Does Your Blood Type Determine Your Optimal Diet?

BloodI get a lot of emails about the “Eat Right For Your Type” diet, also known as the blood type diet, which asserts that specific optimal diets exist for each blood type. In this post, I’ll take a look at whether there’s anything to this idea, and whether you should change the way you’re eating based on whether you’re Type O, A, B or AB.

The proposed diets all tend to be pretty decent, whole foods-based ways of eating, and they’re all better than the standard American diet of industrial processed junk, but differences do exist. Here’s the basic breakdown of all four blood type diets:

Type O (PDF): The “original” blood type and the oldest one, proponents claim it evolved among hunter-gatherers in response to their (Primal) diet of animals and plants. People with this blood type do best on meat, fish, and certain fruits and vegetables while limiting starches and omitting grains (especially wheat), beans, legumes, and dairy. It’s pretty much a strict paleo approach.

Type A (PDF): The agricultural blood type, proponents claim it arose after the advent of agriculture. People with this blood type do best on vegetables, fruits, grains, beans, legumes, and limited fish. They should avoid meat, wheat, and dairy. It’s basically a vegetarian diet.

Type B (PDF): The “nomad” type, proponents claim it arose amongst pastoralists raising animals for meat and milk. People with this blood type do best with lamb, mutton, rabbit, and most other meats (except for chicken and pork), dairy, beans, and vegetables. They should avoid wheat, olives, tomatoes, and corn.

Type AB (PDF): The “generalist” blood type. People with this blood type can eat many meats, some seafood, dairy, beans, grains, and fruit, but they should limit kidney beans, lima beans, seeds, corn, beef, chicken, and buckwheat.

I see a few things wrong with their reasoning:

First, they’ve got the anthropology all mixed up. Type O blood isn’t the oldest blood type, nor was it formed by human dietary patterns. The most recent research has found that Types A, B, and O arose almost 20 million years ago in a far-off ancestor common to humans and other primates – long before humans hunted, gathered, farmed, domesticated animals, or even existed. In fact, if anything, it’s type A blood that’s the oldest.

Second, if type A blood arose in response to agriculture, why would the Australian aboriginal diet of meat, marrow, and foraged plant foods, or the Sami diet of reindeer blood, meat, and milk and fatty fish both give rise to a preponderance of type A blood carriers? Type A is supposed to be founded on agriculture – grains, beans, with very little animal products. If a high-animal foods diet selects against type A blood, why does it flourish in these populations?

Third, the justification given for eliminating certain foods from these diets is that the lectins found in them trigger agglutination (clumping) of the red blood cells when consumed by someone with the wrong blood type. So, lectins found in olives are supposed to cause agglutination in Type As, lectins found in grains are supposed to cause agglutination in Type Os, and so on. Proponents claim that specific lectins are selective in their tendency to agglutinate – they interact differently with the various blood types. This supposed selective agglutination is the proximate arbiter of whether a food belongs in a particular blood type’s ideal diet or not, but it doesn’t even exist. The actual research suggests that lectin agglutination is non-selective with regard to blood type. If a particular lectin agglutinates, it generally agglutinates across all blood types. If a lectin is harmful to one blood type, it’s harmful to all.

That said, the blood type diet folks do highlight an interesting observation: the individual blood types are often associated with different rates of certain diseases.

Type Os have a curious relationship to certain infectious diseases. While those with type O blood are more resistant to contracting cholera infections, if they actually get infected, they’re more likely to have an extremely severe reaction. It protects you until you get cholera, after which it leaves you extremely vulnerable. The extreme virulence of cholera to this blood type may even explain the relative paucity of type Os in areas where cholera is common.

Type Os also are far more susceptible to ulcer, now known to be caused by infections from H. pylori bacteria. This is likely explained by the greater preponderance of “H. pylori receptors” in the guts of type O individuals.

Against other diseases, however, type O seems to be somewhat protective:

When compared to other blood types, type O is associated with lower rates of heart disease. The studies (comprising roughly 90,000 people) determined that 6.27% of the cardiovascular disease cases could be attributed to having a non-type O blood type.

Upon reviewing twelve separate studies, researchers determined that type O blood confers protection against pancreatic cancer. Type B was most strongly associated with pancreatic cancer, followed by types AB and A, respectively. Despite the results, “the mechanism by which these SNPs influence risk is unknown.” It could be that “these SNPs may act as markers of allelic variants in nearby genes, and the ABO antigens may not be directly involved in” the development of pancreatic cancer at all. Then, once a person has pancreatic cancer, type O confers a significant survival benefit over the other blood types. This may be explained by the observation in animal studies that the immune systems of types A and B seem to have a harder time at “noticing” and “destroying” cancer cells.

Type Os are also less likely to get gastric cancer, despite their increased susceptibility to H. pylori infections (usually a risk factor for gastric cancer).

These connections are worth looking into and deserve further study, certainly, but they have nothing to say about what diets work best with each blood type.

Obviously, I agree that certain kinds of dietary lectins are problematic, especially if they make it past the gut and into the blood stream. They’re a big reason why I avoid most grains, beans, and legumes – not only do they contain large numbers of lectins, but the lectins they have tend to be particularly proficient at disrupting and navigating the gut barrier. And yes, some people seem more sensitive to dietary lectins than others, but I see no evidence that a person’s lectin sensitivity – and thus ideal dietary composition – is determined by their blood type. It’s an attractive idea, the notion that we can determine someone’s optimal diet and offer them perfect health and protection from disease simply by checking their blood type. It’s just not a realistic one, according to the available evidence.

In the end – and this might be the most important part of this whole thing – the blood type diet “works” because it eliminates processed food regardless of blood type, removes wheat from the diets of people with blood types A, B, and O (which takes care of the vast majority of the population of the world), and recommends that most people (type O is the most common blood type) eat a diet based on meat and plants with little to no grains, beans, sugar,and legumes. I’m honestly not all surprised that so many people get great results.

What about you? Have you tried the blood type diet? Do you know anyone who’s tried it and had success – or failure? If so, what type were they?

