments for LCHF intriguing but not compelling.

    My only real quarrel was with “I know someone who has thyroid disease after being on a low carb diet” — therefore low carb can cause thyroid disease. People shouldn’t be scared that way.

    There have been lots of good studies now — something like 19 of them — and the contention that carbohydrate restriction is dangerous has been pretty well ruled out. Our bodies are designed to do quite well with minimal carbs and many tribal people did exactly that before the fruits of modern agriculture arrived.

    I would make two other points Megan.

    1) The Atkins foundation — which is probably the most scientifically mainstream of all the low-carb variants — does not really advocate “very” low carb — say, 20 grams a day — as a permanent lifestyle. The Atkins method is to restrict carbs to lose weight, and once you reach a good weight, then gradually add back in carbs to the point that your body can handle them. So everybody knows how many grams they can handle without putting fat back on. That point is going to be different for each person depending on their genetic makeup, exercise level, body type, insulin sensitivity — lots of things.

    2) LCHF for brain health is not scientifically proven. Perlmutter connects the dots of the research in very compelling ways IMHO but there is no study evidence saying that eating less carbs and eating more fat and cholesterol will reduce your risk of Alzheimer’s or benefit your brain or body. Perlmutter is a very physician with a very good clinical and research background IN THIS FIELD but the book is his opinion as an expert. It is not definitive.

    There is of course a lot of pseudoscience out there about diet. I’d stick with what has been scientifically tested over the last 20 years and especially the last 5. The closest thing to a gold standard study was the one released in mid-2013 that showed overwhelmingly positive results for Mediterranean diet as a way to reduce heart attack risk. It was beautifully designed and the results were so striking that they discontinued it early because it wasn’t fair to the subjects on the conventional “American” diet — their death rate was so much higher. That should tell you something. Mediterranean is not “very” low carb but it is lower than the American diet, and it is considerably higher in fat — mainly oil and nuts.

    • Mary says


      Thanks for the info about the Mediterranean diet study you mentioned. Do you have a link by any chance?

      I agree with many of your points. It does seem that all the people screaming about thyroid health are pointing only to anecdotal evidence. You say that there are no studies supporting their claims. I would like to invite the people freaking out about the thyroid connection to please post links to actual studies if they have any. If they don’t, and really are basing this only on anecdotal evidence, I would like to know what the proposed mechanism of action would be. If there is some argument that makes sense as to why lack of carbohydrate would cause thyroid disorder (other than, it happened to my sister, so it could happen to you!), I would like to hear it.

      I also agree with Tom’s point about weight loss. I have not found it easy to follow a low-carb high fat diet by any means, but I seem to gain weight like crazy on anything else. I am now 5 ft tall and coming up on 145 pounds, with a lot of the extra around the middle. I think there are ample studies proving that THAT is unhealthy. The only thing I have found to even maintain my weight without losing is LCHF, but I have been scared off of that by all the screaming about thyroid health and “listening to my body”.
      Unfortunately, my body is screaming for carbs, all kinds of carbs–especially refined carbs–because it REALLY WANTS to get even fatter. So, I should listen to it, and go from overweight to obese???

      Instead of all the scare-mongering, I invite people to share ideas about how thyroid issues can be prevented while doing a LCHF diet. I mean everything has side effects, and I’m thinking that bariatric surgery (the only other proven method for weight loss, according to Tom) has a lot more potential side effects than LCHF. So why aren’t people discussing how to mitigate that potential side effect, rather than throwing the baby out with the bath water?

      • Patti says

        Mary, Paul Jaminet (from the Perfect Health Diet blog) has written several blog posts on the dangers of zero carb diets. I think you will find his arguments compelling. He writes specifically about thyroid in these posts:

        Also, to state that VLCD are safe because there are no studies proving otherwise makes no sense to me. I don’t think there are any verifiable scientific studies that prove jumping from a third story window is harmful, but there is enough anecdotal evidence out there to convince me not to try it. The scores of people coming forward who’ve had problems with VLCD is undeniable.

        If you are craving carbs, it is likely because your body is trying to tell you something. Your body is not out to sabotage you. It is trying to obtain what it needs to function optimally. When I include some quality carbs in my diet, my cravings for junk carbs go away. And I am not the only one to have this experience. It is actually much easier for me to stick to my eating plan when it includes some carbs.

        In the end, each of us must decide for ourselves how we will eat. I’ve read so many convincing “scientific-based” arguments on every side of this issue that I have come to realize the only real way to choose is to weigh all of the evidence I’ve read and go with what seems right, and make adjustments based on how my body responds.

        I wish you all the best in your journey.

        • Mary says


          Thanks for the link re thyroid from the PHD site. I will definitely look at these. I have in fact done the PHD. I felt quite good on it, but I was gaining weight. Part of the problem is that, unlike you, being on moderate carb is what makes me crave more carbs so badly. I have tried again and again and again to do some form of moderate carb, but each time the cravings become so bad that I end up eating way too much high carb food and I gain weight.

          It’s not purely a problem of discipline, because I have had long periods in the past when I was able to maintain very low carb (keto) and I had no cravings for carbs whatsoever. I did have relatively low energy though, and that (along with all the warnings about the dangers of LCHF) has me in search of some other form of eating plan (or some tweak that will improve LCHF for me). Right now I am eating moderate carb (with occasional high carb meals when I give in to the constant cravings). My energy is not that much better, and I am steadily gaining weight!

          You said you thought my carb cravings were trying to tell me I needed more carbs to function optimally, but because I only get the cravings when I am on moderate carb (and giving in to the cravings makes me gain weight), I think my body is trying to tell me it wants to be fat. This is why calls to “just listen to your body” really frustrate me–it’s nice if you can do that and it leads in a healthy direction. For me it really doesn’t.

          I also would like to comment on your idea that the dangers of LC are undeniable given that scores of people are coming forward after having problems with low carb. Have you considered the possibility that MORE scores of people are doing great on low carb, and are therefore quietly going about their business without “coming forward”? I’m not saying that there is no issue, but arguments that rely on faulty reasoning like this are not very helpful.

          On this note, I would like to recommend a book to everyone on this thread: Death by Food Pyramid, by Denise Minger. She goes into great detail about the strengths and weaknesses of dietary studies and gives good advice about how to weight the evidence for individual diet decisions. There is also a section about potential impacts of LC on thyroid, which she says merits further research.

