Doctor's Note

So rarely are popular press diet books afforded such fact-checking. Kudos to these researchers. If only we had this 13 years ago when the book was on the bestseller list!

I have a few videos on popular diets, such as:

I also wrote a book about low-carb diets, which is now available free online full-text at

Unfortunately, nutrition illiteracy is not just a problem among the public, but among the medical profession:

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  • Astrofyziky

    There are too many claims out there stating to be pure scientific fact, but in all actuality they’re nothing more than pseudoscience. I’m delighted to see a video like this, and I believe more people need to remain incredulous of claims that don’t cite any peer-reviewed science. Keep up the good work, Michael.

    • E Cummings

      I agree. I wish someone would review Hyman’s Blood-Sugar Solution 10-Day Detox. In many ways, the approach seems sound (functional medicine, lots of whole-foods fiber, and even vegan-options for meals); I am wondering specifically about the use of the various supplements–esp. PGX–and the quantity of soy per day for well beyond the 10 days (90 days is recommended as a next step, I’m pretty sure.).

      • Yup. I see it’s time for Dr. Greger to debunk Dr. Hyman, too.

        Hint: Drs selling supplements generally have a vested interest that call into question their objectivity.

    • Scot Lyf

      And mind you, even peer reviewed science is contradictory depending on the scope of the analyses.
      Peer reviewed science is all over the board with conflicting conclusions in regards to diet.

    • Scot Lyf

      Even with peer reviewed science, conclusions on much of dietary matters are contradictory, due to different scopes of analyses. Your body reveals. Be mindful of what your body indicates with the dynamics of living throughout your life and the environment you live in,… and the lifestyle you have.

  • Felix

    Debunking diet claims is so typical for B bloodtypes. :D

  • Tobias Brown

    The battle against misinformation seems to be daunting, maybe even as large as the battle against the standard american diet. I participate in Quora and my goodness are there’s some adamant and active Paleo people there. It stresses me out to do battle with them.

    • The First Amendment can sometimes be a real inconvenience to actual evidence. I feel your pain.

  • Rudy

    I’ve always believed that we’re much more similar than we are different. We produce the same digestive enzymes, need the same nutrients and replace the same cells as they wear out. Scientists have found that our needs for each nutrient falls along a narrow bell-shaped curve. According to the blood-type diet, I should be eating lots of meat- and I used to. The result was that I was 20 pounds overweight; my joints ached; I slept poorly; was often depressed and had a poor memory. Then about 12 years ago, after seeing a book in the library by John McDougall, I went on a plant-based diet. The weight fell off me effortlessly, I now get a good 7 or 8 hours of solid uninterrupted sleep; I find myself feeling cheerful for no particular reason and my memory is just as good as it was 40 years ago. As far as I’m concerned, we’re all need to be on a type-P diet; P for plants.

    • Kitty

      I like Dr McDougall as well, my stumbling block to becoming vegetarian is my family even though I don’t live with them anymore they tend to talk down vegetarian life style.. like it’s some sort of bad thing.

      • Kitty

        I also have trouble with the plant based diet as well as I get very sick when I do a plant based diet so.. I can see there concern

  • Broccoli

    The Paleo Diet™ (yes, it is trademarked) and Blood type diets are funny. People actually believed that? Over 7 million books sold, maybe at $25 each, that is about:


    Maybe they have a “1 year membership, save over *add % here*”, about $50 per year. Maybe 7m people buy that too and that maybe equals to:

    $350,000,000 + 175m =
    over $500,000,000 …maybe


    Profits, just profits. $$$$$$$$$$ money money money.

    “His arguments sound scientific and he uses lots of big words”
    Totally agree, I see this on TV too.

  • Rivka Freeman

    Dr Greger @nutrition_facts: Any wise nutritionist knows maintaining blood sugar in a favorable therapeutic Zone is primary. All of you vegan vegetarian pushers like eat way too many high glycemic carbs to keep blood sugar stable. I think the reason you guys don’t get diabetes is cause you haven’t had a trauma or chronic stress or some physical condition that uses up all your stores of ascorbate. The purpose of the Blood Type diet is to use it as a method to identify foods that are personally intolerable, foods that cause of autoimmune dysregulation, foods that cause unstable blood sugar. Be careful how you speak about our nutrition minded colleagues like Dr D’Adamo. warns you: Never ever speak about in the same sentence as Atkins ever again because Zone Science rules; the Zone Diet can be done Vegan Vegetarian and it’s the key to healing, living and winning!

    • Ninobur

      I love being an American. We are free to believe the darnedest things. Too bad that some of these beliefs may hasten an early death.

      • Rivka Freeman

        Being in the Zone is the way to live forever with Moshiach!

    • Wade

      Blood sugar is held stable in healthy people by the pancreas producing insulin. The reason we vegans don’t get diabetes (T2) is we don’t accumulate excess intramyocellular lipids, thanks to our diets.

    • molecular bio

      I’m confused rivka…are you implying that ascorbate deficiency results in diabetes? Ascorbate is essentially a Vit C salt – very easy to remedy a deficiency if you eat a plant based diet or take a vit c supplement. But, just for argument’s sake, if vegan/vegetarians Don’t get diabetes, and if ascorbate deficiency is the cause of diabetes (which it isn’t), why not choose to just supplement ascorbate vs follow some whole diet that has been scientifically proven to cause pretty much all the major diseases of today?

      • Jason

        I could be wrong but it seems like a person wold have to try very hard to be deficient in ascorbate on a WFPB diet.

