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Red Meat & Cancer—Again! Will It Ever Stop?


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The media and blogosphere are abuzz with the latest report from the WHO, which classified cured and processed meats as carcinogens and put them in the same category as asbestos, alcohol, arsenic, and tobacco. But what does the research really tell us about the link between red meat and cancer?

meat causes cancer myth
Red meat is associated with many things, but cancer isn't one of them. istock.com/LauriPatterson

Well, here we go again. Each year, like clockwork, the conventional medical establishment mounts an attack against red meat.

For decades, we were told not to eat it because of the cholesterol and saturated fat it contains. When that argument became less convincing, a new one was offered: we shouldn’t eat red meat because it increases production of a compound called TMAO, which causes heart attacks.

Now we’re being told not to eat red meat—and especially cured and processed meat—because it will give us cancer. In a recent report, the World Health Organization (WHO) ranked bacon, sausage, and other cured and processed meats as “group 1 carcinogens,” which puts them in the same category as tobacco, asbestos, alcohol, and arsenic. It also placed fresh red meat in the “group 2A” category, which suggests that it is “probably carcinogenic” to humans.

Of course, this isn’t a new argument; it’s been around for at least 40 years. As far back as 1975, scientists speculated that the consumption of animal products was linked to cancer. (1)

How Strong Is the Evidence Linking Red Meat to Cancer?

However, the evidence supporting this claim has never been as strong as its proponents suggest. I have critically reviewed this evidence on several occasions in the past, as have many of my colleagues. Here’s a list of a few articles and podcasts I recommend reading and/or listening to if you’d like to go deep on this topic:

I realize that many of you don’t have the time to sift through all of that material, so I’ll do my best to summarize the salient points here.

Is eating bacon the same as smoking cigarettes when it comes to cancer?

Let’s start with a critical review of the evidence linking red meat to cancer that was published in one of the most prestigious scientific journals in the world (Obesity Reviews) in 2010. (2) The authors looked at 35 studies that claimed to find an association between red meat and cancer and found numerous problems. Here are some key passages from this paper, with my commentary.

Collectively, associations between red meat consumption and colorectal cancer are generally weak in magnitude, with most relative risks below 1.50 and not statistically significant, and there is a lack of a clear dose–response trend.

Translation: the association between red meat and cancer is not strong (i.e. comparing bacon to cigarettes is absurd), and in fact is often not distinguishable from chance. If red meat really did cause cancer, you’d expect to see a linear (continuous) increase in cancer rates as red meat consumption increased. But that’s not what we see in many cases. In fact, in some studies you actually see a decrease in cancer rates in the people who ate the most red meat. (3)

Results are variable by anatomic tumour site (colon vs. rectum) and by gender, as the epidemiologic data are not indicative of a positive association among women while most associations are weakly elevated among men.

Translation: the studies claim that red meat causes different rates of cancer in different parts of the intestinal tract, and different rates in men and women. For example, in the study I just referenced above (#3), there was an inverse relationship between red meat intake and colon cancer (meaning people who ate more red meat had less colon cancer), but a positive relationship between red meat and rectal cancer. And in an analysis of data from the Women’s Health Study, researchers found a strong (and linear) inverse relationship between red meat consumption and colon cancer. (4) Without a clear explanation of why red meat would be prevent some types of intestinal cancer while contributing to others, and have different effects in men and women, the likelihood of a causal relationship between red meat and cancer is reduced.

Colinearity between red meat intake and other dietary factors (e.g. Western lifestyle, high intake of refined sugars and alcohol, low intake of fruits, vegetables and fibre) and behavioural factors (e.g. low physical activity, high smoking prevalence, high body mass index) limit the ability to analytically isolate the independent effects of red meat consumption.

Translation: the studies linking red meat and cancer are plagued by “healthy user bias.” This is a fancy way of saying that people who engage in one behavior perceived as healthy are likely to engage in other behaviors they perceive to be healthy. On the flip side, people who engage in one behavior perceived to be unhealthy are likely to engage in other behaviors perceived to be unhealthy.

