Carbs & Alzheimer’s: Separating Fact From Fiction

Alzheimer’s, like many other inflammatory diseases, is a disease of civilization. We’re going to talk more about what that means. I think when you look at the history of diet policy and ideas around what’s healthy and what’s not, both for weight loss and metabolic problems and other conditions, early on, there was a really big focus on calories. All of the diets were focused on reducing your calorie intake. Then the focus really switched to fat. The idea was that fat was bad and the cause of all the problems, so we should all be on really low-fat diets. That was really destructive. Now the pendulum has swung in the other direction, where carbs have become the new evil macronutrient purported to be the cause of every problem. While I do appreciate some of the efforts that have been made to exonerate fat and point out the potential risks of excess refined carbohydrates, my concern is that we’re just doing the same thing we’ve done, which is demonizing a whole entire class of food, a macronutrient in this case, instead of focusing on what the real issue is.

In this episode, we cover:

2:37  What Chris ate for breakfast
7:23  Evolution of diet policy and ideas
15:36  3 common misconceptions about diet and disease
23:38  When a ketogenic diet may be helpful

Links We Discuss

• Do Carbs Kill Your Brain?

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Steve Wright: Good morning, good afternoon, and good evening. You are listening to the Revolution Health Radio show. This show is brought to you by 14Four.me. Now if you don’t know what 14Four.me is, it’s a 14-day healthy lifestyle reset program. If that’s still a little vague for you, basically, it’s for people like Chris and I who live busy lives and we have a hard time integrating diet, sleep, movement, stress reduction, all these components that go into making a very healthy life and a healthy family. Sometimes it can be very hard to integrate them all at one time. What Chris has done is he’s created a program called 14Four. It’s 14 days of incorporating these four factors into your life. So it’s very much a handholding program, where step by step, you’re going to be walked through just how you actually implement dietary changes, how you actually implement better sleep habits, how you actually reduce your stress, but not make it all about stress reduction because you have to move as well every day. It’s a really awesome program that you might want to do several times a year. A lot of people will be looking forward to doing something like this come January, which we’re only a couple of weeks away from. So if you don’t have your New Year’s resolutions planned out, check out 14Four.me. It might be something you want to try. We’re back to the Revolution Health Radio show. I’m your host, Steve Wright from SCDlifestyle.com. With me is integrative medical practitioner, healthy skeptic, and New York Times bestselling author, Chris Kresser. Chris, good morning.

Chris Kresser: Good morning, Steve. How’s it going?

Steve Wright: It’s going good, man. I’m just getting my first cup of coffee and starting the neurons to fire.

Chris Kresser: All right. Speaking of neurons, that’s what we’re going to be talking about today. I don’t know if that was a coincidence or a nice little lead-in. But I noticed you have your similar white cave in the background going now.

Steve Wright: Yeah. You know, RHR is getting really sterile these days. We’re going to have to throw up some artwork.

Chris Kresser: We’re all about audio quality, and our scenic background is suffering as a result. Maybe we need to hang some pictures in here or something.

Steve Wright: I think we need some family pictures, logos or something.

Chris Kresser: Yeah, something like that. So we have a great show, a really interesting topic, something I’ve covered a little bit in the past. We’re going to do it in a little more detail today. We have a good question from Kevin.

What Chris Ate for Breakfast

Steve Wright: Before we jump into that question though, did you have any special breakfast this morning?

Chris Kresser: I did have something different, I’m happy to report. It wasn’t plantains and eggs today. I had some winter greens cooked in broth. It’s a combination of kale and collards slow-simmered in broth. This was from last night, so leftovers. I had some lamb kefta, which is like spiced lamb patties. It’s made by a local charcuterie that I’ve talked about before, The Fifth Quarter, which I really love. Then some purple-fleshed sweet potatoes, which are my favorite type of sweet potatoes that are available in the fall. They have a really dense flesh. It’s not as watery as other kinds of sweet potatoes. I had a little bit of butter on that and a little bit of sauerkraut. So it was a good breakfast. We’re ready to go and talk about the brain.

Steve Wright: Awesome. Let’s roll into it.

Chris Kresser: Here’s the question from Kevin. Let’s give it a listen.