      • Rivka Freeman

        Hey Molecular Bio thanks for asking. Diabetes expresses or manifests (people get diagnosed) when they experience trauma, stress or they chronically eat too much high glycemic carbs that cause reactive hypoglycemia and rebound cortisol production. I equate adrenal stress and cortisol production with not enough ascorbate. Check out the ascorbate flush protocol cause adequate ascorbate keeps the adrenals from freaking out and burning out. I think Dr Greger and Dr Barnard eat enough plant based foods and have ascorbate stores. Hope they don’t experience traumas, like death of a child or getting cancer, or chronic stress like not having a job or money or enough donations. I don’t think it’s possible for me to just eat Vegan and be ok. I am not giving up medical nutrition therapy cause they dump extra Chemtrails here in the Jewish part of Brooklyn. I could identify who needs ascorbate based on blood test results and I would recommend adequate ascorbate, and to minimize insulin resistance I hold by Dr Sears and recommend adequate omega 3 for someone with a family history of diabetes along with unlimited low carb vegetables and measured amounts of high glycemic carbs.

        • ghostu

          Wow, chemtrails. You accept health nonsense about diet because you accept health nonsense connected with political conspiracy, the sort that strongly suggests scientific ignorance or deep willingness to shove it out of the way when it intrudes on the fear-and-oppression ordered part of your worldview. You accept the BT diet and go to extra lengths to try to justify it in the face of contradictory evidence because you are quite light on science to begin with. You pick what is sensational and what may otherwise make you feel more comfortable with yourself perhaps a bit too often; I’d say that instead you should be trying harder to have a view of science that doesn’t require special pleading to get around a rather mundane physical explanation.

          • Rivka Freeman

            If you got breast cancer at age 25 from taking Pathmark synthetic Vitamin E 15,000IU you would have a fear-and oppression world view too ghostu.
            I don’t see why we need to find beneficial outcomes in a population when this way of categorizing foods is for individualized use. The BT diet may be valuable for someone with MS or allergies that are impossible. What is wrong with thinking there is something to be gained from every one and every thing?

            I am little light on science, I don’t make up anything by myself; that’s.why I contribute $500 a month to I’m planning on asking some baseball players for a few mil soon so I can give at least $5,000 a month.
            Actually I love attention from you. I read this comment every day since you wrote it. You make me lol, Ha Ha Ha. It feels great to laugh. There’s a song I want to play for you but I don’t know how. It’s called “SHE DRIVES ME CRAZY” by Fine Young Cannibals. Ha ha ha!

        • Timar

          I agree with ghostu. I don’t think it makes much sense trying to rationally discuss nutrition with someone who believes in such utter BS as chemtrails. No offense, just experience.

          There seems to be a large audience for both nutritional information and all sorts of health-related conspiracy theories and FUD which is very profitably fostered by popular quack sites likes Natural News or Mercola. I think it’s the information overload many people can’t handle and fall prey to paranoia.

          • Rivka Freeman

            Here is a link to my teacher Dr Russell Blaylock MD from Mobile, Alabama. We had him in Clinical Nutrition Certification Class at about isolated soy protein is an excitotoxin! This link is a Dr Blaylock interview with visuals explaining every health risk from #Chemtrails and what they do to your brain.
            If this link doesn’t work, I’m sending it to too.

          • Rivka Freeman

            Wow I missed your dis to the Health Ranger and Mercola. Why do you think they are quacks? Oh right I’m the wise person who can learn from everyone and everything. What is FUD please? I really hate that you think chemtrails is nothing; breathing and topical exposure to aluminum dust is absolutely a health risk.

          • jazzfeed

            You just walk in the door with a preconclusion that chemtrails are “utter BS”. Why, because you have “experience”? Experience in what? Perhaps you’ve jumped into your private jet when you saw a chemtrail, flew up there and observed that, Hey, they’re only contrails, there are no chemtrails, it’s just water vapor! Is that how you “know” with such conviction that in fact there is no aluminum, barium, etc fallout? No? How else do you know? Maybe you “know” because you believe that all “conspiracy theories” are only speculation and you’ve never actually tipped your head up to look? Newsflash: Many former speculations that were derogatorily called You just walk in the door with a preconclusion that chemtrails are “utter BS”. Why, because you have “experience”? Experience in what? Perhaps you’ve jumped into your private jet when you saw a chemtrail, flew up there and observed that, Hey, they’re only contrails! There are no chemtrails, it’s just water vapor. Is that how you “know” with such conviction that in fact there is no aluminum, barium, etc fallout? No? How else do you know? Maybe you “know” because you believe that all “conspiracy theories” are only speculation? In any case, many contradict you and they’re very diverse and bright. Links at your request.
            I’ve read Mercola’s site for 15 years, NN almost as long. There is absolutely no sense whatsoever to your quack comment. There are thousands of pages of information on both sites, MASSIVELY REFERENCED with links. On these videos , the references fly by and you’d have to keep your finger on the pause button to even have a chance to get the reference if you’d like to verify it yourself. At Mercola, there are hundreds of interviews with all manner of doctors and working scientists. There is a robust forum where I’ve learned even more.

            But then you state that people could fall prey to paranoia because of information overload. These are two separate issues, quackery and overload. With these two adjectives you’ve evoked four categories: quack sites with too much info; credible sites with too much info; quack sites with succinct info; and credible sites with succinct info.

            I’ve read Mercola’s site for 15 years, NN almost as long. There is absolutely no sense whatsoever to your quack comment. There are thousands of pages of information on both sites, MASSIVELY REFERENCED with links. On these videos, the references fly by and you’d have to keep your finger on the pause button or play it over and over to even have a chance of getting the reference if you’d like to verify it yourself. At Mercola, there are hundreds of interviews with all manner of doctors and working scientists. There is also a robust forum where I’ve learned even more from dedicated health enthusiasts.