In an ideal world, we would be able to conduct a randomized, controlled trial to determine whether red meat causes cancer. We’d create two groups of people that are relatively similar in age and other characteristics. Then we’d isolate them in a medical ward, strictly control their diet, exercise, and other lifestyle factors, and then feed one group more red meat and the other group less.

Unfortunately, this will never happen. Cancer can take decades to develop, so these poor souls would be living in a ward for at least 20 years. Even if we could find people to volunteer for such a study, it would be astronomically (and prohibitively) expensive.

As a result, we’re left to rely on observational studies to shed light on the question of whether red meat causes cancer. The problem with this is that observational studies do not prove causality—they just demonstrate an association, or relationship, between different variables. Sometimes the association is causal, and sometimes it’s not.

Let’s consider red meat. Regardless of whether consuming fresh and/or processed red meat is unhealthy, it has certainly been perceived that way for the past half-century in the industrialized world. What this means is that people in observational studies that eat more red meat also have a tendency to smoke and drink more, eat fewer fresh fruits and vegetables, exercise less, and engage in other unhealthy behaviors that could influence cancer risk. This isn’t just speculation; it has been shown in numerous studies. (4, 5)

For example, most Americans that eat red meat eat it with a huge bun made of white flour, with a serving or more of other refined carbohydrates (chips, fries, soda) cooked in rancid, industrially processed vegetable or seed oils. How do we know that it’s the red meat—and not these other foods—that is causing the increase in cancer?

The better observational studies attempt to eliminate the influence of these other factors, but in practice that is difficult if not impossible.

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You Can’t See What You’re Not Looking For

What’s more, there are certain factors that are likely to play a significant role in the relationship between any food that we eat and cancer, but to my knowledge, have never been adequately controlled for in any study.

One of these is the gut microbiome. Previous work has shown that the composition of the gut microbiota may directly affect the influence of dietary factors on cancer risk. (6)

For example, Streptococcus bovis, Bacteroides, Fusobacterium, Clostridia, and Helicobacter pylori have been implicated in tumor development, whereas Lactobacillus acidophilus, L. plantarum, and Bifidobacterium longum have been shown to inhibit colon carcinogenesis. (7) Other studies have found that certain species of bacteria were higher in populations with high colon cancer risk, while other species were higher in populations with low colon cancer risk. (8) Finally, a recent paper compared the gut microbiota of 60 patients with colorectal cancer with that of 119 normal controls. The patients with cancer had significant elevations of Bacteroides/Prevotella (both species that are recognized as potentially harmful) when compared to the control group, and the difference was not affected by general patient characteristics (e.g., age, body mass index, family history of cancer), tumor size or location, or disease stage. (9)

We still have a lot to learn about the influence of the microbiome on health and disease, but we know enough already to conclude that it is significant. It is possible—and I would argue likely—then, that the variability we see in studies showing an association between red meat consumption and cancer may be in part due to the status of the patient’s microbiome.

In other words, a patient with a dysbiotic (i.e., compromised) microbiome may be at increased risk for cancer if he or she consumes high amounts of either fresh or processed red meat. But a patient with a normal, healthy microbiome may not be.

There is, in fact, some research that hints at this possibility—though it wasn’t what the study authors intended. A couple of years ago, scientists from the Cleveland Clinic published a paper linking red meat consumption with the production of a compound called TMAO, which has been associated with cardiovascular disease.

That paper was riddled with problems (which I outlined in this critique), including the most glaring one—that several foods, including seafood, increase TMAO production by a much greater margin than red meat. However, there was one section of the paper that I found to be very interesting.

It showed that omnivores who eat red meat produce TMAO, whereas vegans and vegetarians who hadn’t eaten meat for at least a year do not. The researchers claimed that this means eating red meat must alter the gut flora in a way that predisposes toward TMAO production.