Thanks for reading, folks!

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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340 thoughts on “Does Your Blood Type Determine Your Optimal Diet?”

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  1. Interesting article. I always found the blood type diet kind of asinine. It just intuitively doesn’t make sense to me. The fact that I’d have to be essentially a vegetarian on this diet doesn’t help its cause either. 🙂

        1. I’ve tried the blood type diet but I am a type A and being almost vegetarian simply does not work for me – primal is where it is at!

          1. My youngest daughter and current husband are type a positive and the thought of th type a diet being vegetarian for them is no go. I am type o negative the most universal blood there is as well as rare and yes I gave blood when I was able tooz but as for the diet im in luck I’m on the high protein diet occording to it, but as a type o period my oldest daughter and I get sick from certain meats such as pork and lamb and can’t explain why that is? My oldest daughter is o positive though not o negative like me. Any thoughts into why we get sick on only hose type of meats and no other’s?

          2. The Type O diet forbids pork. As for lamb, I don’t know but the diets recommend all meats be from animals raised on organic food, pastured, etc. Maybe that makes the difference.

    1. Thanks for the article Mark!!!!!!!! I read this book about 8 years ago and have since then tried to adhere to most of the reccommendations listed for type O and type AB. Cooking for two different blood types requires sifting through the allowed foods and coming up with a meal plan for both types. It is a challenge until you get used to it BUT then it is amazing how much better you feel.A friend of mine borrowed the book and got his whole family going on this approach and attained the same results. Like you said Mark,it basically cuts out all the crap and allows you to focus on what really matters.

      1. I tried ER4YT in 1999 but failed miserably because I rarely prepared food at home, a bad sign regardless!
        Fast forward to 2011, I decided to give it a serious effort. I was strict with following the recommendations for Blood Type O and even took it to the next level by having my secretor status tested; I am a non-secretor, which altered the food list slightly.

        I managed to feed myself and my daughter (A, non-secretor) following the food lists. My husband (AB, secretor) and son (B, secretor) were not as serious about following it but did subscribe to it loosely.

        Besides the fact that it was a HUGE challenge to organize food for our varied blood types, I did manage and now know that I can do ANYTHING if I set my mind to it. When people give me excuses for not being able to keep up with their personal responsibilities then I KNOW they haven’t pushed their limits. Try eating for your blood type for two years and then get back to me…

        With wonderful results: my joint pain reduced, but my daughters’ symptoms still persisted. I felt frustrated with the lack of medical support except for offers of medication so I opted to try the ALCAT test for both of us.

        So now, March 2013, I have taken it further and did the ALCAT test which is a blood test that tests individual food intolerance & sensitivities. I prefer this approach because it takes the guess work out and narrows the focus onto the individual, not the group.
        I also like it more because it is about reintroducing foods gradually so as not to be avoiding foods for life, unless there is a true allergy.
        Eating the same foods all the time, even if they are beneficial can cause a level of toxicity in the body.

        An interesting element that I had never heard of before is that for optimal absorption and to safe-guard against future problems, we should attempt to eat our food based on a four day rotational diet. Which means to not eat the same foods for four days.
        Now give that one a go!
        It can be hard enough not eating the same food two days in a row!
        Anyhow, I’m on a roll with this and though it requires a tremendous amount of planning and organizing, I am beginning to get a handle on it and LOVE it.
        My kids and I are eating more variety of foods than ever.

        check it out: alcat (dot) com
        I’ve started a new website called youasacook(dot)com which will record my experiment with eating this way.

        1. cool – looking forward to seeing how you make this all happen!

    2. I was told I should eat type A diet by my friend while visiting her. I’ve been following your food plan and she does too (she is type O). She was suggesting A plus Paleo. I cannot make myself go back to grains or beans of any kind and continue to just eat – Paleo or whatever it wants to be called. I tried the rice etc. but it is hard on my body. Thanks for the articles. h

    3. FYI-I’m a type o-non secretor and my sister is a type a-secretor, I’ve lost 30 pounds on this diet and feel great, something must be right about all this, since everytime i eat vegetable protein I feel nausea, but since my sister is type A, the vegetable protein seems to work for her, I actually get shakey if I don’t have meat protein by 3:00 in the afternoon, maybe it’s all in my head but I feel great on the diet, if I eat grains (other than rice) I feel lethargic. It can’t hurt to reevalute what you are putting into your body, my suggestion, keep an eating journal and document how you feel after certain foods are consumed.

    4. I have been doing this diet about 2 weeks now with A+ blood type. So far I have loved the results losing about 10 pounds. I was not overweight to start with but trying this for healthier living and to lose a few pounds. I signed up for a program which gave me recipes, a daily meal planner, etc which makes the program easy to follow. I generally get migraines and headaches a few times a week but so far, knock on wood, no headaches so something must be right between the diet and health benefits. I agree part of the diet works because I have eliminated sugars (sweets), breads, red meats (but I do eat turkey which is allowed), and dairy products but sometimes all you need is a health diet like this which keeps you on the correct path of eating healthy.

    5. Likewise. As a Type A(-) it’s recommended that I eat veg. Problem is, I really don’t enjoy veg, I enjoy all the food that is (supposedly) ‘bad’ for me: steak, duck, pork etc.

      Why live a life of misery eating food one hates?

      1. RE: being blood type A but loving type O foods. Any blood type has two alleles meaning that you inherent one gene from your mother and one from your father. So blood type A is a phenotype (observable characteristic) and not a genotype. The phenotype A is either the genotype AA or AO. So I don’t doubt that A’s can eat O foods if they have the later genotype.

        On the other hand, we are strongly conditioned not to eat our vegetables in our Standard American Diet (SAD). With everything we buy (but fresh produce) being laden with sugar and salt. The more you eat your living-enzyme-rich vegetables, the more your body will crave them. Dead vegetables are no more good for you than a doughnut.

        1. Help me! Geri!… I am supposed to be blood type A+… I have no problems with corn and beans and fresh steamed vegies… love them. Avo, salsa, etc.. but I too crave beef! I love fruit and cow’s milk yogurt and almonds!