          Personally, pending that further research, I would like to hear about supplements or other measures that people like myself, who can’t seem to lose any weight without doing LCHF, can implement to mitigate any possible affects of LCHF on thyroid or adrenal function and to increase energy and maintainability. Instead, all anybody ever says is “add in more carbs–it worked wonders for me!”

          I am looking forward to the book by Dr. Wahls that is coming out soon (The Wahls Protocol). It’s intended for chronic autoimmune diseases, not weight loss, but I’m still hoping there may be some clues in there to help me!

          • Patti says

            I understand your frustration and I hope you can find something that works for you. We are all different and what works for one doesn’t always work for someone else. I wish you the best.

            On another note…I just started reading Denise Minger’s book and am enjoying it so far.

      • Thomas Bihn says

        Have you ever looked into candida as a possible cause of your cravings for carbs? It may be that you could benefit from consuming more pre and probiotics.

        I think it is one reason that coconut oil eaten raw can help.

        • Mary says

          Thanks for the idea Thomas. I am indeed starting to wonder if I am having problems with candida or some type of bacteria overgrowth. Lately I can’t seem to eat much of anything without getting a very full, uncomfortable feeling. And I seem to get major bloating especially after eating a significant amount of starch. I am going to try and good probiotic and see if that helps!

        • Megan Oien says

          I think that a major part of this discussion that has been ignored is the role of gut flora. Mary, I had unbelievable carb cravings before restoring my gut flora to a healthy place. For me, it all starts with the gut. If you have an overgrowth of Candida or some other sorts of bacteria/yeasts, it will be very hard for you to control your carbohydrate intake.
          Being the daughter of an anesthesiologist, I was given antibiotics frequently for ear infections in my youth and acne in my adolescent years- which led to terrible dysbiosis. There was a time when I could not drive past our local bakery without tasting the bread in my mouth. After going on a gut healing diet, breads no longer have that almost magical power over me.
          The two keys were: restoring my gut flora to a healthy balance, which led to #2…correcting nutrient deficiencies (because with healthy flora, I was now absorbing all the nutrients from my nutrient dense diet). If I maintain a nutrient dense diet, I am completely free of all cravings. I can trust my body now and listen to it.
          I don’t really believe in restrictive diets in the long term. I believe in using diets as a therapeutic tool to get your gut to a place where you don’t need to do long term restriction of an entire macronutrient group. I think the emotional effects of long term restriction (which are immeasureable by studies) have a profound affect on our outlook and overall health. So my goal was to correct the issue at the root with a therapeutic diet (this took about 2 years) and then begin to live without major restriction. I used Gut and Psychology Syndrome Diet by neurologist and nutritionist Natasha Campbell McBride.
          I really think that blaming and restricting carbs is symptom treating. Healing the gut corrects the problem at the root. I encourage you to look into it. It truly is a lasting solution.

  121. Mary says

    I also feel compelled to make a general comment about the article that kicked off this epic thread in light of Denise Minger’s interpretation of the evidence.

    If you go back to the first paragraph of the article above, you will see that Chris’ thesis is that unrefined whole-food carbohydrates do not contribute to modern disease. (If anyone is tempted to come on here and say, “oh no, that’s not what the article was meant to support”, please go back and read the first paragraph of the article).

    One of the arguments is that, compared to primates, humans have many more copies of the gene AMY1, which is essential for breaking down starches. Chris mentions in passing that the number of copies of this gene does vary greatly between human populations, but then sweeps this directly under the rug in the interests of supporting his argument that unrefined whole-food carbohydrates do not contribute to modern disease.

    Denise Minger, on the other hand, discusses this wide variation in AMY1 copies among human populations at length. In people with very low numbers of AMY1 copies, starch spikes glucose even higher than pure glucose (and yes, she cites a study that shows this).

    So, clearly, one’s interpretation of the evidence can clearly be influenced by the argument one is trying to make. Denise is making the point that starches CAN in fact be a big problem for certain people, while Chris is supporting the statement that whole-food starches do not contribute to modern disease (and again, if you don’t think that is what he was trying to argue when he wrote the article, please go back and reread that first paragraph).

    I don’t know about the rest of you, but, in my book, the fact that AMY1, a gene that is essential for processing starch in a healthy manner, is SO variable among humans (from 1 copy to like 8) supports the contention that whole-food starches can, and do, contribute to modern disease.

  122. Mary says

    Patti and anyone else interested,

    I have started to look at the first link provided by Patti from the PHD site. It states very clearly at the beginning that the sole conclusion that can be drawn from direct evidence is that a high-PUFA diet is detrimental to thyroid health. It also states specifically that there are no human studies looking at low-PUFA high fat diets in relation to thyroid health.

    It then goes on to detail indirect evidence that may be suggestive. I am going to look into this indirect evidence, but for now I wanted to point out that providing a link specifically stating there is no firm evidence that LCHF in and of itself is detrimental is not a great argument in favour of the “LCHF is dangerous” view, is it?

  123. Tom Boyer says

    Perfect Health Diet is interesting, and Jaminet’s blog has a lot of thoughtful and interesting speculation, but it is mostly speculation. To assert that carbohydrate restriction is somehow harmful to thyroid based on Jaminet’s ideas about mucous — well, that amounts to believing what you want to believe. There are alternate theories that are just as valid IMHO.

    Meanwhile, there are 18 or 19 quality studies over the last 20 years that have shown the effectiveness (and safety) of carb reduction for weight loss — don’t you think if carb control led to thyroid problems that we would have seen it noted in the studies?

    Secondly, the argument is made that if you crave something, your body must need it in some way. That is simply not valid in many cases. Many of the things human beings crave the most — nicotine, caffiene, cocaine, sugar — are clearly not necessary or desirable for human health.

    Sugar is clearly highly addictive. If you, like most Americans, drink a lot of sugary beverages — from fruit juice to drink sugary beverages — if you stop drinking them, you are going to struggle with cravings for a long time. It doesn’t mean those cravings are a good thing.

    The blood sugar/insulin roller coaster is an extremely powerful and destructive thing, but you have no idea how powerful until you get off. Because of our high-carb low-fat diet, Perlmutter argues, so many Americans have permanently elevated insulin levels that our doctors have a distorted idea of what “normal” baseline insulin levels should look like.

    No question, many people who go low-carb have trouble making making it sustainable in the long term. It really does require rethinking the way you buy food, the way you cook, the choices you make at restaurants — everything. I respect that.