However, there’s another explanation that I believe is much more plausible: the red meat eaters are engaging in unhealthy behaviors that lead to gut dysbiosis. This could include eating fewer fruits and vegetables and less fermentable fiber, while eating more processed and refined flour, sugar, and seed oils. All of these behaviors have been shown to be more common in the “average” red meat eater, and all of them have been associated with undesirable changes in the gut microbiota. (10, 11, 12)

Apples and Oranges (Or, Paleo vs. Standard American Diet)

Observational studies are useful for generating hypotheses and identifying general trends. But another limitation they suffer from, in addition to those I’ve described above, is that they aren’t able to detect the effects of crucial differences between study participants.

Consider two different people. One follows a standard American diet, doesn’t exercise much, and has a compromised gut microbiome. The other follows a Paleo-type diet, exercises regularly, and has a healthy gut microbiome. In an observational study looking at the relationship between red meat and cancer, at least 95 percent (if not more) of the red meat eaters in typical studies will fall into the former category. If the study concludes that there is a link between red meat and cancer, the 5 percent of the participants that eat a healthy diet, exercise, and have a healthy gut—and are thus highly unlikely to experience the same impact from eating red meat—will be lumped together with the other 95 percent.

Put a different way, it should be fairly obvious, given what we already know about the influence of diet, lifestyle, and the microbiome on cancer risk, that someone following a Paleo-type diet and lifestyle will not share the same cancer risk as someone following a Standard American Diet and lifestyle, even if they are eating an equivalent amount of red meat. Yet these two groups of people are always lumped together in the studies and media reports. This is a huge problem in research, and it has not been adequately addressed.

What’s the Bottom Line?

Even if you ignore everything I’ve written in this article and accept the WHO report at face value, just how much would your risk of cancer increase if you eat cured and processed meats?

About three extra cases of bowel cancer per 100,000 adults. That means you have about a 1 in 33,000 chance of developing bowel cancer from eating cured and processed meats.

This is a far cry from how much smoking cigarettes, which the WHO now classifies in the same category as eating bacon and salami, increases your risk.

As Professor Ian Johnson of The Institute of Food Research said in an interview with The Guardian:

It is certainly very inappropriate to suggest that any adverse effect of bacon and sausages on the risk of bowel cancer is comparable to the dangers of tobacco smoke, which is loaded with known chemical carcinogens and increases the risk of lung cancer in cigarette smokers by around twentyfold.

What’s more, the report from the WHO classified 940 other agents, along with red meat, as potential carcinogens. In the Guardian article above, Betsy Booren, the vice-president of scientific affairs for the North American Meat Institute, put it in perspective:

The IARC says you can enjoy your yoga class, but don’t breathe air (class 1 carcinogen), sit near a sun-filled window (class 1), apply aloe vera (class 2B) if you get a sunburn, drink wine or coffee (class 1 and class 2B), or eat grilled food (class 2A). And if you are a hairdresser or do shift work (both class 2A), you should seek a new career.

At this point, given what the research indicates, I do not feel that modest consumption of cured or processed meat is likely to pose a significant health risk, provided you are doing other things right (i.e., nurturing your gut microbiome, eating nutrient-dense, real foods, exercising, etc.). I think there is even less evidence suggesting that we should limit consumption of fresh red meat, especially when it is cooked using gentle methods (rather than charring it) and when you eat “from nose to tail.”

Okay, that’s it for this year’s installment of “red meat won’t kill you.” See you next year!