          Using your info, would in help me to inquire as to my father’s and mother’s blood types so that I may understand this phenotype/genotype relationship?

          Thank you!

        2. Chris,

          Corn (and soy) in general is isn’t good for anyone. It’s an endocrine disruptor and will make you fat. That’s why it’s fed to livestock. Dr. D’Adamo links corn (according to the fossil record) to bad bones and teeth as previous to its mass ingestion, humans had good teeth and bones. Btw vitamin K2 is needed for strong bones and teeth and only found in animal products (humans have lost the ability to convert K1 to K2 although our gut bacteria produce it in small amounts) so perhaps that’s why you crave meat. Unfortunately, grain fed livestock of all kinds are deficient in K2 and in turn so are we.

          As for your blood type genotype: your parents’ blood types may help you narrow it down or if you have children and know their blood types. Google how to use Punnett Squares to see the likely hood of inheriting certain genes. O is a recessive trait, and both A and B are dominant.

          So, if both your parents have A type blood then you won’t know for sure what your genotype is, since either one can have either AO or AA gene combinations. But if one of your parents has type O (OO) then you know for sure you are AO since the O type parent can only have donated an O gene.

        3. As type A I should not eat beef, but a Dr. Told me elk, bison, and venison were fine. That is of course no more than 4oz at a time.

      2. So long as you feel great, why fix it, if it isnt broken. But for people who begin to suffer, pain Arthritis. Migranes, so fourth & so on. Trust Me…. Its worth it…

  2. According to this, my type B can do dairy. According to my body, I cannot. Nope, no blood type diet for me.

    1. And what will they come up with next, a diet based on body shape? Oops, they already tried that one too!

    2. I saw the same thing and had the same reaction… I don’t mean to be pessimistic, but it sounds like they had a team of astrologists on the job deciding what foods to put in what categories.

      1. Then they are correct. Because a astrology chart based on you done with your exact time and place of birth will give you a very accurate description of your personality traits. Which can go whatever way your mind frame is in.

      2. I’m sorry but have you read the books? The diet is based on clinical observation and further research based on those clinical observations and not astrology. Until personal genome testing becomes affordable, Dr. D’Adamo’s blood type and genotype diet plans are as close as you’re going to get to inexpensively understand how lectins (proteins) in our food react with our blood chemistry.

    3. Kelly, if you had read Dr. Peter D’Adamo’s book “Eat Right 4 Your Type”, you would know that you can have allergies to certain foods in the categories normally okay for your blood type. He also points out the more compromised one’s immune system is, and the more health issues one has, the more sensitive one’s system becomes, thereby narrowing down food choices. His dietary recommendations are the best scenario. It is not all-inclusive.

      1. Dr. Peter D’Adamo states that the blood types are determined by your gut microbiota (enterotypes). And it makes sense.

        I am not quite sure if the corresponding dietary recommendations — as stated in the article — are valid too. It is probably a more complex issue (gut flora signalling — nutrition for the host — gut flora shifts via dietary change etc.) But people like their commandments.

    4. Have you tried raw dairy? There’s a huge difference between that and pasteurized/homogenized.

    5. The food and beverage lists are guidelines and not absolutes. B’s typically can handle dairy because B blood type is represented by D-Galactose and milk is represented by Galactose. Normally your body would not see this as an invader and give you problems. You might not be Galactose intolerant, just lactose intolerant. This can be associated with being a Non- Secretor.

      The Blood Type Diet is all about individuality. Just because a food is on the beneficial or neutral list does not mean it is beneficial or neutral for you.

      B’s do best when they avoid chicken, corn and wheat. If you notice any other problems foods eliminate them and you’ll do just fine.

    1. Study the science behind the diet before coming to such uninformed conclusions.

    2. The very lectins that Dr. D’Adamo has found to cause problems with each blood type are the same food lectins used by scientists and doctors used in antigen staining for cancers and pathogens.

      Staining is the same as binding and scientists and doctors have been using food lectins to identify specific antigens in cancers and pathogens for over 50 years.

      1. Lectins were mentioned in the article above. It appears that in research done by other people shows that if a lectin causes a problem with one blood type it is almost always a problem for all blood types. In the article above, there is a link, which lists 107 food items, give or take. I only counted once, so there is a slight margin for error. Out of those 107 foods, only 2 caused agglutenation for some blood types and not others. Another 3 caused differing amounts of agglutention for differnt blood types, but caused aagglutentation for all. And those lists don’t match. For example, in the link in this article, Lima Beans caused agglutenation for blood types B and AB, but on the blood type PDF’s linked to in this article, Lima Beans were “Most compatible with your type” for type B and “Always avoid” for tupe AB. And while Lima Beans caused no agglutenation for types A and O on the blood type PDF, for type A they’re “Always avoid” and for type O they’re “Use moderately.”

  3. Once I ate the wrong kind of food for my blood type and I turned into a newt.

    1. “A newt?!”

      “Well….I got better…”

      Sorry…Monty Python and the Holy Grail reference…

    2. +1 ! I got better!! 🙂

      My SIL is / was a fan of ER4YT, but I couldn’t understand why my brother (type O) “evolved differently” from me, his sister (type AB).


  4. My family and I (4 kids and hubby) have been following the blood type diet for 2 years and counting. Most of us have had enormous sucess with it. My 3 asthmatic children are off most of their meds and only occasionally does 1 need his rescue inhaler. My fertility issues have resolved resulting in a 4th child! Also my pre-hypertensive blod pressure is normal and unexplained tiredness is gone. and no gestational diabetes during my last pregnancy. no recurrent sinue infections. i could go on and on. I am type O and find that the primal lifestyle is very close to what i am eating. My husband (type A) is not “on board” with the blood type diet so i have him on a primal diet. I figure getting rid of the grains can’t hurt!

    1. This struck me as funny. Your husband is NOT following the “ideal diet” prescribed for him as a type A – and so both of you are following the paleo lifestyle. Doesn’t this mean that the paleo lifestyle is what’s working…. and not the blood type diet?