    But please don’t draw the conclusion that because some people can’t resist the big bowl of pasta or the baked potato, carb restriction is unhealthy or ineffective. That conclusion does not square with the science at all. (and not that an OCCASIONAL bowl of pasta or potato is a bad thing, it’s just not the basis of a good diet)

    I think there almost no doubt that most Americans would benefit greatly from drastically reducing the amount of carb food they eat — processed and unprocessed. If the government started campaigning about carbs the way it has campaigned about dietary fat and salt, we might begin to make some progress against the obesity epidemic.

    That said, I’m certainly not arguing for a hard core ketogenic diet for everyone. The Atkins philosophy is to restrict carbs, lose weight, and when you get to a healthy weight, put the carbs back in until you are weight stable. There are people out there who advocate for long-term VLC, permanent ketosis, and the science may well validate that approach someday, but that is beyond what the literature says to this point.

    Likewise, if you’re currently maintaining a healthy weight eating what you’re eating, that’s a pretty good indication your body is handling whatever level of carbs you’re throwing at it. You might feel better without that breakfast of a bagel and orange juice, but if your weight and lipid profile are good, there’s certainly nothing definitive out there saying you need to change.

    • Mary says

      Hi Tom. I like your post. I too have the feeling that the PHD site contains a fair amount of speculation. Interesting, yes, but not much there to base a diet decision on for someone who really needs to lose weight and can’t seem to do so without restricting carbs.

      You mentioned that there are 18 to 19 quality studies showing the effectiveness and safety of carb restriction for weight loss. Do you know what the study period was in these studies? Obviously, if the period was only a few months that says nothing about the safety of longer periods of carb restriction.

      • Megan Oien says

        Study length is a great point. My issues didn’t start until a year in.
        And I can most certainly assure you that just because Jaminet mentions PUFAs as the cause of VLC Thyroid issues that was not what caused it in me.
        I still think it’s important not to dismiss testimonials. These stories are powerful. And to say, people fail at VLC because they’re unable to resist their bowls of pasta and Cheerios is incredibly dismissive.

  124. Mary says

    One more general comment for those who are having trouble with whole-food starches despite the PHD and CK seal of approval: people with small intestinal bacteria overgrowth (SIBO) cannot tolerate any starches well. The specific diets that address this are the SCD (specific carbohydrate diet) and the GAPS diet. I’m wondering if these may be why I haven’t been able to tolerate moderate carb that includes “safe starches” without out-of-control cravings.

    • Megan Oien says

      Just saw this! (It’s hard to navigate on my smartphone). You’re on the right track! Correct the problem at the root- your gut. It’s the only lasting solution. I used GAPS Diet. It’s been three years and I have maintained a healthy weight and have zero cravings.

      • Mary says

        Hi Megan,

        Thanks for your input about the gut dysbiosis. Were you actually diagnosed with anything specific, or did you just figure it was that and start following the diet?

        You say you did the GAPS. I have read that the SCD is supposed to be somewhat similar. Do you know what would recommend one over the other?

        For the SCD there is a list online of allowed/disallowed foods, so I guess I will start with that and see how it goes!

        • Megan Oien says

          Hi Mary,
          GAPS is based on SCD. I am not very familiar with SCD, other than what I know of it from GAPS. There were quite a few people on GAPS forums that hadn’t achieved the level of healing that had hoped for in SCD and had moved onto GAPS. I believe GAPS focuses more on the healing properties of broths. The GAPS book is great reading even if you don’t decide to follow the diet. It gave me great insight into digestion and gut health. The website is a little hard to navigate. Hope you find the answers you’re searching for.

          • Mary says

            Hi Megan, thanks for the info re GAPS/SCD. Following the SCD list of allowed foods seems like a simple solution for now and I already do bone broth. If things don’t go well perhaps I can move into GAPS (which I’ve heard is complicated).

            Just realizing that my problem may be difficulty digesting starches is a major step in the right direction. None of the Paleo books I’ve read mention this possibility (nor does the PHD book that I can remember).

            I’m so glad I read Denise Minger’s book, as that is what put me onto this (she doesn’t advocate against starches per se, but discusses the wide variability in the starch-digestion gene AMY1).

            Her book really helped me come to a much-needed attitude adjustment with respect to all the diet claims flying every which way). I am now so OVER reading these diet books–thank you Denise! If anyone else is truly sick of this never-ending debate, get her book! She makes a very limited number of recommendations based on the preponderance of good science, minus the guru-ism and scare mongering!

            • Megan Oien says

              Thanks for the book recommendation. I saw Denise speak at a WAPF conference. And also read her takedown of the China Study. I tend to agree with her from what I know so far.

  125. Tom Boyer says

    Yes I think people should be very careful of claims about “healthy” sugar or “healthy” carbs. Just because it comes from a plant doesn’t mean it’s necessary or good for you. If you guzzle 12 ounces of organic Odwalla juice, it will send your blood sugar and insulin skyrocketing just as effectively as a Sprite, and the fiber and micronutrients in the juice are not beneficial unless you actually need them (and you probably don’t).

    Similarly, while coarse grain and whole grain breads are beautiful and tasty, people should be very wary of claims that they’re all that healthier for you than white bread. First of all, as Michael Pollan discusses in his latest book, “Cooked,” most “whole wheat” flour is simply white flour with some bran additives mixed back in. It’s not anything like real stone ground flour from 200 years ago.

    From the perspective of someone who is sensitive to blood sugar spikes, whole-grain products are no better and may actually be worse. The extra fiber may slow the impact of the grain on blood glucose levels — they smooth the curve out. But that could actually be WORSE for many people because it means there is a more SUSTAINED insulin spike.

    If you are overweight, a sustained insulin spike means a longer period of time when your body is forced to store fat instead of burn fat. So it’s possible that if you’ve got to have 20 grams of carbs, better that they come from a candy bar (which will be processed by your system quickly) than a “whole grain” muffin loaded with “complex carbs.”

    Finally, the argument for the muffin will be that it includes fiber, which is good for you. But study after study has failed to demonstrate any long-term health benefit for fiber. There’s very good theory that fiber should reduce, say, bowel cancer, but every study that has been done to try to prove this has come up empty. Fiber is, at least in the studies that have been done so far, a bust.

  126. says

    Some of you may be intererested in Andreas Eenfeldt. He’s a Swedish doctor who writes that country’s most influential health blog, which unequivocally advocates LCHF. is an English version of the blog, which is also translated into a number of other languages.