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Join the conversation

  1. You failed to mention The China Study, probably the most compelling argument against meat. Thoughts?

  2. Many scientists turn out to be anything but, and survive only because of society’s addiction to credentialitis. This is an epidemiological study which implies it is likely to be mostly nonsense, not my opinion but that of one of the world-leading epidemiologists. http://seedmagazine.com/content/article/dirty_little_secret/
    Only about one in ten papers based upon studies is worth reading because that’s how few stand up to subsequent critical analysis and attempts to confirm the data. An easy way to avoid wasting time reading junk papers is to ignore any paper where the data does not show a difference from a current norm of greater than two to one. Only in rare cases do those below this mark stand up to subsequent careful analysis and attempts to duplicate the data. We’ve noticed the withdrawal of numbers papers is accelerating as more of us go after nonsense data. The number of cases of outright data fraud by individuals and being caught seems also to be rising. Currently the National Nutritional Guidelines is in the process of crashing and burning while those responsible for the guidelines are attempting a soft landing employing the diversionary tactic of replacing “villain fat” with “toxic sugar”. In the update of the Guidelines of a few years ago the science individuals responsible for them refused to reveal who they were and remained strenuously anonymous despite all attempts to smoke them out. To me that was a stronger indication of guilt than taking the fifth. I don’t blame them for trying to hide; I would fear a class-action personal injury suit too.

  3. In recent years, studies were published linking bowel cancer to infectious agents in certain types of red meat, especially from European/American dairy cows (bos taurus). The suspected mechanism is that cancer is in some cases an infectious disease, with a mechanism similar to the link between HPV and cancer.

    Right now, in my opinion, this is all mere speculation and far from conclusive evidence but still I am curious what you think of it?

    Here are some of the mentioned studies:

  4. Recent interview with Dr Dean Ornish here giving his side of the debate


    • Sorry repost of link


      • It appears that the site does not allow me to post links or is it links to plant based advocates as I am sure I have posted links before

  5. I’m disappointed that Chris K. focused on the broad topic of red meat, when the WHO report mostly condemned processed meat. I still have no clarification on bacon. 🙁

    • You are unlikely to get a confident answer, bacon may be bad for you on the other hand it may not. There is an association but not a proven cause. So what do you do and here is my point stated previously. Fortunately we don’t have to take a chance. We do not live in world where bacon is the only source of food. There are plenty of other foods that do not have associations with ill health. Simply substitute those foods for bacon and sleep at night.

      • It may not be bad for you? That is wishful thinking supporting your addiction…

  6. Is it really red meats or is it the antibiotics, corn, wheat, mold that the animals are being fed???

  7. Chris,

    Do you know of or are there any experimental results showing how much of these nitrites/nitrates can be removed from bacon. I’ve searched the internet for hours and haven’t found any empirical findings. I have to stay on a low carb, low sugar diet to keep my Diverticulosis in check. I eat 20-25 strips of bacon every morning with Better “N eggs cooked on low heat in 4 TBLS of EVOO. I soak the bacon in cold water for about an hour before I cook it. (microwave). I also change the water in the bacon three or four times while it soaks. I’ve noticed that the bacon isn’t nearly as salty after soaking. In fact it barely has any taste at all but it does give breakfast more protein. Does the fact that the salty taste is gone mean that the nitrites/nitrates are GONE???
    Please post any experimental results you’ve found.


    • Triblig To me it sounds like you’re taking good precautions in the preparation but then you’re ruining the the bacon by microwaving ( nuking ) it, food that is microwaved is dead food devoid of any nutrients and the food molecules altered & destroyed by the nuking process. Microwaves do even more harm to the body, check it out. I put my microwave unit out to the curb 10 years ago & even cut the cord so it won’t be harming anyone else who might have noticed it there want to pick it up take it home and use it ..

      • Ida, Chris posted something on Microwaves earlier this year –
        http://chriskresser.com/are-microwave-ovens-safe/ , where he mentions:

        “Do microwaves destroy nutrients?