    2. What blood types are your children? According to the Red Cross’ web site, with a type O and a type A parent, the possibilities are A or O for each child, so you’ve probably got both mixed in there. Do you have each child on a blood type specific diet? I truely am curious (see my user name). Sounds like it would be a bit of a pain, as one should eat plenty of meat, while the other should avoid it, one can eat grains (except wheat) legumes and beans (aren’t they legumes??) but the other can’t.

      1. Actually they are not equal, you can have type A blood with an AA gene or AO gene, the O gene is always recessive. So if Dad is AA, all the kids will be AO which is type A, but if Dad is AO there will be a 50-50 chance of both.

        1. I figured there was a little more to it than that, since type O is the absence of the markers for types A and B. Since to have a blood type of A, one would have to have the markers for type A, my first thought was that a type A parent could not produce a type O child, but double checked the Red Cross’ site first to be sure. I briefly considered digging a little deeper to find out how an A or B parent could produce an O child, but decided against it.. Leave it to another Bridget (I’m Bridgette) to look into it. 🙂

        2. Bridget, you are correct. A friend is a B blood, her husband is A. They have six children, A, B, AB and O; therefor her husband must be an AO, and she a BO for such a clan. She adheres to the D’Adamo plans and is amazed how preferences of each blood type has individual preferences that mirror their blood types.

          It is possible for even the A blood diet to do a paleo diet using chicken, fish and eggs according to the beneficial and neutral lists.

    3. Excellent results! But you said it best when you said the primal lifestlye is very close to what you are eating. My guess is you’re 80/20 primal, which is why you’ve had such great success more so than because your blood type is O.

  5. Finally an article about blood type and diet that makes some sense to me. I looked into the blood type diet many years ago and being a type A tried to follow the whole vegetarian thing…with disastrous results. I come by insulin resistance honestly as a familial thing (not sure if it is genetic or dietary) but we all have thick middles on both sides of my family. So I now know that a diet rich in grains and other carbohydrates is about the worst thing I can eat.

    So I’ve ignored the whole thing as complete nonsense, even before I was introduced to Paleo lifestyle. I’ve thought about it some lately as it still comes up and I’ve now learned that I actually thrive on a higher intake of meat and fat than many people. Honestly I think my body would be thrilled if I fed it nothing but fatty meat and piles of green vegetables (but as a foodie I would not find that emotionally satisfying.) IF the blood type diet has any credence at all then it would make sense that Type A is actually the oldest and my carnivorous body has an excuse. But I don’t need any excuse to eat what digests the most easily and gives me the best energy and calm demeanor.

    1. My story – exactly. So mad at myself for buying into that hype years ago. I feel incredibly good eating fatty meat, veggies, and a seasonal fruit (pervasive where I live).

      1. Oh ditto ditto ditto. I spent 20 years eating the “ideal diet” for my type A blood. Vegetarian, whole grains and legumes up the yin yang. What did it get me? Chronic inflammation, severe heartburn at age 30 that I was told would require lifelong prescriptions to control it, constant fatigue, migraines, a good 20 extra lbs and oh, terrible anxiety. Then I ate a piece of fish. HELLO. All the receptors in my brain went off like fireworks. Then I ate a piece of chicken. OMG, same reaction. Then I ate a big local grassfed steak. It was like CRACK. Fast forward 2 years: I NEED to eat meat (and lots of fat). My body knows it. I don’t need to eat lots of carbs. I really really wish the media would stop spreading crappy advice around to all the poor type As and Bs and ABs out there.

        1. Ditto, type A here, was veggie, very high carbs – not good AT ALL (2 diabetic pregnancies, bipolar … )!

          Well now on Primal, high meat/fish protein, enjoying fat.

        2. Robyn, it sound like you listen to your body. I am an O blood and follow Dr D’Adamo’s diet strictly. Legumes and grains and acidic fruits and any carbs do me in. I tried the Ornish diet four months, gained forty pounds, and my blood tests for cholesterol and triglycerides went into the danger zones. Processing of our foods has gone to the extreme, as well. Wheat, for example, now seems to have 48? chromosomes where original wheats had 23. (I may be off a number or so.) This kind of modification may be one reason so many people have trouble with this and other grains and other plant foods.

          I’d be curious how an A blood Paleo diet based upon D’Adamo’s plan using chicken, fish and possibly eggs might work when grains, legumes and other high starch foods are abandoned. I know Mr Taubes (Good Calories, Bad Calories) eats a high fat, moderate/high? protein, low carb diet. He is of A blood type. He is younger, leaner and better exercises than I, yet I have superior blood specs. My five younger siblings eat a fairly good diet based upon the food pyramid, avoid animal fats, use vegetable oils. Two do partake of fast foods and one has diabetes. The other three mostly avoid over-processed foods. These three have fairly good blood specs, but mine are far superior: cholesterol 4.3, ultra low, low density; triglycerides 0.9 mmol/L. I feel that if we can learn to listen to our bodies we do best. There is no easy, single answer for all.

  6. I am a Type O. However, years ago, before being health conscious, I dismissed this type of diet. Don’t know why, just a “gut” feeling. (Pun intended!). Glad to see a real honest review. Great post. Thanks!

  7. I’m type A and have looked at this several times in the past. I keep giving up with it because it recommends a mostly plant-based diet. I *have* noticed though that the foods I have the most problems with are on the “no” list for my type but overall I haven’t found it to be terribly helpful and like the above commenter have dismissed it in favor of paleo/Primal and self-observation.

    1. I’m A neg and I’ve also looked into the blood type diet a few times too.
      In some way it led me towards paleo/primal because it made me think about my ancestors and where I evolved from.
      Although being a Northern European type, limited fish seems a bit odd.

  8. Yes, being a Type O I have been following the diet, but I have been calling it the paleo or primal diet all this time. It works pretty well. I feel healthy, happy and strong.

