Image Credit: Leboul99 / Wikimedia Commons. This image has been modified.

Harvard’s Meat & Mortality Studies

On Monday, the results of two major Harvard studies were published, following more than 100,000 men and women—and their diets—for up to 22 years. They found that red meat consumption was associated with living a significantly shorter life—increased cancer mortality, increased heart disease mortality, and increased overall mortality. The studies were featured in the video-of-the-day yesterday, Harvard’s Meat & Mortality Studies.

The American Meat Institute immediately sent out a press release: “A new study in today’s Archives of Internal Medicine tries to predict the future risk of death from cancer or cardiovascular disease by relying on notoriously unreliable self-reporting about what was eaten and obtuse methods to apply statistical analysis to the data.” Alas, yes, the Harvard researchers were not telepathic and did indeed have to ask people what they were eating. The Meat Institute criticized the esteemed researchers for using “survey data – not test tubes, microscopes or lab measurements….” No beakers either, I bet! Nor sizzling electric arcs, nor panels with pretty flashing lights. No, just cutting edge epidemiological science, however “obtuse” this may be to the American Meat Institute.

The Meat Institute asserted that “nutrition decisions should be based on the total body of evidence, not on single studies….” If two prospective cohort studies—the gold standard of observational studies—following more than 100,000 people for two decades published by one of the most prestigious institutions in the world isn’t good enough for the Meat Institute, how about the largest such study ever—the NIH-AARP study, “Meat Intake and Mortality: A Prospective Study of Over Half a Million People.” What does the largest forward-looking study on diet and disease in human history have to say on the subject? Watch Meat & Mortality for a distinct sense of déjà vu.

I think the most interesting finding in the new Harvard studies is that even after factoring out known contributors of disease, such as saturated fat and cholesterol, they still found increased mortality risk, raising the question: what exactly is in the meat that is so significantly increasing cancer death rates, heart disease, and shortening people’s lives? A few possibilities include heme ironnitrosamines, biogenic amines, advanced glycation end products, arachidonic acid, steroids, toxic metals, drug residues, viruses, heterocyclic amines, PCBs, dioxins, and other industrial pollutants.

Michael Greger, M.D.


Michael Greger M.D., FACLM

Michael Greger, M.D. FACLM, is a physician, New York Times bestselling author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous "meat defamation" trial.

16 responses to “Harvard’s Meat & Mortality Studies

Comment Etiquette

On, you'll find a vibrant community of nutrition enthusiasts, health professionals, and many knowledgeable users seeking to discover the healthiest diet to eat for themselves and their families. As always, our goal is to foster conversations that are insightful, engaging, and most of all, helpful – from the nutrition beginners to the experts in our community.

To do this we need your help, so here are some basic guidelines to get you started.

The Short List

To help maintain and foster a welcoming atmosphere in our comments, please refrain from rude comments, name-calling, and responding to posts that break the rules (see our full Community Guidelines for more details). We will remove any posts in violation of our rules when we see it, which will, unfortunately, include any nicer comments that may have been made in response.

Be respectful and help out our staff and volunteer health supporters by actively not replying to comments that are breaking the rules. Instead, please flag or report them by submitting a ticket to our help desk. is made up of an incredible staff and many dedicated volunteers that work hard to ensure that the comments section runs smoothly and we spend a great deal of time reading comments from our community members.

Have a correction or suggestion for video or blog? Please contact us to let us know. Submitting a correction this way will result in a quicker fix than commenting on a thread with a suggestion or correction.

View the Full Community Guidelines

  1. How about added phosphates and bisphenol-A in processed meat? Plastic wraps of processed meat might be a source of BPA.

    When you eat meat you miss a fish meal. This might be a question of trade off. More you meat, less you eat fish (or seafood or vegetable dishes).

    1. Fish is the most contaminated food in the meat industry. Pesticides like DDT, drug residues, heavy metals and other pollutants have all been found in fish.

      Processed meats are pretty bad too, the nitrosamines that are formed are highly carcinogenic.

      We should avoid these foods entirely, there is no nutrient we need from these foods that we can’t get from plants (except vitamin b12 which we should supplement).

    2. Then, the processed part should be blamed, not the meat itself. Remove all contaminants, feed the beasts correctly, avoid additives, avoid cooking methods that generates carcinogens, and then, redo the study. My suggestion.

  2. I came across this article and study and thought the good Doctor would have some thoughts on this. It sounds plausible the further humans moved away from the equator or to higher altitudes, but not sure eating meat gave or took life expectancy at the cost of enabling exploration.

    Eating meat helped early humans reproduce, spread around the globe,0,2388092.story

    1. This is one of the several theories of the evolutionary development of the human brain. The other theory which is also plausible is that humans were able to digest complex carbohydrates (unlike our primate cousins). Carbohydrates are pure energy and our brain requires 20% of total body energy to process. The starch theory is more plausible to me than the meat theory, since we process protein to energy much more inefficiently. The other theory which is also plausible is that we discovered cooking and were able to eat larger amounts of food since cooked food is basically predigested food. No one theory has been proven the victor, and there is still much debate on these topics. As of right now, we have no dietary need for animal products and since we have an epidemic of chronic diseases, it is best to avoid these products.

      1. ” As of right now, we have no dietary need for animal products.”
        This is untrue. Please provide your evidence that humans live BEST without any animal products. 

        What humans don’t need is carbohydrate:

        “The lower limit of dietary carbohydrate compatible with life apparently is zero, provided that adequate amounts of protein and fat are consumed.”

  3. Association is not causation. Let’s not forget that people. Eating meat does not cause cancer. It is not the meat itself and the Harvard papers absolutely do not indicate such. 

    And saturated fat is NOT a known cause of disease – please read this paper: 

    “A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD.”

    This is a good one too: 

  4. Dr. Greger, if someone was to have a plant-based diet with only limited amounts of meat (dominantly lean fish, chicken, wild game), do you think that it’s possible to see greater health and longevity compared to vegans/vegetarians? I work in geriatrics and see how valuable muscle tissue becomes in those later years which leads me to believe that accretion and maintenance of the most muscle tissue we can throughout life should help with both health, longevity, and functional capacity later in life.

    1. In my opinion it is all about risk. Eating small amounts of meat is better then eating larger amounts. Given current science relating to health there is no good reason to consume animal products as long as you can get adequate calories from a varied whole plant diet. The science supports that it is the best way to eat… along with maintaining adequate Vitamin B12 intake… see video series running from 2/3/12 to 2/912… to delay death and avoid disability thereby leading a quality life. Fiber is especially important in our diets at all ages and there is non in animal products. Maintaining muscle mass is best done by exercise. Fitness aka aerobic, flexibility, strength, balance and stability are important at all ages.

      1. “as long as you can get adequate calories from a varied whole plant diet.”

        That is the key point. In geriatrics, sometimes it’s hard enough to get them to eat anything. For them, meat appears to get the most ‘bang for buck’.

        I’m not a believer in total meat avoidance in the diet but focusing on a plant-based diet is definitely something I promote! And ideally the meat is either raised on a small farm and grass fed or wild game.

Leave a Reply

Your email address will not be published. Required fields are marked *

Pin It on Pinterest

Share This