            But then you state that people could fall prey to paranoia because of information overload. These are two separate issues, quackery and overload. With these 2 adjectives you’ve evoked 4 categories: 1) quack sites with too much info; 2) credible sites with too much info; 3) quack sites with limited or succinct info; and 4) credible sites with limted or succinct info. The apparent false implication is that only categories 1 and 4 have any members.

        • Last photo I saw of Dr. Sears, he looked pretty obe…I mean, insulin resistant to me.

          • Rivka Freeman

            That’s cause Dr Sears likes a whole egg with many egg whites omeletes every morning. Maybe I should forward him some of Dr Greger’s videos about eggs. He may not look good but he is brilliant and practical. Dr Sears worked for Upjohn and told them to give it up cause no one will want injections to lose weight. His therapeutic Zone Diet deserves as much respect as we all give Dr Greger and

      • Rivka Freeman

        You know what Molecular Bio: Ascorbate deficiency might not always cause diabetes, but ascorbate deficiency makes my ear nose and throat mucus membranes itch and taking an adequate amount helps me stop asthma. Ever hear of ascorbate flush protocol by Dr Russell Jaffe? That’s how you figure out how much ascorbate is appropriate for your needs.

    • Darryl

      Diabetes appears to be a natural consequence of lipid accumulation impairing muscular/adipose cell insulin sensitivity, followed by glucolipotoxicity to pancreatic beta cells. I discussed relevant reviews and diet trials here.

      You won’t find much diabetes among East Asians eating their traditional diet white rice, Native Americans eating corn, peoples of the Andes eating potatoes, Polynesians eating breadfruit and taro etc. Diabetes in ancient times was a disease of those eating like royalty, and in modern times a disease of those eating like ancient royalty.

      • Thea

        Darryl: Thanks for the reply and the links to those video clips. I’m a big fan of Jeff Novick and hadn’t seen those clips.

      • Rivka Freeman

        Jeff Novick on C R A P = Calorie Rich and Processed

      • Rivka Freeman

        The Zone Diet is carbohydrate, protein and fat balanced and appropriate. Eating a vegetarian diet will not be too high protein. And everyone better keep the starches limited cause you just can’t keep your blood sugar in the therapeutic zone if you eat high glycemic carbs in abundance even if they are whole grain and loaded with fiber. Forgive Dr Sears for acting like a doctor and telling people how to control blood sugar even when they eat CRAP Calorie rich and processed!

    • Timar

      Here’s the catch: high glycemic load diets promote diebetes, but so do high animal protein diets, and so does caloric overload. Hence, the SAD, combining all three attributes, seems like an experimental diet designed to promote diabetes. Sadly it isn’t. It is the SAD.

      Most traditional diets which rely on high glycemic index starches, like white rice or corn tortillas, use them in a way which minimizes their impact on blood glucose: they are always eaten together with plenty of vegetables, herbs and spices which provide fiber, acidity and phytonutrients slowing down the digestion of the starches and counteracting the adverse effects of high blood glucose.

      Stop eating refined and manufactured junk food, avoid sweetened beverages, limit your intake of animal protein (to no more than 20 g/day), eat plenty of vegetables, fruits, legumes, herbs and spices and you don’t have to worry about diabetes even if you eat some high glycemic starches as part of your meals.

      • Rivka Freeman


    • Neal Barnard looks real diabetic, doesn’t he. Not.

      Suggest you ingest some real science besides the Glycemic Index which, BTW, was invented by a vegan.

      How to Become Insulin Resistant ( The Paleo Way) [or The Zone Way, if you prefer]

      Part 1

      Part 2

      The way to rehabilitate a broken carbohydrate metabolism is with healthy unprocessed carbs.

    • Kitty

      Carbs are a problem for me, I find a meat based diet keeps me balanced and not hungry for long time I can go almost all day without needing food and have a stable blood sugar. I tried the plant base diet and got very sick with colic. it was aweful and painful.

      • Sounds like you need to soak those grains, beans, nuts and seeds for at least 12 – 24 hours in order to indulge in those plant based foods. There are really good instructions at Traditional Cooking School with #AskWardee if you want to try again to incorporate these. But root vegetables provide great resistant starch, potatoes beets, squash are good carbs that are much easier on the digestion. Going all day without food probably does cause you to produce cortisol stress hormone that makes your liver release the stored glycogen. You definitely need antioxidants from some plants foods fruits to counter animal food toxins.

  • Chessie

    No kidding.

  • Steve

    The notion that a single genetic factor would be determinative of something so complex and varied as digestion and nutritional requirements never made sense. More broadly, body typing systems in general (think Mercola) are similarly doubtful guides for nutrition.

  • Steve

    Question for the Doctor: Do you have any information on the diet supplement called Gardinia Cambogia? Thans.

    • Jean
      • Steve

        Thanks for sharing that Jean. I think I’ll throw the product in the trash after reading that.

        • jazzfeed

          I would read further first. Do not trust Wikipedia for any entry that has money tied to it. It is manipulated.

  • Thank you for this video. “Dr” D’adamo practiced in Portsmouth, NH several years ago. I am not sure if he is still there or not. My good friend is a nurse and used to work for this quack. He had her on over 20 supplements all of which HE sold in his vitamin shop. She was on this crazy diet and I remember her saying she couldn’t eat blueberries! I am blood type O so she told me I had to eat lots of meat. I told her “No, I don’t think so”! I have been vegan over 13 years and I am thriving. All my blood work is perfect, I have a ton of energy and feel great. My friend thought this “Doctor” was great. Thankfully she no longer works for him.