    In part because of Eenfeldt, LCHF is more mainstream in Sweden than just about any other place in the world.

    The Swedish Council on Health Technology Assessment, a government panel of experts, last year issued a landmark report saying low carb high fat was the best answer to obesity and diabetes.

    It’s the closest thing to a government endorsement of LCHF — and a reflection of how in this issue, like so many others, the Scandinavians are a few years ahead of the Americans, maybe because their governments are not so dominated by moneyed special interests.

    • Tom Boyer says

      Yes, it’s a pity so many in the vegan/vegeterian community are so militantly anti low-carb because they view low-carb as pro-meat. It really doesn’t need to be. I don’t know why one couldn’t receive the full benefit of low-carb or Mediterranean lifestyle eating only plants. It’s undoubtedly more of a challenge to not rely on grains and starches — but if you’re a vegan, you’re used to challenges.

      Some of the vegetarians are just lazy and want to live on sugar (fruit) and starch (bread and pasta). That for most people is certainly not a recipe for good health.

    • Megan Oien says

      Thanks for the link. My parents switched to low fat vegan a few years ago and I’m always on the hunt for good info to share with them. They eat the polar opposite of what I do and it can be challenging to find middle ground.

  127. beaker says

    Interesting study on plosone:

    “Results and Discussion

    Fermentable dietary fibre decreased weight gain, liver fat, cholesterol and triglyceride content, and changed the formation of SCFAs. The high-fat diet primarily reduced formation of SCFAs but, after a longer experimental period, the formation of propionic and acetic acids recovered. The concentration of succinic acid in the rats increased in high-fat diets with time, indicating harmful effect of high-fat consumption. The dietary fibre partly counteracted these harmful effects and reduced inflammation. Furthermore, the number of Bacteroides was higher with guar gum, while noticeably that of Akkermansia was highest with the fibre-free diet.”

    another high fat study regarding damage to the hypothalamus:

    “The effect of the diet upon the expressions of pro- and anti-apoptotic genes was remarkable. The modulation of 57% of the targets, including proteins involved in both pro- and anti-apoptotic activity, suggests that the fat-rich diet indeed has a damaging effect. As observed in other experimental settings, we suspect that the activation of some anti-apoptotic proteins provides a transient protection against the harmful effects of the diet [21], [22]. However, as shown by distinct methods, ranging from TUNEL to transmission electron microscopy, in spite of the presence of anti-apoptotic activity, apoptosis was significantly increased in the hypothalamus of the HF rats. This was an anatomical- and cell-specific phenomenon since it was detected predominantly in the hypothalamus and affected mostly neurons.”

    I’m not going into details, just making a point that 1,000′s of studies can be cherry picked to promote whatever you want them to. I could do it all day.

  128. Megan Oien says

    I have read the following arguments against carbs in the Paleo world often and they have been echoed here. Just wanted to point out that they are illogical…

    “People don’t need to eat sugars because the body can make all that it requires.”

    Makes no sense. Would you ever use that argument for cholesterol? Our bodies can make it, but we all realize that DIETARY cholesterol is ;important for maintaining many bodily processes. As is DIETARY glucose. You can’t have it both ways

    “You crave carbs. You eat them. The craving goes away just like the smoker’s craving for nicotine.”
    Makes no sense. Would you ever extend this line of thinking to protein or fat cravings? No. Only because of bias- you have deemed fats and proteins “healthy and necessary” and carbs “unhealthy and unnecessary.”

    I will say that people who have a gut flora imbalance do get unnecessary cravings for carbohydrate. On that issue, I agree. I don’t think you can trust your cravings until you get your gut flora in a healthy place. I know I couldn’t. And I do think LCHF can be helpful for those people, but it’s important to acknowledge there are other healthy ways to reset your body. And the only lasting changes come from reseting your body at the gut flora level. To do this, you must not only remove the offending foods (for many- due to Candida overgrowth- this IS carbohydrate), but also incorporate gut healing foods. This is where most LCHF diets fail to give people the lasting changes they seek. Low carb diets keep them tied to carb restriction indefinitely. The problem is the have not altered the gut flora sufficiently and fall victim to intense cravings. Healing the gut is a long term solution.

    Sorry for any typos on my phone.

    • Mary says

      Hi there Megan, burning up your smart phone I see ;-)))

      I think you are right that the gut dysbiosis thing is not on people’s radar as much as it should be. Certainly I was not aware that starches specifically could be at the root of my issues. Now some of the bloating reactions that I’ve had in the past are starting to make sense (like very suddenly 9-months-pregnant-like bloating after eating white rice or white rice crackers, for example).

      However, to be fair to the person who made the comments about carb addiction, the analogy you are making is not truly accurate due to the nature of addiction itself. To be defined as addiction, something that is bad for you has to be done repeatedly/to excess–often in response to uncontrollable cravings that go way beyond satisfying a need–in a way that causes negative repercussions. Many people DO have that sort of relationship with carbs, and the negative repercussions are often very clear (obesity).

      Of course no one is going around saying fat is addictive, but it’s not necessarily because they have a pro-fat bias. Rather, we are not seeing people having this type of dynamic with fat consumption, whereas there are many people who have this type of dynamic with highly refined carbs (I observe this constantly all around me–just look at the grocery carts and the people they are “associated” with the next time you go to the supermarket!).

      Also, I don’t think saying that carbs are addictive precludes the notion that gut dysbiosis may be contributing to the addiction cycle. I think the person who made the remark was commenting on my post, where I was describing craving carbs and eating way too much of them and getting fat. We could say that, possibly due to gut dysbiosis, I am caught in an addictive cycle with carbs. I don’t think the implication was that carbs are inherently addictive, in every context, in any person. That is obviously not the case.

      But look at the wider healthcare context: so many people are obese and diseased, yet talking about the benefits of carb restriction (which IS a proven weight loss method, even if it does have some potential side effects) triggers MAJOR, hysterical backlash in many quarters. I think this is also what prompted the sentiments that were expressed re addition–one wonders if the carb lovers are so hysterical because they are addictively clutching onto their drug of choice!