        As far as vitamins, minerals, antioxidants, and plant phenols, retention does not appear to depend on cooking method. Levels of nutrient retention were sometimes higher in microwaved food, and sometimes lower, depending on time, temperature, and amount of water used in the cooking process. (16, 17, 18, 19, 20)

        In general, nutrients are lost from food during any type of cooking, and more nutrients are lost when the temperature is higher or the food is cooked for longer. Water soluble vitamins are readily leached into cooking liquid (no surprise there), so boiling food tends to result in greater nutrient losses than microwaving it with a small amount of water (unless you drink the water you boiled the food in, in which case you’d still be getting most of the nutrients). ”

        So I really don’t think you should be claiming that anything cooked in the microwave is devoid of nutrients.

        • The meat causing cancer- colon cancer is complwetely worng,. I was a natural unprocessed foods vegetarian for 30 years and in my 40s had colon cancer- how so? from a prescription statin drug- one pill for several years and “that” resulted in cancer in the past. Drugs cause cancer, not meat. Drugs are made from petrochemicals! basically fractitioned toluen and road tar in the making of them- as I found out years later.

      • gh- if pig meat is “immunosuppressive”, how is it that the older Okinawans are so healthy? Traditionally they ate pork, and used lard for cooking. In fact many very healthy groups of people eat pork regularly, and our ancestors have been eating wild pig for quite awhile. What evidence do you have that it is “immunosuppressive”?

  8. Sounds to me like someone refused to pay extortion money or something like that. WHO and similar organizations don’t give a damn about people’s health; their driving interest is the continuation of their own existence. So, they have to come up with something startling on a regular basis. Truth and good science are meaningless in the face of their need, and greed, for power. I put the FDA firmly in the same category. I will continue to use my own good sense to eat the food Creator put here for us.

  9. That Obesity Reviews report (2) was done by Exponent, Inc.


    “The quality and neutrality of reports produced by the company have been called into question on various controversial topics. Common points of critique include corporate denialism and that, for industrial clients, only favorable reports are seemingly produced. Examples include Exponent arguing that dioxins do not cause cancer.”

      • In the 1930’s Weston Price did a 9 year worldwide study on the healthiest peoples compared to their sickly neighbors. In a nutshell he found the healthiest people ate the most meat/ saturated fats and the least adulterated foods, which at the time were canned or refined flours and sugar (1890’s industrial revolution allowed these to sneak into the diet). You can read the actual study and see the pictures comparing what really healthy person looks like compared to an underdeveloped and sickly one looks like, something we have gotten used to that we call genetics or individual variation. In fact, we are used to seeing sickly people such that we think it is normal. The book is Nutrition and Physical Degeneration by Weston A Price and google those terms and free PDF. Also research the archives of follow up info at westonaprice dot org.

        • If you can source and eat similar meat found in those countries in the 1930’s then I agree your chances of a long and healthy life are much better than the standard western diet. I am not sure that I can consistently do that so I choose to not eat red meat, only wild fish and occasional organic white meat

      • As an 83-year-old great grandfather with diagnoses of hypoglycemia, non-celiac gluten sensitivity, carbohydrate intolerance, etc., I’m thriving thanks to exercise, very little meat, some fish, lots of veggies, but no fruit, alcohol, caffeine, sugar, wheat or dairy. Life is still very much worth living. The internet and bloggers like Kresser and Perlmutter have helped me enormously to figure out how to cope with the various challenges that have come my way and it ain’t over yet!

  10. I also read the WHO report and made similar points in my recent blog post and podcast. As you noted, the evidence did not include randomized controlled trials (the gold standard) but was based on cohort and control-case studies, which lack the same scientific rigor. I emphasized that the results do not mean that red meat causes cancer but only that that some associations were made. The only statistically significant association (>95% confidence interval) was between the risk of colorectal cancer and people who ate at least 50 grams of processed red meat and 100 grams of unprocessed meat daily. To put this in perspective, 1 standard slice of raw bacon is about 1 oz. or about 28.35 grams.
    An important finding that seems to have been overlooked by the WHO working group was in a large case-control study (Preston-Martin, et al., 1996). Mothers who ate cured meat and vegetables, did not have a positive association with childhood brain tumors because the Vitamin C (ascorbic acid) inhibited the formation of N-nitroso-compounds (NOCs).
    My recommendations:

    1) Get daily protein from a variety of sources including grass-fed unprocessed meat, pastured chicken, wild-caught fish, free-range eggs, nuts, seeds and gluten-free grains if not strictly Paleo.