Kevin: Hey, Chris. I just had a quick question about Alzheimer’s disease and carbohydrate intake. The only reason why is because recently, the Mercola website has been putting out a lot of articles stating that any form of carbohydrate other than vegetable-based carbohydrates creates a sugar environment in the brain, where the brain has to create energy by metabolizing sugar rather than what it should be using, which is healthy fats. They make no differentiation between simple carbs or complex carbs, really no differentiation between glycemic index, where you’ve got sweet potatoes that have a good glycemic index, whereas maybe white rice would be a little bit riskier in that regard. Is there any basis to the claim that any non-vegetable-based carb is going to put your brain into an unhealthy state of processing sugars, which could maybe ultimately lead to a diagnosis of Alzheimer’s late in life? I also wanted to comment that there is just no possible way, as an active person who works out three to four times a week, that I could get enough energy from vegetable carbohydrates. I need 100 to 200 grams of white rice or potatoes per day just to keep my energy levels up. I’m concerned that since this is apparently a bad carbohydrate no matter what, that it’s putting my brain into a sugar processing state rather than a ketogenic state via healthy fats, and that this is a long-term agitator that might result in an Alzheimer’s diagnosis. Just curious about your thoughts on that.

Chris Kresser: This is a topic that I think has become increasingly relevant over the past several years. I think it’s pretty rare now to come across somebody—I’m sure almost everyone listening to this show, in fact, has been touched by Alzheimer’s disease in some way, whether it’s a family member, a friend, a colleague at work or someone in their life. It’s become a fairly shockingly common condition, and it’s pretty terrifying. When it comes to things that people fear in their old age, I’d say Alzheimer’s is probably right at the top of the list, because it’s extremely destructive. It’s extremely trying and challenging for people who are living with someone with Alzheimer’s. In fact, I remember reading a statistic that caregivers of Alzheimer’s patients have among the highest levels of stress of anybody that they’ve measured in terms of stress hormones. It’s one of the most stressful situations that you can be in. It’s a big problem, and it seems to be getting worse and worse. So I’m happy to have a chance to talk about it a little bit. I will point out that I wrote an article a while back that kind of addressed this question. It was called, “Do Carbs Kill Your Brain?” So if you want the CliffsNotes version, you can Google that. It should come right up to the top of the list. But we’re going to go over this in a little bit more detail.

Steve Wright: Is this going all the way back to the great starch debate?

Evolution of Diet Policy and Ideas

Chris Kresser: Yeah, it’s related to that. But actually, I wrote that article after Dr. Perlmutter’s book came out. I think he’s done some fantastic work. I applaud his crusade against industrial diet, processed and refined carbohydrates and food. But I think that he’s taken things a little bit too far in terms of associating all carbohydrates with brain disease. I don’t think there is a strong basis for that claim at all in evidence-based literature. Alzheimer’s, like many other inflammatory diseases, is a disease of civilization. We’re going to talk more about what that means. But I think when you look at the history of diet policy and ideas around what’s healthy and what’s not, both for weight loss and metabolic problems and other conditions, early on, there was a really big focus on calories. All of the diets were focused on reducing your calorie intake. Then the focus really switched to fat. The idea was that fat was bad and the cause of all the problems, so we should all be on really low-fat diets. That was really destructive. Now the pendulum has swung in the other direction, where carbs have become the new evil macronutrient purported to be the cause of every problem. While I do appreciate some of the efforts that have been made to exonerate fat and point out the potential risks of excess refined carbohydrates, my concern is that we’re just doing the same thing we’ve done, which is demonizing a whole entire class of food, a macronutrient in this case, instead of focusing on what the real issue is.

In my opinion, the issue is the quality of the food that we eat. Not even the quantity, although that matters. That’s primarily influenced by the quality though. And it’s not the quantity of macronutrients. In my opinion, it’s not primarily important for most people what quantity of fat, protein or carbohydrate they eat. What’s most important is the quality of those macronutrients. Getting your macronutrients from whole, unprocessed, real foods is probably the single most important thing that the vast majority of people need to focus on. Now, granted, there are people who have health conditions that require some tweaking in macronutrient ratios. I talk about that in my book. We’ve talked about that a lot on this show. But in general, quality is far more important than quantity. We know this from looking at the anthropological record and looking at things through an evolutionary lens. As I said before, Alzheimer’s, like many other modern diseases, is a disease of civilization. It’s not something that’s typically observed in traditional populations that are following their ancestral diet. We know that humans can thrive on a wide variety of macronutrient ratios. We’ve discussed this ad nauseam on the show. There are cultures like the Inuit and Maasai, who’ve eaten a relatively high-fat and low-carb diet, who are healthy and relatively free of modern disease. On the other end of the spectrum, we have cultures like the Kitava, the Tukisenta, and the traditional Okinawans, who ate a large percentage of their calories from carbohydrates and had a pretty low-fat intake, and were virtually free of modern inflammatory disease.