      I don’t know where you live, but I live in Quebec, where we have a government healthcare system that is completely falling apart under the “weight” of obesity and preventable disease. The wait times even for required surgeries and procedures are way longer than medically acceptable, partly because the system is plugged up with people who are eating themselves sick! So yeah, it’s an issue that touches a cord with me. It’s a “big” deal (pun intended). Yet Perlmutter goes on a popular show and recommends that people eat lowish-carb (60 grams not really being all that low) and people just FREAK out…

    • Bruce Wilson says

      I made the comment I did because your logic was flawed. Cravings are just that, cravings. They can be your body signaling a need, a deficiency, or it may be related to something else. Your logic was flawed because you assume that if your body was craving carbs, therefore you should eat them. That might be so, but it might not. Can you be fair and objective and consider the possibility that there might be other factors? For example, in a personal experience, cravings to chew ice is often related to severe iron anemia. In this case, the craving to chew ice can actually make one sick, as all that ice chills the bodies core temperature. Up the iron intake, and the cravings disappear.

      So while we ask others to be open minded, please follow your own recommendations. I know personally, from my experience, and from others, that the craving for starches/sugars has nothing to do with help, and everything with abusing sugar as mood elevator. This is why Coca-Cola remained popular even when they took the cocaine out.

      Did you know excessive salt can elevate your mood? I had a friend that put copious amounts of salt on his food. In fact, he suffered if couldn’t salt his food. And its no accident that Coca-Cola has a lot of salt. So if someone is craving salt, as i do often, it may because they genuinely need more salt (since it does function as an electrolyte), or it may be that they are feeling a little low, and need the pickup that it gives some people.

  129. Tom Boyer says

    The science on gut flora is bleeding edge right now and probably 75%-80% of what you are reading these days is going to turn out to be at least partially wrong. So it is hard to know what to do with any of that information. We know gut bacteria are beneficial — essential. Beyond that we know very little.

    By contrast, the relationship between carbs, blood sugar, insulin and fat storage is very well established scientifically. The key science was done 60 or 70 years ago. There is no debate about it.

    When you eat carbohydrates, your blood glucose rises, and your your pancreas produces insulin. Insulin opens gateways in your fat cells so that the insulin is stored as fat. That is metabolism 101. When your blood glucose is low, the opposite happens — fat is released from your fat cells and burned for energy.

    The reason people lose weight on low-carb diets — even eating lots of calories — is that they’re keeping their blood glucose low so their body just happily burns their fat.

    The reason Americans are fat is because they eat too many calories but more importantly because they eat primarily carbohydrates and snack a lot (and drink purified sugar products such as sodas and juices). That maintains their blood sugar in a more or less continuous elevated state during every waking hour.

    It makes sense that we are experiencing an epidemic of obesity, diabetes, certain cancers, and alzheimers and it certainly won’t surprise me if it all turns out to be related to our diet and our WAYS of eating (i.e. constant snacking to maintain high blood sugar levels).

    This part of Perlmutter’s reasoning lines up nicely with the research and I bet it will turn out to be true. It seems very logical to me that you could reduce your risk of a whole lot of problems by eating less carbs and eating more fat and protein (which does not impact your blood sugar as much). Basically eat like a diabetic eats and plan your carbs to minimize your impact.

    Genetics, gut flora, exercise level, red wine and fish oil or coconut oil — who knows how much impact any of these things have. But it is well established that if you reduce and control your consumption of carbs, you will keep your blood sugar stable-low and lower blood sugar is probably very good for you in a myriad ways.

    Similarly, this is one of the many reasons exercise is beneficial — it lowers your blood sugar. It’s why not eating between meals may be beneficial. It’s why it may be beneficial to eat a late breakfast (or no breakfast), as they do in many Mediterranean countries — that is keeping your blood sugar at low levels all morning.

  130. Bruce Wilson says

    Exactly. When my wife proposed the family go on a diet, her mother’s immediate reaction was “I don’t want to have to give up my Cokes!” Both my wife and I have experienced this with family and co-workers. Its amazing what people will give up for a diet, but heaven forbid you take away my starches/sugars.

    One thing I picked up from my research is that when people ingest a large amount of carbs, serotonin is also produced. Serotonin helps sedate the nervous system. It occurred to me that when I craved carbs the most, is when I was stressed or bored. Once I made this connection, then came the long process of understanding how to unhook my mind/body from this stress=carb craving and to sedate myself through other means. This lead to higher protein intake, higher fat intake (nuts fill the bill nicely) hydration, and some type of physical workout program (hiking and tai chi).

    So of course if we are craving carbs and then consume carbs, we feel better. A smoker does the same thing with cigarettes. Of course, sometimes we have a protein craving, and we sure feel better when we eat some. But does the craving represent a need, or is it more an emotional/stress stimulas, or something entirely else?

    One weird thing my wife went through some years back was having intense cravings to chew ice. Its was getting so bad that she was actually getting sick by chilling her body. Finally we learned that ice chewing cravings are related to iron anemia. Image that! So she upped her iron intake, and presto her cravings went away. But to follow Megan’s logic, she should have just eaten more ice.

    • Alesea says

      I read that carbs are needed to release serotonin and I know serotonin is not bad.
      When you incresed your protein and fat intake did you experienced some changes in your mood?

      Thank you

      • Marc says

        When you have adequate fat in your diet and are not eating very many carbs, you are signalling your body that all is well.
        For a woman the signal to her body can mean that there is sufficient good food around so it’s okay to bare a child… She may then go looking for you.

        “Oh little pussycat..Where arrrrre yoooou?”

        • Elisabeth says

          At the risk of sounding flippant, I had sudden images of women tearing off their children’s clothes! (bare a child?). But I do want to ask a question. If 60% of the calories of my diet should be fat, how do I get that? I can’t stomach eating spoonfuls of butter, or knocking back coconut oil from the bottle. What is a realistic way to incorporate that amount of fat? Now that I am low carbing, it is more difficult. No bread to spread butter on, no mashed potato oozing with butter and cream. Seriously, what do people do?

          • Marc says

            You burn both the fat you eat and the fat you have stored to equal 60% plus of your energy resources once you are keto adapted..

            Upping your dietary fat intake simply means choosing fattier cuts of meat, especially organ meats. Add butter to everything or add oil or coconut oil or lard. Cook with it, add it.
            Use heavy cream, snack on cream cheese or other high fat cheese. Eat fatty types of fish.

            When you feel like you need more fat, simply add more grass fed butter. If you do have the stomach for straight butter, make bullet proof coffee.
            Make coffee then put in blender along with a generous amount of butter and or coconut oil… Sounds gross but is actually creamy and delicious. Easy way to get your fat intake up.