  9. Yup, in my experience it seems to be the Os who benefit the most and the As are either not liking the vegetarianism of it or not doing all that much better. Everyone benefits from going gluten free, it’s a good first step into Paleo. (I’m an acupuncturist and do “gentle” diet recs )

    1. I find it interesting that I am type O AND I am Coeliac. So I definitely benefited from a gluten free diet!
      Its a shame that people think ‘gluten free’ alternatives like GF pasta are better for you. They are if you are coeliac, but their is virtually no nutritional value whatsoever.
      It naturally became my first step to the Paleo diet, as going gluten free for me was about finding foods that are naturally gluten free, and avoiding GF foods that imitate a gluten containing product…. like bread

      1. Type A+ and Coeliac – so completely wrong for me.

        Interesting factoid: Type O is most common in UK as a whole but type A is most common in North East England – the area most impacted by the Vikings!
        Type A is also most common in the Scandinavian countries ISTR.

        1. @ Liz: Coeliacs should also avoid barley and rye as they can (and in my case do) trigger the immune response.
          I also don’t do very well with oats or corn for that matter so the grains is right out – other than rice.

  10. My wife and I checked out one of those books from the library and tried to figure out what type we were with the physiological ratios. We measured our leg lengths and head shapes and all that. At the end of it all, we were underwhelmed. Neither of us fit squarely into a particular “type” and when we looked at the list of foods to eat and foods to avoid, it seemed overwhelmingly specific.

    My takeaway is that it seems likely that there are differences between people and how a diet will affect one person is different than how it will affect another person. It would be great if we could somehow determine scientifically what the best diet for a given physiology would be. However, it seemed unlikley to me that blood type is the best indicator.

  11. And how about the few of us that have the rare blood type AB neg

  12. The blood type thing sounds a bit silly, although I would imagine eating a paleo diet modified to better suit your genetic heritage is probably beneficial. As in someone from an Irish descent may do a bit better with some extra potatoes thrown in than others.

    1. And us Scots can have some extra beer thrown in our diet right? 🙂

      1. Perhaps, depending on the quality and type traditionally drank, and the dietary and lifestyle context its consumption occurs in.

    2. Problem with that is, potatoes are not an “ancestral” food for the Irish. Potatoes were introduced from South America to Europe in the mid-1500s, not really all that long ago.

      1. Ah, you are correct. I probably should have Googled it first. Nevertheless, I think that the general idea is still fairly plausible.

    3. Actually, potatoes weren’t in the Irish diet until they were brought back from South America and made their way to Ireland.

    4. Oh please no more potatoes am of Irish parents and bought up exclusively on them

    5. I like the “genetic heritage” angle in principle. It makes sense to me. One problem is how far do you go back looking for dietary differences? How did an Asian diet of 20Kyears ago differ from a European one? Maybe some day we’ll have answers to those kinds of questions. In the mean time I’ve been hearing pro-grain people trying to convince us that paleolithic people ate grains, which makes me suspicious of ANY scientific results regarding ancient diets.

    6. My family heritage is largely Irish and, curiously, both my mother and myself are allergic to nightshades, which include potatoes. Odd, eh? My blood type is O, though I never looked into the blood type diet.

    7. Potatoes weren’t native to Ireland only a few hundred years ago, so probably not. 🙂 They were introduced in the 1500s to Europe, not long enough, likely, to significantly adapt to a primarily potato-based diet. But in general, I agree with your premise. Those in ancestrally fishing societies probably do well on more fish and those with a lot of dairy in their ancestral diet probably could handle more dairy. Eskimos do well on an almost exclusively meat diet, while most of us would probably not do fabulously without any veggies at all.

  13. I tried the blood type diet when it first came out, 10 or 15 years ago. I’m A+, so it had me eating little to no meat and lots of grains. I gained weight, esp. around my belly, and felt like crap.

    One thing that really turned me off the “evidence” of blood type diet was when I learned that chimpanzees ALSO have ABO blood typing. That pretty much refutes any argument they might make about Type A arising from the advent of agriculture!

    1. I also tried it when it first came out. But I’m an O, so it was a paleo/primal-style diet for me. But that’s all it was. A diet. So, I missed simple carbs too much, gave it up, and that was all she wrote. But I’ve been eating primal for about 2 years now. This isn’t a diet. It’s a lifestyle. And, for the first time in 19 years, I don’t have acne, migraines, constant back pain from scoliosis and post-traumatic fibromyalgia, depression, severe anxiety, fever blisters, daily headaches, almost constant nausea, or trouble sleeping. Plus, I’m producing some seriously nutritious breastmilk.

  14. Dogs (and probably many other animals) have different blood types. Does that mean they need to eat a type-specific diet also? Seems a little absurd.

  15. I once had this book, and decided to do an N = 1 experiment on me & Hubby. Hubby’s a Type A, and his gout suggests he’d do well going vegetarian, so he did…right up until he kept getting meat cravings that would not be satisfied with extra B-12, iron, or TVP. (this was all before we’d even HEARD of Paleo or Primal)

    Since I’m a Type O, I tried eating his extensive lists of legumes, grains, etc., and that’s how I developed allergic reactions to them–most of them were alien to me (Adzuki beans, for example). I even employed the WAPF method of soaking grains and beans overnight in an acid solution…to no avail. I was still having reactions.

    I even went so far as to make a list of foods both blood types had in common, and focusing on them–HA! There were so few foods, it wasn’t worth the bother.

    It was far easier to just eliminate these foods from our diet than it was to jockey around with different types for different people. The Paleo and Primal diets also have offenders in them for us, but the common denominator is MEAT–meat that isn’t broken down by species or blood type. And according to several people who seem to have done their homework, you can get pretty much all the nutrients you need from organ meats and bone broth, so who needs the other foods?

    What do you do when this diet recommends a Type A eat meats he can’t stand, or meat he’s allergic to (like fish), or a Type O is allergic to half the foods on the “must eat” list? You ditch the book and look for something else, and that’s exactly what I did.

    1. I dealt with this, too! My husband is type A and refuses to follow a vegetarian diet. Since he also has collitis, that’s probably a good thing, since the vegetarian diet involves A LOT of soy products.