    • jennyb

      You are not talking about Peter D’Adamo! He is the person who wrote the blood type diet book mentioned here. Who you are referring to is his father, who is a respected naturopath, not only here but in Canada and Europe as well. Both son and father do not share the same ideologies, However, I just want to point out that unless you have treated over 60,000 patients and gotten good results in healing these patients for years, you have no right to judge anyone!

      • I am talking about the one who wrote the book.

  • Guest

    It is a shame when people “review” a diet they don’t take the time to look properly into it, merely reading the first book on the topic, which was merely an introduction, and looking at the millions of testimonials. And what about the fact that A’s don’t produced much stomach acid (and so can’t handle fats and heavy protein), and O’s produce a lot (and so can digest meat)? Certainly fits perfectly for me (an A) and housemate (an O). There are at least aspect about BTD that are spot-on and v. useful to know. Please do your research more thoroughly people. Why assume everyone is out to get you or just sell you stuff? Why the personal putdowns without looking into the guy? That is such a negative viewpoint and childish behaviour. Dr D is dedicated to helping people! There are so many testimonials to support this!

    • I tried to delete this comment, but anyway repasted it below.

  • It is a shame when people “review” a diet they don’t take the time to
    look properly into it, merely reading the first book on the topic,
    which was merely an introduction, and without looking at the millions of
    testimonials? And what about the fact that A’s don’t produced much
    stomach acid (and so can’t handle fats and heavy protein), and O’s
    produce a lot (and so can digest meat)? Certainly fits perfectly for me
    (an A) and housemate (an O). There are at least aspect about BTD that
    are spot-on and v. useful to know. Please do your research more
    thoroughly people. Why assume everyone is out to get you or just sell
    you stuff? Why the personal putdowns without looking into the guy? That
    is such a negative viewpoint and childish behaviour. Dr D is dedicated
    to helping people! There are so many testimonials to support this!

    • Jason

      Based on you post I’m not sure what makes you think Dr. Gregger’s is not thorough or that he did not look properly into it. Did you click on the links provided so that you could check the resources he used to come to his conclusions?

      • I have been following D’Adamo and his work for 2 years and am in constant contact with people also following the diet. There is a lot to it. Not just the first book! People really don’t bother to do proper research bf. reviewing diets it seems.

    • Plantstrongdoc M.D.

      Testimonials are not science – could just be faith. Claiming that antigens of red blood cells has anything to do with acid production from parietal cells makes absolutely no sense. What about all the other systems RH, Kidd, Kell, Lutheran, MNS? Are they just ignored? Blood group phenotypes are messured in billions. Are there a billion different diets in the books? In my opinion this is not even pseudoscience – it is rubbish.

      • But you haven’t looked into the diet obviously! The diet is customised as much as pos for each individual based on genetics, secretor status, as well as blood type! Please research first.

        • Please watch Dr. Greger’s videos and follow his referenced links to the thoroughly done research into the diet before commenting.

          PS. I do understand it’s hard to admit being hoodwinked. Belief systems are intriguing phenomena.

      • Plus there are tons of testimonials and constantly pouring in, not just a few.

        • Steven Irizarry

          all of them are a result of placebos…a proven science

    • Sholeh

      My husband and I really got so much benefite from BT diet, Big Thanks to Dr. D!

    • JenniWest

      Debra…People are funny. They don’t wait for the “science” to go vegan. They don’t hesitate to eat garbage even though the “science” says it’s probably killing them. They don’t give a crap about the “science” behind the medications they take even though the side effects are horrendous and often a likely cause of death in many. But whoa…throw a diet at them and suddenly they are all about the science. Right.

      The thing about the Blood Type diet is that there IS science. A good deal of science that supports this way of eating. Dr D posts news articles seemingly monthly about nutrition “discoveries” that he’s been touting, based on science, for years. Even decades. I mean duh, humans can live on garbage for years, for God’s sake. This isn’t about living. This diet is about thriving and there are many people who, their entire lives, have never felt that good to even have a perspective on THRIVING.

      People are too lazy, too biased and too stupid to try this diet. If you want the science, STUDY IT. It’s there. Dr D makes it easy to find in his books, his footnotes and his website. If you want to sit in your nutrition armchair and throw blanket condemnations, fine! Do it! Nothing worthwhile in life is ever easy and it was a hard slog for me to finally find the blood type diet. I have a myriad of illnesses that are simply not part of my life anymore. I’ll end with a partial list of the things I no longer have:

      Heartburn and esophageal spasms where my next option was surgery. Heart palpitations with blood pressure spikes, gone. Vertigo. Symptoms of MS for which I was poked prodded, MRI’d, semi-diagnosed and sick of. Gone. Irritable bowel syndrome. Gone. Over 30 food allergies, no more symptoms. Asthma: I haven’t used my inhaler in 9 years. It keeps expiring. Athritis. OMG, where do I begin with my arthritis? A 45 yr old woman walking like a 90 year old. I would literally have been in a scooter by now at age 51 at the rate I was going. I followed Dr D’s arthritis recommendations to the letter and I am not just better, I am cured. I have never felt better in my life.

      All I had to do, you guys who want SCIENCE before you’ll even wipe your you-know-what, was change a few things on my shopping list. That’s it. Change a few things on my shopping list. DRASTIC, I know. The diet is free. They website is all you need. You don’t have to eliminate entire food groups. They help you with portions. They have recipe books if you aren’t creative.

      The only thing I can say to people who act like the noodges here: DUH! You are only hurting yourself with this zealot-like skepticism.