            Give to your wife or girlfriend, start college fund.

      • Bruce Wilson says

        Yes I did, and do. While sugars satisfy the “sweet tooth”, fats and proteins provide satiety, a feeling of satisfaction, and I no longer experience the spikes and dips. It took two weeks of being on 20 carbs a day to finally shake my last bits of cravings. I tend to have more “desires” now, rather than cravings.

        What I have been experiencing now is more of a more normal “hunger” when I haven’t eaten in a stretch, rather than a severe hypoglycemic state in which I lost my ability to focus and deal with even mild stresses. I would lose my temper, and generally become unable to perform simple tasks until I snacked or ate a decent size meal.

        Of course, all this changes based on my level of physical activity. I can hike all day long with little need to eat. Twice I experienced a severe drop in blood sugar, and I simply rested until I felt better (exercise will drop blood sugar levels). I even feed on some Miner’s Lettuce once to help recover.

        So in short, yes, since my whole life breads and starches held a powerful pull over me (sugar not so much, not sure why), and upping my protein and fat intake, while restricting my carbs, has broken this hold, and as a consequence I have been feeling much better.

  131. beaker says

    There are some new personal diagnostic devices coming out soon. One is like a watch that shines an LED into your skin and then uses a sensor to monitor blood glucose levels and nutrient levels. I’m looking forward to wearing a device like this that monitors 24×7 and collates the data to a smartphone app. I think this will go a long way to everyone being able to customize their diet. Your phone could even alert you to spikes or deficiencies throughout the day. However, we also have a new device in the news an ‘artificial pancreas’ that is the size of a watch, fits in the abdomen, monitors glucose levels and secretes insulin as required. So what will technology do for us? Will it allow people to tailor their diet and maintain healthy glucose levels, or will it allow them to say “woopeee! my new artificial pancreas means I can eat whatever I want!”. Interesting times..

    • beaker says

      Ah, and also new possible nano-technology that will allow people to take insulin pills. If they need no insulin nothing happens, but if blood sugar passes a threshold the pills release insulin.

  132. Tom Byoer says

    Re carb “addiction” — at first glance it doesn’t seem right to compare food addiction to substance addiction (narcotics, alcohol, nicotine, caffeine)

    But when I actually try to draw a line between food and substances, I have trouble.

    1) Your body becomes accustomed to the constant presence of a chemical (alcohol, opium, caffeine). In the case of someone on a primarily carbohydrate diet, that substance is a constantly elevated blood glucose.

    2) When you cut down on the substance, your body has an adjustment period that can be uncomfortable, even painful. When I stop drinking coffee, I get headaches. When an alcoholic stops drinking, he/she can get the DTs.

    Those of us who have cut carbs (Atkins Induction or something similar) know how uncomfortable it is while your body adjusts to lower blood sugar. You get the shakes, the cravings are intense, you can have trouble sleeping, you can faint, you can get headachy, constipated — all kinds of symptoms that are really quite similar to substance abuse withdrawal.

    3) After the adjustment period you feel fine again, and in many ways better than before. After a week without coffee, the withdrawal headaches go away. Similarly, after a few days (or sometimes 7 to 10 days) with little carbs, all the symptoms above subside. Withdrawal for heroin and alcohol is much more severe, which is why those substances are so dangerous. But the withdrawal/adjustment pattern is the same.

    4) The cravings in some ways never go away, and rexposure to the substance causes problems. Does that mean an ex-heroin addict NEEDS heroin? Does it mean someone who used to live on bagels/bananas/Doritos NEEDS those things to elevate their blood sugar. No.

    But the cravings never completely go away. After 5 years of generally avoiding sugar, I still crave sweets — but I no longer them enjoy very much it because it tastes too sweet. Most pastry and desserts are too sugary. However, if someone brings chips or pretzels to my table, I have tremendous difficulty resisting. It gives me a little bit of insight into what it must be like when a crack addict is offered some of that substance.

    Anybody who’s quit smoking knows how hard it is to not want a cigarette when someone else is around you smoking. Carbs present the exactly the same problem because carbs are still tolerated — even encouraged — in a work environment.

    I know it sounds silly, it sounds overly PC, but people should be discouraged from bringing cookies and doughnuts to the office because it is so hard for us “recovering carbaholics” to resist — I would guess eventually carb junk food will be discouraged in an office environment just like cigarettes are now.

    Things that spike your blood sugar are trouble. Office snacks should be low-glycemic-index — vegetables, dips, hummus, nuts, olives, cheese avocados etc.

    When I see people in an office all gathered around a cake, I can’t help thinking — this is what it was like 40 years ago when everybody would gather to enjoy a “smoke break” together. Made it so much harder to quit tobacco.

  133. Tom Boyer says

    Elizabeth asks: If 60% of the calories of my diet should be fat, how do I get that? I can’t stomach eating spoonfuls of butter

    First of all, 60% of calories from fat is a lot. You don’t have to be that radical. How about aim for two thirds of calories from protein and fat and see how you feel on that. If you don’t need to lose weight, one-third of calories from good quality low-glycemic-index carbs is probably great.

    You get there easily and naturally if you just stop avoiding fat. People are so accustomed to doing “low-fat” versions of everything — just quit that. Eat food food with the amount of fat that comes naturally in the food.

    Enjoy nuts, avocados, soft cheese (goat cheese and good mozzeralla and swiss are mainstains for us). Don’t automatically skim all the fat out of your soups and stews. Go ahead and eat dark meat chicken and enjoy oily fish — anchovies, sardines, wild salmon and haddock. If you’re having white meat chicken, cook it with generous olive oil or butter — it will taste so much better.

    Go ahead and enjoy a little steak every couple of weeks. Make sauces from pan drippings, wine and a little cream — a mainstay of French cooking. Eat an egg every day for breakfast — eggs have been vindicated by almost everybody. We eat our egg with a little leftover roasted veggies, and occasionally melt in half a slice of swiss cheese. Or good quality bacon (cooked right, not incinerated!). Or a salmon omelette with a little goat cheese or cream cheese, which is wonderful.

    If you drink milk, just drink whole milk. If you drink your coffee with cream, just use heavy cream instead of that lethal fake “nonfat” creamer (ever read the ingredients list for that dreck?). Buy whole milk mozzarella, stay away from reduced-fat sour cream. Don’t be afraid to melt a little a little butter to your veggies — it will make green veggies taste much better and might help you eat more veggies — which you should be doing if you’re cutting down on carbs.