      I, on the other hand, am type O. And the idea of eating meat was a-okay in my book. What drove me nuts was that some of the things I really love but don’t eat often (cashews, anyone?) were not “allowed” in my blood type’s diet.

      So glad to see this post. The primal lifestyle is working so much better for me than the blood type diet idea ever did. Now, I think I’m gonna go find me some cashews. 🙂

    2. As my uncle the crazy Pharmacist would tell you, gout is less a condition involved with meats and more about sugars and grains. He gave up both those but continued to eat red meats(oh no) and his gout went away.

  16. My husband & I followed Eat Right 4 Your Type in 1998, then changed to Live Right 4 Your Type diet & exercise recommenations when that book came out – we have benefited so much.
    We saw a big difference in the way we felt when we changed our exercise methods based on our blood type & when we eat foods off the avoid list we do have a negative reaction.
    Sometimes the negative reaction is immediate after only one time eating the food & sometimes it only happens when the avoid food is eaten frequently over a short time.
    My blood type is B & my husband’s O. I’m more sensitive to my avoid foods than he is to his.
    There are very few avoid foods that we don’t have a reaction to. It might be because we have been sticking to the diet since the late ’90’s

  17. I am an 0+ and so are many in my family. All of us have found that we perform and feel better on a diet consisting of meat (at every meal), nuts, veggies, and little fruit. Beans do not seem to be problematic… at least in terms of blood sugar. We all are susceptible to sugar, alcohol, and grain induced migraines.

  18. My Grandmother follows this diet religiously and its done wonderful things for her! She is Type O so I agree with the article’s conclusion – the strong benefits of Paleo are most likely the reason she’s seen success. Since it works so well for her, and she believes in it so much, there’s definitely a benefit to the diet for her! Through her journey I had a friend with Type A take up that diet and its been amazing for him! Going Vegan has been the best thing he’s ever done. Not sure I buy into the science, and these two cases could just be coincidence that their Type diet fit with their physiology, but there’s definitely room to research!

  19. I have done well on the next generation of this diet and you have part of it wrong. The next generation or Geno type diet has some A’s eating meat because they need it. I am one of those types. If you checked into the software D’Adamo created you would know that you can put in all health info and other physical info and get a specific diet created for you. Explorers and Teachers can be blood type A and have to eat meat protein.

    This diet is more about avoiding certain foods that cause inflammation in the body. Please get your facts straight.

    1. Explorers and Teachers? That sounds like even worse pseudo-science than the blood type thing, again drawing from the example of Japanese culture and the association of blood type with personality.

      I think Mark was too kind to this diet. If it’s really this goofy, and exploiting people by playing to superstitious beliefs about personality types, then it deserves another article.

      1. I agree, Dave. Mark has to walk a fine line and not put people down. But come on! Explorers and Teachers? Does the software have a Slacker option? Stupid.

        1. Nope, no slackers, which FORCED me to choose paleo. Man, the worst thing you can do to a slacker is force them by offering no other alternative. 😉

        2. The category names are simply nicknames meant to satisfy people who can’t easily deal with the complexity of the new theory w/out simple titles.

          If you can and would like to, the statistical observations/analysis that define each group are on the genotype diet website. A background in genetics would help, but isn’t necessarily required.

    2. Yes, the updated Genotype theory takes additional factors into acct – the creator of the A, B, AB, O theory calls this more basic info outdated.

      One problem is, the average person wants quick, easily categorizable info, which blood type theory provides. The genotype diet is quite nuanced. It takes thought and some time consuming analysis to determine what group you’re said to fall into. For example, type A-‘s, O-‘s and B-‘s are more likely to fall into a higher meat eating group than A+’s, but many other physical attributes (incisor shape, skull shape, limb bone lengths) are also key determiners.

      In short, the new categories (teacher, explorer, hunter, etc) cross blood type lines, but blood type is a heavily weighted factor.

    3. Kim, you sound like you a) listen to your body signals, b) willingly think out side the box, c) understand that rare is the rule that applies to everyone. You will do well with such an arsenal.

  20. My Dad was suffering from gout as well as excess weight, even though he ate a lot of fruits and veg, not that many grains, and goes to the gym regularly. I read up on the blood type stuff and did some research through my university library access. I found that much of what the blood type diet book was correct. The most important thing I found was that inflammatory responses are different according to blood type, so I then understood why he, as a Type A, was getting gout. So, I gave him a list of foods to try to stick to, but allowed him to deviate a little bit because he loves meat. His gout was gone within a week and he immediately started to lose weight. He lost over 28lbs and is now stuck at a good weight for his size. He says he feel great. He has also stopped getting digestive problems which he had on and off ever since he had cancer treatment about ten years ago.

    1. This is so true for me as well. I’ve had spirts of gout and am Type A. After some crazy research I adjusted my diet from 70% meat to 20% meat. Sorry I just love meat. However, increased my veggie intake to 70%, eat crazy amounts of Cherries and Stawberrys (a good source of anthocyanins to reduce risk of gout). I now have not had gout returned, lost 18 pounds and feel great 🙂

  21. About a decade ago a coworker tried to talk me into the Blood Type Diet. I did some research and I found a critical review that said it was no more scientific than a Bellybutton Type Diet. Are you an Innie or an Outie?

    1. I’m an In-A-Gadda-Da-Vida, baby…don’t you know that’s it true!

  22. Japanese culture has a lot of pseudo-science about blood types, so I was immediately skeptical that the blood type diet wasn’t more of the same. The cynic in me even wonders if it wasn’t inspired by it: Japan provides the example that some people are gullible for blood type pseudo-science, and a “lightbulb” goes off suggesting that Westerners might fall for the same thing if it’s turned into a “diet”.

  23. I tried the blood type diet back when the book came out. I’m type O so I did well on it. I don’t remember why I came away from it. I’ve been primal for three years and loving it.
    The most I interesting thing in this article is type O and H Pylori. I recently was treated for this and I am feeling so much better after a lifetime of digestive issues. Getting rid of grains, legumes & h pylori has made my life much more enjoyable!