These are just examples of how it’s not the quantity of the macronutrients that matters, but the quality. Because what all those cultures weren’t eating are Cheese Doodles, Big Gulps, candy bars, lots of refined flour, and all of the stuff that really constitutes the basis of the American diet. I mean, 70% of calories now in the American diet come from flour, sugar, seed oils, dairy products, and alcohol. The majority of what people eat comes from that. So we’re not seeing an epidemic of disease because people are eating way too many bananas, way too many apples or too many sweet potatoes. We’re seeing an epidemic because people are eating junk. That’s what is happening in the industrialized world.

Another example of this is Weston Price and the research that he did. He studied traditional cultures who weren’t just following a Paleo type of diet. They were following a traditional diet that actually even included things like whole grains and legumes, which, of course, most Paleo advocates would say contribute to disease. I say that those things probably don’t contribute to disease in the context of a nutrient-dense, healthy diet. I mean, they may cause problems for some people who already have diseases and gut issues. We do recommend people avoid them for that reason. But once again, you don’t see big epidemics of disease, for example, when Price studied the traditional Gaelic populations, the traditional Swiss populations in the Lötschental Valley. These were people that were eating a fair amount of soaked and fermented grain products, in addition to dairy products and other real foods. There was no evidence of significant modern inflammatory disease in those populations either. So really, we see these diseases taking off when we see the introduction of white flour, industrial seed oils, and excess sugar. That’s the trio. Of course, on top of that are all of the other processed food that comes in bags and boxes that has become the mainstay of the American diet. But that’s not all.

We also have a disrupted gut biome. It’s become increasingly clear that our gut microbiome has changed dramatically even in the last 30 to 50 years. That’s had a profound influence on our health and our brain via the gut-brain axis, which we’ve talked about a lot. There are things like environmental toxins, an increase in chronic stress, a decrease in sleep. In the last 50 years, we’ve gone from sleeping an average of eight hours a night to, in many cases, sleeping an average of six hours a night. So we’ve lost a couple of hours of sleep in 50 years. That has a profound impact on brain health. There’s not enough exercise. Then there’s some evidence that chronic infections may play a role in certain brain disorders. I’m actually not even aware of a single study correlating the development of Alzheimer’s with consumption of carbohydrates from natural sources like fruits and vegetables. The problem is that most of the studies look at carbohydrates as a whole class. They don’t differentiate between different kinds of carbs. Those studies will show an association between carbs and brain disorders. Why? Because over 80% of the carbohydrates that are consumed in the US are in highly refined form. We’re talking about sodas, flour, cookies, crackers, cake, muffins, bread, cereal. This is all the stuff that the average American is eating on a daily basis. They’re not eating sweet potatoes, plantains, yuca, taro, not even whole grains.

Steve Wright: White potatoes, rice.

3 Common Misconceptions about Diet and Disease

Chris Kresser: Even whole potatoes or rice. Yeah. These are things that are not commonly eaten. So to blame a condition like Alzheimer’s on those nutrient-dense starches and whole fruits I think is completely unfounded and problematic, because it’s pushing people to a very low-carb diet, which we’ve discussed again. I read a whole series about that. There’s even an eBook available now on my site about that. Low-carb diets, they can be therapeutic in some cases, but they can cause a lot of harm in people who aren’t well-suited to them.

Steve Wright: Yeah. This is really scaremongering in the alternative community, is what this is. The people listening to this show I think—hopefully the show will reach a bigger and bigger audience who needs to hear that whole foods are the key. But the idea that every protein is the same or every fat is the same—when you talk about the difference between industrial seed oils, the difference between healthy fats, as an alternative health community, it’s not for us to lump all carbohydrates together. It’s just bad science. It’s irresponsible.