    You really don’t have to do anything special to add fat to your diet. You just need to discard all the “low-fat” junk foods and food recommendations that have led to this epidemic of obesity in America and eat the level of fat that your grandparents probably ate.

    One final note, which goes without saying. Don’t add fat and continue to eat lots of sugar or refined grain — if you are eating high-glycemic-index carbs, the extra dietary fat may well be harmful.

    But if you’re cutting the carbs, your body will handle the fat well, you won’t put on weight, you’ll feel great and probably your blood lipid profile will improve. LDL will go up but your ratio will be far better and your triglicerides (which are really a better marker than LDL for heart problems) should go down.


    • Tom Boyer says

      And one more though on adding fat to the diet — if you allow natural levels of fat back into your diet, you will almost certainly start to eat smaller portions, and have less of a need to snack, because the food will taste better, you’ll feel more satiated, and you won’t have the blood sugar spikes that cause you to get hungry an hour later.

      One experiment everybody can do that is very telling. One day for breakfast, have a one of those commercially baked “low fat” multigrain banana muffins and a glass of organic fresh-squeezed juice. It will be close to 1000 calories. And then see how long it takes you to get hungry again — chances are, inside of 2 1/2 hours (and sometimes in as little as an hour), you’ll need a snack or an early lunch.

      Then another day for breakfast, have a high-protein, high-fat, low-carb breakfast — an egg, cooked in butter, some bacon or sausage (not cooked dry but with some of its fat), or fish (fish and eggs for breakfast with capers and lemon, cooked in olive oil, is a Mediterranean staple BTW) . Or if you like them, just have a can of sardines for breakfast. Or some veggies with melted swiss or mozzarella or full-fat goat cheese. But — no sugars, no grains, no fruit of any type. And coffee or tea with cream. This breakfast will be well under 500 calories and probably closer to 300. And then see how long it takes you to get hungry. You will probably be amazed by the result.

  134. Megan Oien says

    Tom and Bruce,
    Thank you for your responses. I understand your perspectives more clearly now. I think we probably share more in our approach, than we disagree on. Tom, your Meditteranean approach is far from VLC, so I appreciate that. I am a huge believer in the importance of fat and cholesterol, so you will get no argument there from me. I think low carb can be very helpful for obese people and people heading down the metabolic syndrome route. No argument from me there either. I think the part that bothered me was this idea that carbs are bad for everyone and the only reason people eat them is that they don’t have enough self control. I can honestly say I do NOT crave carbs, but my body runs better if I eat a moderate amount of them. I have also been pregnant and/or nursing for over 6 years now. And that requires a huge hormonal and caloric requirement. For some reason my body does better with this burden when I include carbohydrate. It is in no way the mainstay of my diet. I think carbohydrates definitely can be addicting. They were for me before I healed my gut and I do think many people are not aware of the importance of fermented foods in maintaining gut flora (Kresser is an exception).

    I appreciate carbs for things like:
    Sourdough bread with loads of pastured butter and 3 poached eggs.
    Smoothie- 2 1/2 cups full fat milk kefir, healing 1/4 cup coconut milk, 4 raw egg yolks, with 2-3 cups berries
    Soaked baked oatmeal with lots of butter, egg and cream
    Mashed potatoes with lots of butter and gut healing gravy

    I find that it’s even easier for me to include ample fats with little bit of carbohydrate. I don’t believe cereals and doritos are even food, so I don’t consider those carbohydrates. I speak of properly soaked and soured grains, potatoes, fruits. These things my family thrives on to deliver those healthy fats.

  135. beaker says

    It’s a little scary to see people here promoting such much in animal products and animal fats. Many studies echo the below text:

    “The study found that men and women who eat a high protein diet which consisted of a high percentage of meat and cheese, had a higher risk of early death. The study found, on the other hand, that those that eat a high protein diet which consisted of mostly plant-based protein had a lower risk than average of early death.

    The study holds a lot of weight because it was far-reaching and included more than 85,000 women and 44,500 men studied for a period of 20 to 26 years. Lifestyle factors like alcohol intake, exercise, and multivitamin use were taken into account as well and the participants all started with a clean bill of health–no cancer, diabetes, or heart disease.

    According to the study:

    A low-carbohydrate diet based on animal sources was associated with higher all-cause mortality in both men and women.”

    Maybe these folks on LCHF diets don’t have brain issues because well… they don’t live long enough to. That’s one way around the problem I guess.

  136. Tom Boyer says

    This makes me so angry when people believe stuff like this. Beaker, nutritional epidemiology used to draw conclusions about what to eat is simply garbage science. There is a great discussion of this by Gary Taubes here:

    When you survey huge numbers of people on what they eat and then run correlations with health outcomes you WILL get correlations. if you have a large enough sample and a big enough survey, you can get hundreds and hundreds of correlations that meet the test of statistical validity. You can cherry pick them and get your name in the newspaper. But you don’t get causation and you definitely shouldn’t be drawing conclusions on what is safe to eat. What you don’t have is actionable knowledge.

    Say there is a correlation between people who report eating beef and bowel cancer. Say people who report eating beef are likely to eat it in the form of hamburgers with buns, and french friends and sodas. Maybe they’re also likely to smoke more cigarettes. Maybe they eat more fast food and watch more TV and spend more time in their cars and don’t care about their health generally.

    Meanwhile people who report eating less beef are more health conscious — they exercise, don’t smoke, maintain their weight, eat more vegetables and tofu. Maybe it’s the smoke, the sodas and white bread buns, the obesity and the lack of exercise that really causes the cancer. Maybe tofu prevents cancer. Or maybe it’s the sauce you put on the tofu. Or the sake you drink with the tofu. You can run all the regressions you want to TRY to control for factors like that but you really can’t get to the bottom of it. Patterns of behavior are very, very complicated.

    As Taubes rightly points out, survey type studies should be used to develop HYPOTHESES. The hypotheses need to be tested with controlled studies. And only THEN do you begin to have causation and enough information to make recommendations.

    The problem is controlled studies are expensive and, especially in the area of diet, very difficult to design. So unfortunately a lot of people in the dietary science field just SKIP THE ACTUAL SCIENCE and draw conclusions based on survey data. Which helps get them journal publications and grants and cushy jobs but doesn’t really advance our knowledge of what to eat.