  24. I was a vegetarian for ten years, eventually suffering from bad blood suger swings. About 15 years ago a naturopath told me to eat for my blood type — and it changed my life. I am “O”, so that meant eating meat. I thrived when I introduced meat, and likely simultaneously reduced grains. Now that I eat primally, I can see why it made such a difference. Mark’s explanation makes sense and alters my understanding of that dietary turning point that felt so drastic — and which I then attributed to be due to my blood type, when it was most likely a result of moving closer to primal and away from what can often be a “pastatarian” diet more than a vegetarian diet. I can now revise my blood type story about the day I stopped being a vegetarian.

  25. I’m A blood type and have followed the BTD and I’m a believer in it. Beef is an avoid for me and if I have it then it binds me up and I pay for it. Years of digestive health issues ended when I cut the “avoid” list of foods out of my diet. The occasional consumption of those foods and their effects convinces me that there is some truth behind the diet. I also combine the BTD with the Genotype Diet and SWAMI software which expands the food lists. I don’t think it’s a diet that can be strictly followed without consideration of other diet principles, such as those found in the Maker’s Diet and the Body Ecology diet. Healthy eating is really not very restrictive. When you experience the health differences of consuming one food versus another then it’s easy to abandon old eating habits. Interestingly, the BTD lists pork as avoid for all types, just as the Maker’s Diet does. Under the BTD, the avoids are the same as consuming poison. Beneficial foods are like medicine, right in line with Hippocrates’ philosophy, “Let food be thy medicine and medicine be thy food”. I never want to be so spoiled again that I eat whatever tastes good; it just does not make for a healthy life. I’m always a giver of platelets and recently a kidney donor, so, I have got great blood! I attribute my good health largely in part to the BTD.

    1. Collette, can u explain more about swami? An ND does it near me and I’m curious about it. I had my genes tested thru 23andme and wonder how this program might help…. Or is it a gimmick? I would love more details about it

      1. It’s money out of pocket to test your secretor status under the BTD and more money for the kit to figure out your Genotype. If you’ve already done those things then plugging the data into the SWAMI software (an additional expense to buy) just considers both diets together to give you a lengthy report with food lists. The SWAMI software also asks other questions about your personal and family medical history to further categorize foods that are beneficial or to be avoided, for instance, if you have high cholesterol, or joint problems, etc. I accomplished a food list without the software by comparing the two diets, but the software came out with foods that I otherwise would have not considered. For example, cheddar cheese is an avoid, but SWAMI showed me that colby cheese, which is actually a very mild cheddar, was a neutral food and ok to have in my diet. (I’m A type nonsecretor & Teacher genotype.) So… I don’t think it’s a gimmick, but Dr. D’Adamo must be making a lot of money off all this stuff! If you incorporate the BTD at its basic level and find it beneficial (I did) then I think it’s worth it to venture into incorporating other aspects. After following the guidelines of the BTD for a few years and correcting digestive health issues, I was still bothered by blemished skin which was aggravating as a woman in her 30s so I wanted to fine tune my food lists. I’m 40 now. Some of the trigger foods for my acne happen to be avoids under SWAMI. When I don’t eat healthy and according to my SWAMI then it shows in how I feel AND how I look. I’m convinced that there’s truth behind the program and I’m a curious individual who has bought lots of books and tried all the diets just to see what works. So, as I mentioned already, there are still other health protocols to consider besides what D’Adamo sells when adapting a personalized eating plan.

  26. My wife was diagnosed with Lupus over 20 years ago. Her immune system is overly sensitive. She eats a very strict diet with no processed foods. She is a type A, non secretor. We noticed very quickly that when she stays away from the foods listed as “Avoid”, her immune system remains normal. However, eating any variety of oranges results in strange inflammation of joints. Other Avoid foods produce equally strange symptoms. I have noticed that many of the foods listed as avoid for type O do not “agree” with me (pork for example) and I do my best not to eat them no matter how “natural” or paleo they may seem to be. I definitely notice a difference. I think there is more to the recommendations than meets the eye even though much of it seems counter-intuitive. I find many people have found by experience that they tend to already avoid many foods on the Avoid list for their blood type. Anyone eating paleo who still has lingering health issues should definitely experiment with the blood type guidelines.

  27. Would like to hear your take on the importance of “secretor status” and “genotype” in determining the diet. The EF4YT folks have moved on and now say that secretor status and genotype are more important than blood type in determining appropriate diet.

  28. Thanks as always for your articles and opinions.

    I think it’s a pile BS.

    I was 231 LBS. In 2.5 years I’m now 181 and counting. I eat mostly Primal BUT 2 days a week I let loose. Not crazy but I eat what I want and add non-Primal. 5 days a week, I restrict my calories to 1700 a day and Intermittent Fast for 18-19 hours.

    All my health markers are excellent!

    I’m B+ blood type and read the pdf. – Bull—t. I eat so many things they say not to and zero happens. Also the nonsense at the top of the chart along the lines of “if you experience any of these …” is a sham. They could put in, ‘If you scratch your butt then you may be prone to disease.

    Another BS hype that someone is making $ on.

    1. My thoughts too. When I first heard of the blood type diet, I immediately thought this was a gimmick diet. I still feel the same way. I did enjoy the way you worded it though! ; )

    2. Glad to hear it from you man. I am B+ too, and have been suffering from many health issues my whole life (low energy, insomnia, digestive etc.) and it ACTUALLY helps when I start to follow BTD. I think when you don’t have any health issues like me you can probably eat whatever you want. Btw you are B+, so quitting grains and legumes probably help a bit (so as meat eating). I chose to follow this diet because I know I have a (intuitive) liking for dairy, lamb, beef and wild meat in general haha

  29. Hi Folks:

    I started the non-secretor O blood type diet before Paleo. I’m 33 and lived most of my life in a fog being raised in a dysfunctional alcoholic family… so some of this is surely psycho/emotional… and when I started the O diet… following it with discipline… I had a 3 day stretch where I was so grounded, confident and solid I was blown away! It was as if I was the guy I always wanted to be and know I am deep down. Given I live in more anxiety, mania and depression, and have most of my entire life, that was proof in the pudding for me there is something to the blood type diet and paleo based approach. I recently adopted Paleo because I knew it was compatible with the O diet I use foundationally..