  • satch

    Does anyone know if the dried barley grass and dried wheat grass are digestible by humans? I know that the “juice” is fine, but how about the actual fiber of the grass? Was told that humans can not digest grass, only the juice, but who knows. Thanks, if anyone has any input on this.

    • Timar

      Human don’t have the digestive enzymes to break down the fiber polysaccharides in the grass (or any other plant food). Most herbivores don’t have these enzymes either. Ruminants rely on the help of bacteria in their rumen to digest the fiber and get energy from it. However, the fact that in contrast to a cow you hardly get any calories out of leafy greens doen’t make them less healthful, as they offer a wide array of minerals and phytonutrients. You just can’t thrive on greens alone, like ruminants do, but have to rely on starches, fats or protein to supply you with the necessary calories.

      Regarding grass: I think it is very chewy and tastes awful. So why bother with eating grass, when you can have delicous and equally nutritious leafy green vegetables like, say, arugula or spinach?

  • Nancy

    Great video, Dr. Greger. I knew the blood type diet had to be totally
    bogus. Now if there was only someone like you to help ferret out the
    lies in the skin & hair care industry. Oh wait. That would probably
    make most of the world economies collapse. We still need to prey on
    people in search of an anti-wrinkle cream purporting to be the fountain
    of youth in order to keep the economy going.

    • b00mer

      Have you heard of Paula Begoun? She has a free database called “beautypedia” with reviews for most skin care/makeup lines. Very objective criteria e.g. pH, appropriate packaging, active ingredient concentrations, lack or presence of both irritants and anti-irritants, product claims vs ingredients with peer-reviewed sources to back up her critiques. Very helpful. Also has a ingredient-specific database so you can look up any of those on their own. She is very upfront about certain things being absolutely impossible barring surgery or other procedures. I have always thought of her as the Dr. Greger of skincare. :)

      • The Dude

        Hardly so, Dr. Greger is not selling products it looks like Begone is… Was this a set up to get people to look at her site?

        • b00mer

          If you’re not interested in skincare, The Dude, don’t go to her site. Nancy very clearly expressed a request for thorough research and critiquing of skin care products and ingredients, and I provided a resource I find to be extremely informative and useful. I find her to be much like Dr. Greger in that she provides peer-reviewed journal articles and cuts through the generally baseless and preposterous claims that most skin-care companies make. If she doesn’t have a peer-reviewed journal article to cite in support of a claim, she doesn’t make it.

          I don’t recognize your username, but if you read the comments sections here often you would see that I am a frequent commenter, not a one-time spammer. Like everyone else here, I enjoy offering commentary and sharing links and resources that may be helpful to other members of the nutritionfacts community.

          Frankly if I limited myself to only offering resources from those plant-based diet advocates who don’t sell anything, I would have to refrain from sharing recommendations for the Esselstyns, McDougall, Barnard, Fuhrman, Novick, etc…

  • Debbie McNally

    My husband is a cab driver and is going to college online. We have been vegan for 2 years now. We have tried juicing for 26 days. We tried Dr. Fuhrman’s plan for 6 months. We don’t eat anything processed. I make everything from bread, pasta to Spaghetti sauce and vegetable broth. I even make all of our cleaning stuff and shampoo and body wash. We have a garden that is finally producing we have lettuce, squash, Chickpeas, and chiltepine. He eats about 1,000 calories a day. I dropped 50 lbs as soon as we went vegan. Erik has not lost any of his 300 lbs. He is getting very frustrated and depressed. We also had all his blood work done and the results were great. Please help. Thank you

    • Jason

      I could be wrong but it sounds like he is not consuming enough calories. Baring any medical condition that prevents him from loosing weight he should be able to consume 1600 kcal’s a day and still drop about 2 lbs. a week. If he exercises he would need to consume even more kcal’s. Check out It should be able to tell you how many calories he needs to consume daily in order to maintain his health while losing weight. Also, if you can afford it he may benefit from one of Dr. Mcdougal’s live in programs.

      • Debbie McNally

        Thank you for your help. We will try that idea. What medical conditions would prevent him from loosing weight?

        • Jason

          Well, I could not comment on that one with any authority. Not because I’m not aware of the illness but, it could be something really simple to something kind of scary and I don’t want you to worry needlessly. The right Doctor who practices lifestyle medicine (Dr. Mcdougal) could certainly help you.

          • Debbie McNally

            Jason I appreciate your help. This mystery is driving us crazy. Could you give me any ideas please. If we could afford to go to Dr. McDougall’s we would. The problem is that Erik sees me making everything myself and is frustrating that nothing is working. Knowing what we are working against would be a real relief.

          • Jason

            Debbie, I certainly would give you more information if I were qualified. If you search for illnesses that prevent weight loss on google you will come up with a list as long as your arm. In my opinion a list like this will not help point you in the right direction. Try searching your area for a healthcare provider that may be able to advise Erik much in the same way Dr. Mcdougal would. Here is the link where you can search for the closest health care professional in your area. Sorry I could not be of more help but I hope I have helped point you in the right direction.
            As I stated earlier I think the simplest thing to do would be to continue on the whole foods plant based diet and increase his calories to about 1600 per day. I understand how difficult it is to be active while carrying a full time job and school as I am currently in that boat my self. However, if Erik is able to find the time to engage in some moderate exercise it will probably help him with his weight loss goals and provide a positive way for him to relieve any mental stress he may be dealing with.
            Additionally, you may consider weather he is properly hydrated and resting sufficiently each night. I say all of this because stress can be a contributing factor to difficulty in weight loss.

          • Deb

            Please look into the effect stress has on our digestive hormones eg Gabriel Method

      • Scot Lyf

        A higher percentage of non starchy vegetables and fruits would be good, cooked and raw,… and some quality animal products. Be human,… fundamentally, for optimum health.