Chris Kresser: I think so too, Steve. It’s always been just crystal clear to me, but it’s amazing to me that there’s still a debate about that. There’s still people who are hanging on to that idea, that all carbs are the same no matter where they come from, in spite of the overwhelming amount of evidence that suggests that’s not true. I think part of the issue that makes this confusing for people is that a ketogenic or very low-carb diet can be really therapeutic for a lot of conditions, including Alzheimer’s. So the assumption is then made that because it’s therapeutic, because removing carbs from your diet is therapeutic for a particular condition, then that means that carbs were the problem in the first place. It is easy to see how someone can make that leap, but it’s actually a fallacy. It’s a logical fallacy. Those two things don’t go together necessarily.

Let me give you some other examples where that assumption could be made, but it’s obviously untrue. One would be hemochromatosis, which is a disorder of excess iron storage. Most people, when they eat foods that contain iron, they only absorb the amount of iron that they need and then they excrete the rest of it. But people with hemochromatosis, their body isn’t able to sense how much iron they already have stored. They end up absorbing more iron from the food than they need rather than excreting it. The iron accumulates in their body over time, and that causes problems. Of course, as you can imagine, one of the treatments for hemochromatosis is reducing your intake of iron. Makes sense, right? But that doesn’t mean that everybody should eat less iron, nor does it mean that eating too much iron is what led to hemochromatosis in the first place. It’s not caused by eating too much iron. It’s actually caused by a genetic mutation that leads to that excess iron storage and that disruption in iron metabolism in the first place.

Another example that a lot of people will be able to relate to is people with Celiac disease or gluten intolerance need to avoid gluten. But that doesn’t mean that eating gluten is what originally caused the Celiac disease or the gluten intolerance. Otherwise, every single person that ate gluten would have Celiac disease or gluten intolerance, but that’s not actually true. Celiac has a genetic predisposition, as does possibly non-Celiac gluten sensitivity. There are also a bunch of environmental factors, triggers, that can increase the risk of Celiac developing, such as leaky gut. Dr. Fasano, who we’ve had on the show, believes that leaky gut is a precondition for developing any autoimmune disease, including Celiac disease. So you have a genetic predisposition, plus, for example, taking antibiotics when you’re a kid or not being breastfed or being born via C-section. That disrupts your gut microbiome, and then that predisposes to the development of Celiac disease. That’s the second example.

A third example might be that people who don’t have a gallbladder may need to limit their fat intake a little bit, because bile is really helpful in breaking down fats. People without a gallbladder don’t produce as much bile. But eating a higher-fat diet is not usually the cause for gallbladder disease and having to have your gallbladder removed in the first place. In fact, gluten intolerance is one potential cause that can lead to having your gallbladder removed. I hope you can see, from these examples, that the fact that a low-carb diet is therapeutic for a certain condition does not mean that carbs led to that condition in the first place. This, again, is common sense. But I can see how people could get thrown off or confused by it. Hopefully, that clarifies a little bit.

Steve Wright: Yeah. And my anger and I think Chris’s passion as well is not directed towards those people who are trying to make sense of this condition. It’s directed at the people who are giving out information regarding this condition. Because when you do have somebody in your life who’s sort of beginning to forget what life is and who they are, I mean, it’s very tragic, and so you want answers like now. When the pain is as great in a condition like Alzheimer’s, I think it’s very easy to try to just jump—like, you just want to make changes as fast as possible.

Chris Kresser: Like I said, I think Dr. Perlmutter has done some great work. I think he really believes in what he’s doing and saying—actually, I don’t really know. I’ve never talked to him about that. I know he’s gone on Robb’s show and he’s said yes, he does really believe that everybody needs to be on a really low-carb diet, even athletes. I think he just has a different perspective on things. But I think I’m coming from a place where I actually see potential harm in that approach, because I work with patients who’ve been harmed by that approach, as I’ve said many times before. I don’t see the evidence supporting that idea, that natural carbs can contribute to diabetes. In fact, we have quite a bit of evidence that suggests the opposite.