    Really it’s terrible because not only are you getting pseudo knowledge, you may be actually recommending the OPPOSITE of what people should be doing to make themselves healthy.

    And that is how we got where we are today — with government policy recommendations for a “heart healthy” low-fat high-carb diet that has resulted in an epidemic of obesity, diabetes and Alzheimer’s.

    Bad science is making a hundred million people sick and causing what is increasingly looking like the greatest public health crisis in American history. We are literally eating ourselves to death here in the USA.

    • Megan Oien says

      I would add that these studies don’t differentiate between feed lot meat and grass fed/pastured. That is a huge factor. They aren’t even the same food. The Omegas are completely out of ratio in conventional meat.
      I think a lot of our problems come from grouping these foods together as the same thing. They are not. One is a food and the other a frankenfood. Same with organic vs non organic. It’s crazy that we even think in these terms. There is only what the body perceives as food and what it doesn’t. Anything it doesn’t perceive as food puts it in a constant state of inflammation.

      • says

        …not to mention, Dr. Perlmutter NEVER recommended heavy meat or cheese. I think he recommends 2-3 ounces of wild-caught, free-range, or grass-fed IF you even chose to eat animal protein. His recommendations are also completely compatible with a vegan diet.

        Beaker, you’ve clearly not read the book. Here’s a recent Medscape article that offers a great synopsis. Note, Dr. Perlmutter recommends GARNISHING with high quality meat.

        I’m guessing all these haters would realize Dr. Perlmutter’s recommendations are far from draconian IF they actually took the time to read the book. Just saying…

    • Marc says

      Here is one thing that we do know from a well controlled study by Dr’s Phinney and Volek.

      There is good evidence that the saturated fat circulating in your blood is a strong indicator of future heart disease.

      Phinney and Voleck have clearly shown that when you keep carbs very low and eat high levels of fat thereby becoming Keto adapted, the saturated fat circulating in your blood GOES DOWN.

      That may seem counter intuitive but when you are keto adapted you burn fat preferentially for your fuel. It doesn’t stay in your system very long as it is snapped up and quickly used for energy.

      When you eat too many Carbohydrates, your blood fat levels go up… Go figure

      So dont be too worried about observational studies that show low carb diets hurt you. Credible scientific evidence is quite the contrary.

      • beaker says

        Most people who think they are in “ketosis” are dreaming. Show me the blood work being taken every hour for weeks to confirm this. So at best most are likely swinging in and out of ketosis which is highly detrimental. Until personal (smart phone/device) 24/7 blood monitoring comes of age these people will not truly know if they are in ketosis or not. I think this tech will be available within 5years.

        • says

          I use ketostix throughout the day- not blood work- but pretty accurate. I’m fairly consistently in mild ketosis. Pass along your address & i’ll be happy to send them over ;-)

          • Mary says

            Hi Julie,

            Just wanted to jump in here to recommend that you visit Jimmy Moore’s posts on his nutritional ketosis experiment (n=1). He had compared the sticks and blood metering and claims that the sticks are extremely inaccurate. I’m not suggesting you are not actually in ketosis, just wanted to mention this in case you hadn’t read about it.

            • says

              Thanks, Mary.

              I am aware that ketostix are not as accurate as actually serum testing, but they are a useful tool. Jimmy’s podcast actually points out that IF you are not achieving a pink color, you may still be in ketosis IF your body is using the ketones as quickly as you are making them. Mine are pretty consistently pink, sometimes darker.

              I eat between 55-75 grams of carbs daily but also practice intermittent fasting and caloric restriction- contributing to my ketone production. I usually eat two meals a day and let 12-16 hours go between my last meal of the day and the first of the next- easy to do with a mildly ketogenic diet. This is an important part of Dr. Perlmutter’s protocol that I rarely see discussed. How we eat is just as important as what we eat. And, the importance of daily exercise must be emphasized. Diet alone is not enough. This is a lifestyle makeover.

              I have 2 copies of Apoe4. Statistically, I have very high odds of developing Alzheimer’s and CVD. Homozygotes, who live in developing parts of the world, do NOT go on to develop these Western diseases. These conditions are a direct result of our affluent society.

              • Mary says

                Hi July,

                Now I remember you from earlier in the thread, where you spoke about your high risk for Alzheimers. I would like to commend you for following such a careful diet to reduce your risks. That’s one of the main reasons that I really didn’t like this article–it seemed to be sweeping the keto diet as a means of Alzheimer’s completely under the rug. There was a woman who posted earlier that also had Alzheimer’s in her family who was quite relieved to hear Chris say that whole-food carbs were not an issue.

                Certainly, the keto diet is not for everyone. I have tried it to lose weight but it has not worked for me–and I am really tired of eating so much fat–so I am exploring other options. If I had Alzheimer’s in my family though, I would definitely be paying close attention to Perlmutter’s recommendations (even though there may not be hard scientific proof yet).

      • Mary says

        Hi Marc,

        I think this is a really important point that people tend to forget (I saw this in one of the interviews with them on youtube, but I had forgotten about it).

        The crucial thing to remember is that their study subjects were truly keto-adapted, such that fat really was the preferred fuel and thus got whisked out of their blood. Many people doing Paleo are not keto-adapted because they are not restricting whole-food carbohydrates/safe starches.

        Even the Perlmutter recommendation of 60 gr. of carb may not be keto for some people, who need to go quite low on carbs to start producing significant amounts of ketones.

        I for one feel that if a person is going to do really low carb, they are better to really do it right to ensure they are keto-adapted and burning all of the fat they eat.

        • Marc says

          Here is info from Phinney- Volek about their study that demonstrated a high fat diet lowers fat in your bloodstream:

          Comment. Among many original findings in this study of 40 people with metabolic syndrome put on either a high carb or a low carb weight loss diet, there were two that are extremely important. One, this is the first human study to show that humans who are keto-adapted have decreased blood levels of saturated fats despite eating more of them (Forsythe 2008). A couple years later we replicated this remarkable finding in a controlled feeding study in normal-weight men fed isocaloric weight maintenance diets (Forsythe 2010). Two, this study definitively demonstrated that being keto-adapted is associated with significant, across-the-board reductions in a host of biomarkers of inflammation. In a follow up paper, we published data showing that the low carb diet improved fasting and postprandial vascular function in response to a high fat meal (Volek et al. 2009).

  137. Tom Boyer says