    • Thea

      Debbie: I had written out a nice long reply, but just before I sent it, I went back and more carefully read what you had written. I agree with Jason, 1000 calories sounds pretty low. I’m not a doctor or expert. I’m just going by what I have read about appropriate calorie amounts for adult men.

      One thing you may want to ask yourself: How sure are you about your husband’s calorie count? If your method of counting is off or if your husband is snacking at work, then getting too few calories may not be the issue. Just in case, I wanted to share with you part of the advice I had originally written. There is a free lecture on line called: “How To Lose Weight Without Losing Your Mind.” This is a talk from one of the experts from the documentary Forks Over Knives. It is an excellent talk and fun to listen to.
      Dr. Lisle explains how to get enough food to feel full, but still have less calories. This talk may truly be irrelevant for your situation, but you might want to at least check it out.

      Another thought: Even though McDougall’s program is too expensive (believe me, I get that!), I wonder if there is a local doctor who is actually knowledgeable about good nutrition and who might be able to see if anything unusual is going on with your husband medically?

      I wish I had more help for you. I think it is worth taking a moment to acknowledge the great accomplishments that you have made so far. It’s not easy to change your diet the way that you and your husband have. The first order of business is to stop and congratulate yourselves.

      Also, I wanted to let you know that you are not alone. Many people seem to lose all or most of their extra weight when they switch to a whole plant food based diet. But not everyone does. In my own family, there is a couple very much like you and your husband. The wife lost a ton of weight and the much more over-weight husband hasn’t lost a pound–but his blood work improved significantly without any drugs. Sound familiar? (But in that situation, I know the husband is still consuming too many calories. So, the situation may not be exactly the same.)

      You may not have reached all your goals, but you are totally on the right track. I feel like/hope you are both almost there. Please report back and let us know how it goes. We’ll be rooting for you.

    • Lawrence

      Debbie, I would like to add something to the excellent replies to your post. For a very small investment you may obtain Dr. McDougall’s wisdom and experience from this book:

      Also, Dr. McDougall has posted his program for free on his website:

      On a personal note, I have been vegan for going on three years and have really narrowed down my food choices to whole foods, using Dr. Greger’s website as the best resource for selecting the best foods for the best reasons. That said, I have lost a few pounds and my numbers have improved, however I am still overweight and the reason is simple: I take in too many calories. It’s a process for me and I won’t give up trying to find the balance point of good food and adequate nutrition. Your story is an inspiration. Keep going!

    • b00mer

      You could join Furhman’s or McDougall’s forums if you haven’t already. Furhman’s costs money, different costs for different “levels” of access to the forums and to him basically. Which kind of rubs me the wrong way, but anyway. McDougall’s on the other hand are free and in my experience much more active and interesting. Jeff Novick posts on there and replies to inquiries regularly. And he has a very ‘by the numbers’ take on nutrition. I would be interested to hear his take on your situation. Worth a shot.

    • Not everyone is suited to veganism! Ask him what foods he is drawn to perhaps, and it is so worth looking into BTD. :O)

      • Barking up the wrong tree again??

    • Rivka Freeman

      Sounds like he needs to move more to stimulate metabolism. Send me his blood tests, I am always able to find something wrong in blood test results. Email Rivka at

    • jj

      To few calories and the body goes into starvation mode and holds on to what its got. Hence weight stays on.

  • MJ

    Thank you for this.

  • The Blood Type Diet is not true? Shocking.

    • Do your own research people! It is v. good! :O)

  • dar

    FYI : the D’Adamo diet was based on/a rip-off of Ayurvedic medicine…pretty heavy stuff,indeed…compare this to the modern ‘scientific’/pHarma studies… [which we all know are legit]

  • Jen

    So sad, but the company I work for just started a weight-loss program completely based on this book. Last year it was Herbalife. I wish they would do some research before promoting these unhealthy programs to employees!

    • Thea

      Jen: I agree that it is really sad. I have a similar problem where I work.

      Here’s what I was thinking about a plus side for where you work: If they are willing to try all sorts of wacko programs, then they might be willing to try a real evidence-based program too. In other words, if they can’t distinguish a legitimate program from a bad one, they have no good reason to reject a legitimate one. So, *maybe*? after they get the blood-type program out of their system, you could convince them to look into the PRCM program for companies. (You can start by looking up the PCRM info on the Geiko study if you are interested.)

      Just a thought. I tried this where I worked and it didn’t fly. :-(

  • Peter D’Adamo

    Despite your rejoicing, the PLOS study on the Blood Type Diet was far from an adequate representation of the diets. You can see the problems with the study criteria here ( and a blog entry discussing the study’s severe shortcomings here (

    In essence, a look at the core data used in the PLOS Study debunking the Blood Type Diet (BTD) finds support for the researcher’s conclusions that if your experimental subjects eat potato chips, sandwiches, pizza, ‘beans,’ mac-and-cheese, French Fries and processed meat products while doing 13.7% of the Blood Type Diet, their final cardiometabolic markers will probably not vary much by blood type.

    • tedster

      Peter: I tried both links that you provided and neither one worked.

      • Merio

        i have the same problem…

        • Take the extra bracket off the end and the links work okay.

          • Merio

            thanks !

      • FB

        Look at the linked URLs – they each have an unnecessary parenthesis at the end. Remove those and the links work.

    • Dr. No

      Dr. D’Adamo:
      Let’s put the study aside for a minute. Do those patients who follow your type O diet have an increased risk of CVD/DM2? Or not? It is clear, based on the evidence, that animal foods (yes even organic, pasture raised etc) contribute to the aforementioned diseases, including cancer…. but I’m interested in your perspective.