When you look at studies, and I mentioned these studies in the, “Do Carbs Kill Your Brain?” article—and there’s one that actually has recently come out. A study came out after I wrote that article, just a few days ago actually, that showed that people in the highest quartile of fruit and vegetable consumption—so they divided people into groups based on how much fruit and vegetables they ate on a daily basis. The people that were in the highest group in terms of consumption had an 81% lower risk of developing diabetes than people who ate the least amount of fruits and vegetables. So when you see studies that actually look at consumption of whole food sources of carbohydrates, and even studies that have just looked at fruit independently from vegetables, have seen almost always that there’s an inverse relationship between the amount of fruit and vegetables that somebody eats and their risk of getting diabetes. To me, that just goes to show that when a study shows that carbs are contributing to diabetes, whether we’re talking about type 2 diabetes or type 3 diabetes, which is what Alzheimer’s has been referred to, it’s not coming from fruits and vegetables. It’s coming from the industrialized products that we’ve been talking about.

When a Ketogenic Diet May Be Helpful

Now that we’ve got that out of the way, let’s talk a little bit about what is actually happening with Alzheimer’s, and what might be some of the options in terms of dealing with it. I hope I’ve established that eating nutrient-dense carbohydrates does not contribute to it. Now we’re going to talk a little bit about what you might do if it’s already there, you know, for a family member or someone that’s dealing with it. Again, just as a reminder, I’d like to be ultra clear that this is separate from what you would do to prevent, because they’re not necessarily the same thing.

Alzheimer’s disease essentially involves abnormal metabolism in the nerve cell. There’s evidence that these nerve cells in people with Alzheimer’s can’t process glucose in the normal fashion to meet the cell’s energy needs. That’s due to insulin resistance in the neuron that makes it hard for the brain to use glucose. When not enough glucose can be burned efficiently, then the neurons are prone to not working properly, malfunctioning, and even death. So the principle behind using a very low-carb diet as a therapy for Alzheimer’s is that when the carbohydrate intake is restricted, ketones will be produced, so this is a ketogenic diet. And the brain can use those ketones as an alternative fuel source to substitute for glucose, which, in turn, will improve the function of cells and maybe even stop them from dying. That, again, doesn’t mean that eating too much glucose cause the metabolic problems or insulin resistance in the first place. But once those problems are there, then switching to ketones as the primary fuel source for the brain instead of glucose can be therapeutic.

Ketones, for those of you that aren’t familiar, they’re made in the liver from fatty acids or amino acids. According to the studies I’ve seen, about 60% of the brain’s energy needs can be met by ketone bodies. So if a nerve cell or neuron only has 40% capacity to use glucose, then the ketones could conceivably compensate completely for the glucose that cell would otherwise be using, and it could make up for the shortfall in function. The brain’s ability to use ketones actually is an evolutionary adaptation that came out of times in our history when glucose was scarce. For example, during periods of extreme food scarcity or during periods where there was a shortage of carbohydrates in the diet. You know, the brain is the most important organ in the body, so from an evolutionary perspective, we needed to evolve a way where the brain would work in pretty much any environmental circumstances, regardless of what types of food were available. What’s interesting to me is that people have said, “Oh, this is our sort of optimal, desirable state.” When you consider the evolutionary perspective, you can see that this was an adaptive mechanism for very extreme circumstances, right? Circumstances that weren’t likely to be encountered by most people during most of their lives. So to me, it’s an adaptation that can be used when it’s necessary, but it’s definitely not our default state. It’s not our default state or necessarily even our optimal state. This is an adaptation for pretty extreme circumstances.

So the discussion of how you actually put this into practice is probably beyond the scope of this show, but I do want to hit a couple of highlights. Paul Jaminet from Perfect Health Diet has written about using ketogenic diets for brain disorders. Kurt Harris, who some of you might remember from back in the day as a very popular Paleo blogger, has not been blogging for quite some time, but he’s a friend of mine and I stay in touch with him. I know he’s done a lot of research and work on this subject. He’s shared it with me. He hasn’t written about it publicly. But both Kurt and Paul, who are really smart guys and have spent a lot of time looking into this, their approach, which is my approach as well in the clinic, is to force ketone production with high amounts of medium-chain triglycerides (MCT) like MCT oil or coconut oil, rather than using a super, super low-carbohydrate diet. For example, a typical ketogenic diet might be limiting carbs to 25 grams per day, including carbs from non-starchy vegetables. My approach, Paul’s approach, and Kurt’s approach would be more like using a high level of MCT oil, maybe like a 50/50 mix of MCT and coconut oil, 6 to 9 tablespoons a day of that, to force the ketone production. And restricting carbs, but not restricting them so heavily. We might go for like 50 to 75 grams of carbohydrates, but not even counting carbohydrates from non-starchy vegetables. So just counting them from fruit and starch, and limiting to maybe 50 to 75 grams, and using the Ketostix to see how much carbohydrate you can tolerate and still remain in ketosis with that level of MCT and coconut oil. The reason for that is that there are some potential side effects from being on an ultra low-carbohydrate diet over a long period of time. Those can be largely mitigated by eating 50 to 75, or even 100 grams total of carbohydrates, and you still get the benefits of being in ketosis. So that’s I think the best approach in these kinds of circumstances, when a ketogenic diet is necessary. Maybe in another show, we’ll get more into the details of how to do that or I’ll write an article about that if there’s some interest in it, which I imagine there would be, given how prevalent these problems have become. I think that’s it, Steve. Anything else that comes to mind?