    2) Eat lots of vegetables and fruit with Vitamin C (use supplements if needed), which can inhibit the formation of NOCs.

    3) Don’t eat processed meat daily and in large amounts. Buy organic brands that are nitrate and nitrite free, which are precursors to NOCs.

    4) Do not pan-fry meat at high temperatures which may change the DNA of muscle meat and increase the risk of chemicals called heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs).

    • For those people with limited budgets and or limited knowledge of the subject the safest option is to avoid meat and become a veggie and supp’ with a multi Vit B tablet. If you have the money and the interest then navigate your way through the meat trap. The problem is that expressing the opinion as some do that this WHO report is overplayed will mean that the former group of people will continue consuming meat and in particular processed meat. Sometimes its case of whats the most simplest and healthful message.

      • And who are you to advise people on what they should do, Mark? A big problem (as I see it) is that foods are constantly being labeled “bad”, until later on, they may be pronounced “good”. I remember when I was a young adult, we were told that avocados were “bad” because they were so high in fat. I continued to eat them because I liked them, and craved them (probably because my body needed the fat I wasn’t getting from my low fat diet). Several people told me I was risking my life by eating 1/2 avocado every day, maybe I would get heart disease. That was the prevailing wisdom at the time. And now, lo and behold, avocados are currently considered a “superfood”. These things keep changing, and epidemiological studies don’t tell you much.

        Also, it’s far better to get your B-vitamins from food, if you can, than from a pill.

        • I remember when I was a kid, my home and most others would have bowls of nuts,to be shelled.We always had plenty of them in the house.Then I remember the big news don’t eat nuts they’re bad for you,high in fat.

        • I am a guy with an interest in nutrition but with no vested interest in any drug companies, food industries or affiliations with any medical practices.

  11. No doubt your interpretation of these new findings are accurate as these studies predictably over-simplify the complex variables. And I am in no way a militant vegan or a vegan at all BUT I can’t ignore the larger picture of the toll meat production is playing in our current climate crises. Can we continue to pursue the optimal diet in a vacuum? at the risk of losing our life sustaining environment? What is a pro-paleo response to the inconvenient truth that meat production industry (as it necessarily exists to satisfy demand) has blood on its hands?
    I cant help thinking that some slap down, however inaccurate, might have a beneficial outcome.

    • Stop buying from the meat industry, buy from your local rancher or Weston Price organic producer. Read Alan Savory’s thoughts on how intense grazing IMPROVES the sustainability of the environment and water. I guess between a cow ruining the environment or a human ruining the environment I know which I’m more worried about. In fact I’d say its the human that ruined the cow and everything around it.

    • The influences that have led organizations like the UN and WHO to propulgate the fallacies of human-caused climate change and the immorality of the grassland-cow-man food chain are obviously self-serving interests which ignore the fact that God and nature are in control. The WHO report made me ask myself, which is worse, the woodland-deer-hunter food chain or the grassland-cow-man food chain. I concluded the answer is neither, since God created the prairies which supported the buffalo which supported the Native Americans for centuries. The white man just substituted the cow for the buffalo. At the end of the day, Nature (for those who chose not to give the Good Lord the credit directly), corrects itself and keeps things in balance. I trust in that, much more than the arrogance mankind displays in thinking he can unravel such a wonderfully complex Creation. So I say, which respect to diets, “To each his own, with moderation and variation for all!”

    • Joel Salatin has talked a lot about this also, in his articles and lectures. Here is one article:

      A quote from the above article:

      “There’s no system in nature that does not have an animal component as a recycling agent. Doesn’t exist. Fruits and vegetables do best if there is some animal component with them—chickens or a side shed with rabbits. Manure is magic.