      • Dr. No

        *Crickets chirping*

        Any thoughts, Dr. D’Adamo?

        • ghostu

          It should be fairly obvious that there’s a high likelihood that Pete was just here to drop a rhetoric bomb as a support for the dogmatically-driven true believers (possibly including himself) to keep believing. If Gregor’s point about the unfulfilled promises of Scientific Studies is true, then it shows the intellectual dishonesty at the root of the movement; in this case, the D’Adamo clan itself. If you make a public claim that you are conducting valid research and don’t follow up with at least an explanation of why the research failed to be as valid as you thought it would be, it’s hard to see how serious you are going to be in discussing information that may cast a disconfirming shadow over your theory.

    • God, looking at the study, they allowed biscuits, pizza, processed meats! etc How can you compare this study with BTD? The researchers didn’t even bother to study the diet properly to find out what it’s about before embarking on it! So annoying, waste of money and not helping the public! Makes you wonder if their motivation was “pure”!

  • SomeAngryCitizen

    This is bath salts not food you air heads.

  • I don’t know what anyone is talking about! Eat right for you blood type is real!!!!! Real I say. Must I say it again?
    Okay it is not real, LOL! I am Type O and I am supposed to do best on a meat diet. YEs, I a am primal man. I bang my chest with both hands. ME MAN! ME MAN! Bahahahahahaha. I eat a whole food plant-based diet, high in carbs, moderate in fat, and low in protein. I haven’t been sick in over 2 years since I adopted a plant based diet. I never though I would eat a plant-based diet, it is just something I happened upon. I have been cutting out meat in different points in my life, from pork to beef to poultry to fish. Each time I cut something out my body responded in a good way. I still got sick though, until I adopted a plant based diet. For my blood type I should be dead though. Good thing I didn’t listen to that blood type stuff.

    • You always get one… :O)

    • jj

      Another type O here. Am doing just fine on a whole foods plant based simply prepared way of eating. Much healthier than when on animal products.

  • Tom

    Response and explanation of the “study” done with the Blood
    Type Diet…They couldn’t even use 25% of each blood types neutral or beneficial foods :-(

  • CarrotBrocante

    Thanks for this video! I also read this book in the past and thought it was plausible.
    It would help a lot if you could also make a video and actually name some stuff he wrote which was just not scientific and untrue. Then I will transalte it and show people who believe him.

  • Kay

    I love when I see a Doctor do a report on another Doctor’s diet, and immediately following the report it says “I also wrote a book “click here.” So basically, Dr. Greger cherry picked articles against the BTD, just so he can get his name known…… Unreal….

    • Tommasina

      Hi Kay, I’m not sure if you watched this video, but the research stated in the video was the only scientific review of the evidence for the blood type diet. That’s not cherry picking, it’s using the only peer-reviewed research available. It sounds like you’re thinking Dr. Greger is advancing some sort of agenda?–maybe you didn’t see that his book on carbs is available for free, whereas the blood type diet book has sold 7 million copies. Dr. Greger founded under the belief that he would review the science and let people decide for themselves. I hope that clarifies the picture for you. :)

    • JacquieRN

      HI Kay, you may know this but in case you don’t: All speaking fees and proceeds Dr. Greger receives from the sale of his books and DVDs are all donated to charity. And the book, he mentions here is free to all.

  • Armando

    This is somewhat of an unrelated question and I do currently donate blood for purely altruistic reasons…but from strictly a health perspective…Regularly donating blood…Harmful?…Harmless?…or Helpful?

  • David Edsall

    As I’m currently researching this, and will read the book soon, I’d like to point one thing out. The research mentioned has the following conclusion:

    “Sixteen articles were identified from a total of 1415 screened references, with only one article that was considered eligible according to the selection criteria. The identified article studied the variation between LDL-cholesterol responses of different MNS blood types to a low-fat diet. However, the study did not directly answer the current question. No studies that showed the health effects of ABO blood type diets were identified.”

    “No evidence currently exists to validate the purported health benefits of blood type diets. To validate these claims, studies are required that compare the health outcomes between participants adhering to a particular blood type diet (experimental group) and participants continuing a standard diet (control group) within a particular blood type population.”

    The conclusion is that there is no study that has been done. Thus, there is no evidence pointing EITHER way.

    One trend that I see among many westerners is the quick jump on calling things pseudoscience when they don’t agree with it (take chiropractors or Chinese medicine for example).

    For something of this calibre, a long-term study, with many subjects, would have to be done in order to “prove” it through means of a study.

    I’m in no way saying the blood type diet is or is not valid. However, just as one shouldn’t jump on board and take it as truth, one should not instantly call it pseudoscience because they don’t agree with it.

    That being said, I’m glad to see this video out. It’s good to see the other side of the issue.

  • karl

    What is the expose for “Wheat Belly” in regards to gluten and GMO wheat?

    • Thea

      karl: Dr Greger will be releasing a series of video on gluten very soon for more info on this topic. (Keep an eye on the videos-of-the-day) In the mean time, check out this video, ”
      Alzheimer’s Disease: Grain Brain or Meathead?”

  • i hate videos


  • Mark Schroeder

    How is this article even remotely close to the blood type diet being debunked? You’re only advertising your preferred books. You’re not citing evidence gained from science, or the evidence gained from the science of others.