Steve Wright: I think a big takeaway is that, in case people didn’t grasp it yet, is that you will alter the fuel that you feed the system based on how the system’s doing. For instance, if you buy a diesel truck, you’re going to put diesel fuel in it. You’re not going to put high-octane airplane fuel or regular-grade car fuel in it because it’s a different type of engine. That analogy could transfer over. Some of us have Ferrari engines. Some of us have diesel engines. Some of us have just regular Volkswagen engines. Based on how you’re running the system, you’re going to need different types of fuel. So the fuel source really matters, that you get the right fuel source based on what the engine is. I think that’s really important for the discussion, both pre-disease and then after the disease has started to set in. You always have to kind of match those things.

Chris Kresser: Yeah, exactly. One of the main points I made in my book or tried to make was that there’s no one-size-fits-all approach. Not only that, there’s no one-size-fits-all approach for one person throughout their life.

Steve Wright: Yeah.

Chris Kresser: That’s what you were just getting at, Steve. It could be that earlier on in life, a higher-carb, lower-fat diet, for whatever reason, would make somebody feel better. But then later on in their life, due to changes—you know, maybe they took a lot of antibiotics early on and later in their life, or they got a bunch of parasites and their gut microbiome got really screwed up, and then that causes a systemic inflammatory condition and leaky gut, which, in turn, led to the development of epilepsy, Parkinson’s or Alzheimer’s later in their life. Maybe they were burning the candle at both ends or whatever, and they developed Alzheimer’s, and then the diet that they were eating before that was working for them well is no longer going to work, because their glucose metabolism in the brain has become impaired, and they need ketones to substitute for that. So it’s really all about paying attention, listening to your body’s needs, using smart testing and diagnosis to figure out what your body’s needs are, and then adjusting your diet and lifestyle as you go based on those things. That’s what the idea of a personal Paleo code is, because it’s not really simple—you know, we share a lot in common, but we have a lot of important differences. This is why it’s not possible to prescribe one approach that will work for everybody, or even one approach that works for one person throughout their entire life.

Steve Wright: Well put.

Chris Kresser: Hopefully, this has been helpful. Let us know if you want us to go into more detail about implementation of the ketogenic approach. I think generally, it’s best to do under the supervision of someone who’s skilled in this, because there are a lot of moving parts and there are definitely things to consider. But perhaps we can cover it to some degree without being irresponsible about it. I guess that’s what I’m trying to say.

Steve Wright: Well Chris, this is the end of basically our Thanksgiving show. As we head into the holidays here, I just want to say that I’m grateful for you, grateful for the work that you do, and grateful for the listeners out there who listen to this show.

Chris Kresser: Thank you, Steve. I’m grateful as well for your support and Jordan’s behind the scenes. All of you folks who are hearing this, it’ll be a couple of weeks after Thanksgiving by the time you hear this. But I hope you had a great holiday and lots of joy and connection with family and rest. Going into the holidays in December, I wish you the same. We’ll be back next time.

Steve Wright: We sure will. In-between episodes, if you’re looking for more information from Chris, like things on carbohydrates as they come out in the research, make sure you’re following him on Facebook. Go to Facebook.com/ChrisKresserLAc and Twitter.com/ChrisKresser. Thank you for sending in your questions. Please keep doing that in-between shows. We’ll see you on the next episode.

Chris Kresser: Bye-bye.