      Historically, herbivores—beef, lamb, goat—were every man’s meat because they could be raised on perennials.”

    • Many things that are posted on nutritionfacts.org are very dogmatic towards veganism, that’s why I actually don’t read or watch that stuff anymore. For example comparing meat etc with vegetables only covering saturated fats, cholesterol and a view vitamins, excluding b-vitamins, amino-profiles and other important things. Aswell as never covering lifestyle factors (at least I can’t remember it being included) like they do here – see this article with the tendencies of red meat eaters (smoking, alcohol, no movement,…) and studies not being able to explicitly point out the meat as being the main reason. And the overall belief that “one-size-fits-all”, meaning everybody should go vegetarian or vegan because it’s the best – which obviously isn’t true and excludes again important factos: season, genetics, origin, stress tolerance, stress amount, amount of exercise and other things. You may experienced yourself that your nutritional needs not only change with season (winter/summer – cold/warm weather), but also with age (baby, childhood, teenager, adult, elderly) and sometimes you want to eat more meat, sometimes less. Paul Chek makes some great points on nutrition aswell.

      Also, besides scientific studies and whatnot, you just have to look at our ancestors of whom many ate meat frequently (and actually did smoke, drugs and alcohol – though very infrequently and they had a very different quality) and they didn’t even knew about cancer – which, along with other “modern world diseases” came as soon as people started eating white flour, sugar, very processed food, drinking more alcohol, smoking more and things of that nature, along with all the chemicals.

      Though, what I miss in this article is the differentiation between organic and non-organic – which will obviously make a significant difference aswell.

      • I don’t think the difference between organic/non-organic or grass-fed/CAFO has much bearing in large epidemiological studies, because there aren’t sufficient numbers of people consuming organic/grass-fed meats exclusively to be able to make such a comparison.

        That said, I obviously think it makes a difference and I’ve written about that before: http://chriskresser.com/why-grass-fed-trumps-grain-fed/

    • Dr. Gregor is a militant vegan and all of his research suffers from confirmation bias. Meat is the cause of all illness in his view.

      • From a spiritual perspective, which I realize is not the topic of this article or any article in the “paleosphere”, consumption of meat is more likely to cause disease indirectly. We inject unnecessary suffering, sickness, and premature death into the world through our farming system and it comes back to us. This is simply how nature works. If we want to stop experiencing those things we need to stop putting them into the world ourselves. It takes more willpower and knowledge, but it is certainly possible to thrive on a plant-based diet, and a mass shift toward that would be a worthy experiment for humanity.

  12. That the Paleo diet is better than SAD is not saying much. There are better ways for humans to eat than either diet and that is proven in the five Blue Zones….especially in Okinawa where the young people are going more Western and so is the disease rate…
    Good animal protein in limited quantities has benefits but that is neither the quality nor the quantity that Paleo or SAD consumes. It is easier in the US to be almost vegan than to search for good aniimal protein. However, vegan also needs to be described at length and the only thing I will say here is concentrate on whole plant-based products and get most of your fat from nuts, seeds, avocadoes and olives.

  13. Great article, Chris. We need more common sense in science in the news.

    The article in the news is entirely speculation about some other studies, some of which are random controlled trials, but which have problems with the controls. Most of the studies referred to in that article, however, are observational, including meta-analyses which often mingle observational with experimental evidence (as well as apples with oranges). You can’t make recommendations based on observational data. If you do, you have to add two other recommendations, e.g. if you recommend that people should avoid obesity to avoid diabetes, then you also have to recommend that people with diabetes should avoid obesity, and that people in either/both categories probably have to avoid something else, as yet untested, that may be causing both.