  • chris

    Dr. Greger didn’t mention even bigger figure among the blood type diet specialists, DDS. MS William Donald Kelley, which would contradict his ‘debunked’ message, even more. Some information about Kelley’s works can be found at: or even better in Ty Bollinger documentaries “The Truth about Cancer’, or in few of his own books. Since different blood types contain different antigens on their surface, frequently glycosylated (except for type O), their essence is related to the response of the immune system. Every bug in our guts reacts constantly with the surrounding load of nutrition, and sugars are the number one resource for them. So logically, it would make sense that our immune (through blood system connection) system can affect the digestion (in particular in case of leaky gut). Dr. Kelley healed himself and many, many patients applying his experience. So Dr. Greger, please take your Hitler comparisons, away when you talk about people who did great research while helping others. You certainly learned in the school, that Hitler was killing, not healing!!!

  • Most annoying voice and what sounds like envy.

  • Summit14

    I would like to get more information about Metabolic Balance developed by Dr. Funfack. Thanks

  • Links found between blood type and risk of cognitive decline

  • felicia

    Ok, I am doing a bit of research here. I know not much of the two topics but as I read all the comments here I couldn’t help but notice people mentioned eating large amounts of a certain food on the blood type diet. So I am confused because of this chart . It gives you a basic run down of foods good and bad. It never said to eat one thing over another except that leafy greens are very good for you and small portions of meat! I tend to agree with this and I have had a food sensitivity test done a year ago so, I was looking at the foods on this list to see how my personal allergies and sensitivities blend or don’t. I have sensitivities and allergies aligning with the avoid lists, but only one food type that is considered neutral. I can also eat some things on this avoid list that are not on my sensitivities list too.It sounds like a reasonable chart to me. I personally think if we were meant to be “veggies only” humans we would not need to consume or utilize b12. I know it can be consumed through earth but life can go unwell for many as soon as it runs low and it isn’t easily found in veggies sources. I don’t think people will want to have to be strategic about finding specific food sources. I do believe we all need to consume some small amount of meat. Fish has some of the best b12 sources and (red meat may give blood issues) but most fish do not. I am not the most religious person in the world but right now the words ( I will make you fishers of men ) comes to mind. So, is there a diet that consists of mostly raw vegetation and fish and if so where is this research? As far as grains go idk because we as humans today eat so much and it is processed whether its glutenous or not. should we for go them or just eat them whole if we cant digest something whole then we should not be eating it. what do you think? I know this is all over the place i a just thinking aloud looking for answers…

  • Nosteratella

    Loren Cordain, Ph.D., who wrote the first Paleo diet books and researched the topic through his post at Colorado State University, is a debunker of the blood type diet hoax. His article about it can be read here:

  • The topic of ABO blood type, disease prevalence and nutrition is more complex than this topic and thread portray:

  • James

    I need to eat meat because blood type tho

  • Tom Martens

    The science behind ERFYT

    on ‘first blood type”

    Some studies.

    First, different levels of

    Type A neutralizes IAP

    Response in humans is
    probably the same, but for example this would explain why people with less IAP
    benefit from lower fat diets

    If you get the gist, IAP
    works in conjunction with other things, such as enzyme CD36, to transfer fat
    across the mucosa. The thing is that what is being transferred can be different
    structures of protein, different lengths rather. In other words it decides what
    type of fat makes its way into the blood.

    See the link below and the
    quote from Dr. D:

  • Tom Martens
  • One day someone will find that there is more to the blood type diet than “meats the eye”… :-)

  • PlantSlantMan

    Been searching the web for some science related to the “Metabolic Typing Diet”.

    Can someone please let me know, if this has been debunked by science or is actually based on some kind of science?


    • payoung

      Hi, I did a quick search and was not able to find any peer reviewed studies either justifying or debunking diets based on metabolic typing. As the wikipedia article you referenced says, metabolic typing was first introduced by a dentist named William Kelley who was very controversial in regards to his claims of curing cancer with a dietary protocol that was based on metabolic typing. His work was later continued by the late Dr Nicholas Gonzales who was a Sloan Kettering trained immunologist (who’s books I have personally read) and who published several cases (albeit not in peer reviewed journals) where he treated cancer successfully using a dietary protocol that utilized the metabolic typing protocol that he says was passed on to him by Dr Kelley. Having looked into Dr Gonzales’ work, the thing that was always suspect for me was that he never revealed the full “secret” of the process he used to determine a person’s metabolic type, although he alluded to many aspects of it in his writings. His protocols also used a very large amount of dietary supplements which were of sold through or by him to his patients. Dr Gonzales died unexpectedly last year and to my knowledge his practice in New York still continues to be run by his long time partner Dr Linda Issacs. As for the links that come up when you google metabolic diet, they all appear to be gimmicks of some sort that may have a foundation in line with the Kelley protocol but that are selling you something whether it be supplements or a “program” of some sort. I would steer clear of them for that reason and stick with the only diet that has been shown scientifically to treat or cure any disease, a whole foods plant based diet.

      • PlantSlantMan

        Thank you. This is a pretty huge thing actually. There is a lot of confusion about metabolism and the metabolic typing. This is why I am interested.

        A significant part of the “alternative” world (naturopaths, holistic nutritrionist, etc.) advice patients referencing their metabolism or metabolic type. How many times haven’t we heard: “Oh I should eat protein for my metabolism” or “I have to start the day with protein to start my metabolism”.. Etc…

        This notion of “metabolic types” needing different dietary patterns (i.e. metabolic typing diet) is carried forward by the media and is living full blown in the public. I would love to see a Greger Debunk of Metabolic Typing Diet, as I think it is severely needed to put this straight.

        • payoung

          I couldn’t agree more!

          • PlantSlantMan

            Is there a way to get the Greger Teams attention to prioritize this? (even though they are already doing a wonderful, amazing job and have tons of great videos coming as well as in the pipeline already probably).