    There is also the problem with “red meat” because it avoids testing the effect of the quality of the meat. Organically raised beef doesn’t have the pesticide load that beef raised on GMO food has. No matter how much fat the animal has, pesticides will be attracted to it and won’t break down very easily. They do not have to reach the stomach, either to be absorbed, since they can get directly into the body through the gingiva. If viruses and bacteria can do it, so can almost any chemical you eat or drink.

    The status of the bodies of the people in these studies is never tested for toxin load.

    Many years ago, the processed meat industry was chastised for using nitrosamines and similar cancer-causing chemicals as preservatives. It was found out that just adding citric acid to the meat helped break down the nitrosamines in our guts to harmless molecules. Most processors, but not all, add citric acid. However, many researchers just look at the ingredients in an item to be considered, and not what actually happens to those ingredients in real people.

    Take the criticism of grilled meat. Many researchers seem to forget about the high citric acid content of barbecue sauce when they say charred meat is dangerous, lumping together all meat that might get charred.

    They jump to conclusions about safety (e.g. arsenic in apricot pits) without doing any tests in a real environment. Now, it seems that the National Cancer Institute, desperate to find a cure for cancer because of its complete failure in that realm, are turning to laetrile (in apricot pits), despite their criticism of people running to Mexico to get it in years past.

    • Thank you Chris for this very timely articl. I’ve been hearing about a book called proteinaholic just this week and thinking about studying the research behind it after eating proteins and healthy fats successfully for five years. I am tending my gut biomedical with homemade kefir and eating fresh fruits and veges, too. So you dispelled my confusion with this article. Thank you.

    • Common sense found in well rounded conclusions always disappears in these types of study reviews.

      It’s maddening as people continue to lean into higher grin consumption and an unbalanced diet higher in carbs/sugar because meat is “unhealthy”.

      Thank you Martha for the citric acid info!

  14. I was making a ‘blt’ today with uncured bacon, organic tomatoes, baby kale, avocado mayo, and fresh avocado in a chia wrap. My roommate saw the bacon and said ‘they just found out processed and red meats cause cancer’. I explained most of the ‘studies’ involve a set up something like this: obese people eating meat lovers pizza, and researchers concluding it was the meat and nothing else that must be the culprit of their health issues.

  15. We – the people seeking good health – need to be more concerned about the research methods than the persuasion of the arguments. Case studies are just that – particular cases. Surveys are strife with placebos. And researchers themselves go into experiments with their own biases. It will never be full proof.

  16. Will you ever get it? Living is dangerous to your health, and sitting on your duff at the computer, watching Tv and gorging on potato chips, dip, pizza, and McNuggets will only accelerate you ultimate demise. Oh, you’ll get adult onset diabetes b4 that final day comes.
    There is Nothing wrong with food, there is however, a mountain of wrong with how you process it because of your lazy western lifestyle.
    Meat causing cancer is as preposterous as the naive people that buy into the stupidity of such a conclusion.
    I’m sure you remember when butter and eggs were the incarnation of the devil.
    Go on a 100 mile bike ride or 20 mile road run, you’ll then have a new appreciation of the true function of food, and so will your metabolism.
    Can’t run, can’t bike you say, exercise is too hard?
    “Argue for your limitations and they’re yours”

    Politically incorrect (but it doesn’t change reality)

    • Gee, I wish I had time to go on a bike ride in my lazy western lifestyle…I guess I’m too busy hand pulling weeds out of a thousand acres so us lazy westerners can have an organic crop. Then growing a two acre garden and freezing and canning as much in my “free time”. And then in the winter I’m lazing around on my butt shoveling snow, fixing tractors and so forth. I wish I had time to prance around in tights.

      • I don’t think the comment is meant to actually someone like you, but the typical American in general…..you’re far from that.

    • Exercising till you are blue in the face does not make up for diet. Studies have proven that in many ways and you might also look up Dr Fixx, the marathon runner that died of a heart attack at an early age due to clogged arteries according to the autopsy report.
      Consuming a whole plant-based diet has been shown to be better for your body than many hours of weekly exercise.