    After living in a fog for over 30 years of my life that says a lot.This is my experience and would love to hear about how this is for other O’s who have also integrated the blood type diet with Paleo!

    1. For people with severe physical health or mental health issues.. combining the paleo with the blood type diet is ideal…

      When you swallow the food… your gut bacteria instantly reacts with what you’re consuming… and if it is against type… inflammation occurs as well as as a somewhat addictive adrenaline response…

      I’ve come to agree that grains are almost universally not good for people… so following the paleo diet Mark talks about is great…. but then refine the foods according to blood type for further improvements…

      It takes people to radically lose their health to be open minded enough and willing to take these approaches. (as many blood type advocates have had to have a health crisis to be willing to try it consistently)

      Some people may complain about losing energy when improving their diet..(giving up grains, eating less often..etc). but its called giving their endocrine system a rest.. after all.. it sure is better than cancer, heart disease and autoimmune diseases which are created within our body to force us to STOP.

      1. Hi Steve:

        I liked what you just wrote. It makes sense to me having a pretty severe version of my challenges.

        I was a vegan for 13 years… 3 years of that raw/vegan… and while it worked in the beginning I got caught in an eating disorder like cycle of cleaning. That is where the psycho/emotional comes in. This seems to drive the addictions and doing things that aren’t healthy/don’t work.

        The diet helps and it can also be turned into a way of punishing oneself even with the purest of food like Mark writes about in his book. These issues in my experience started moving for me when I began exploring psycho/emotional rooted causes for why I was overeating and not eating well in the first place.

        Some of it surely is blood type and diet related, but they seem to play off each other in my experience. Like sticking with my best diet for me helps me avoid emotional pitfalls and confronting feelings and owning them also cuts out the suppression of truth that leads to wanting to numb out by overeating fruit, grains, alcohol or many forms of sugar.


    2. I’m O, and brought up with a similar family type, Brian S.. I found WAPF then primal but would never go back to even WAPF grain-soaking much less SAD, so densely thick, SO bad was the brain-fog/anxiety etc. with any grains at all.
      I had an acquaintance a while back at a playgroup who raved about my baking and hinted broadly my guest dinners would be amazing- turns out she was on the O-type BTD and raved about what it’d done for her entire system. I was encouraging when she said wheat and grains were history, but her husband- a different blood type- apparently chowed down breads at every turn. He didn’t look half so well as she.
      I mentioned this to my partner after we bumped in to them at the local farmers market months and months ago now, and he came up with a typically cynical (conspiracy-style) view to do with the BTD; perhaps they (“They”) are encouraging a certain type of blood type, a sort of opportunistic genocide… Think what you will. It seemed a curious and interesting thought to entertain at the time.
      I believe the primal principles are the very best way to go though, regardless of their differing names or how or where found.

    3. Brian,
      I’m a Type O/Paleo and I don’t have a success story to share, but am wondering whether to incorporate BTD with Paleo and your story seems similar to mine (living most of my life in a fog, dysfunctional alcoholic family…) and so I have a few questions, if you wouldn’t mind.

      What’s a non-secretor and how did you find out you are one? Do you avoid coconut, avocado, etc., as BTD recommends?

      Though I eat mostly Paleo I don’t feel as amazing as most people who eat that way seem to. I read the original BTD book but have not implemented its suggestions mostly because I’m weary of dietary experimentation – I’ve spent years adjusting my diet (eating this, not that) with only moderate success. I’m mostly looking for emotional/mental relief – I’m happy with my weight. I know we each have our own journeys but I’d be interested to hear how “strict” you are with the BTD – especially as it applies to the Avoids. Thanks!

      1. Karen, as an O type I find avocado helps with depression, quite dramatically so, so I’m just throwing that in fwiw. Most previous generations in my family going back to the late 1800’s were alcoholics, functioning but always dying of the direct complications caused by it. I suspect among other things an omega oil imbalance of some kind which is apparently common in northern European people, along with parental modelling that evenings = drink and all the usual stuff.

      2. Hi Karen:

        I recommend the Live Right for Your Type book by Peter D’Adamo. This combines his first book Eat Right for Your Type better and cover secretor status. You can order the testing kit through peter D’Adamo’s website. It is a one time test and will let you know whether you are a secretor or not.

        Basically there are people who secrete and don’t secrete their blood type antigens into their fluids. Those who don’t tend to have weakened immunity and more troubles not secretrting means your immune system isn’t take care of this stuff as efficiently as someone who does secrete their antigens into their blood.

        For me avocados and coconut (oil only) are beneficial being an O non-secretor.

        I also don’t get as much traction as I would like with diet and sticking with it helps. In my experience it is the emotional congestion at root. If you’re like me you may need get the rage out and get psycho/emotional support. Depression is rage turned inward on oneself where a boundary that needed to be set wasn’t. Otherwise diet just becomes another way we try to “fix” ourselves and make perfect. Don’t get my wrong it is part of it, but when people try so much with diet like I have with minimal traction it points to psycho/emotional. And if you were raised in the nightmare of alcoholism you may not be able to just bio-chem or diet away the needs and feelings.

        Hope that makes sense and let me know if you have any other questions Karen? Thanks for reachin’ out!


        1. Thanks for your very thoughtful answer, Brian, I appreciate it! I have done lots of inner work but you’re right – I do sometimes think of all this as “fixing” myself so it’s good to be aware of that. And it makes sense that no matter how “clean” I eat, mindset has a lot to do with how I feel physically. So, onward and upward, I’ll just continue to do my best and stop trying to fix myself! Thanks again.

        2. Karen,
          You are welcome and I just had my naturopath doc who introduced me to Paleo tell me how critical it is that I get psycho/emotional help to heal and recover from the abandonment I endured growing up.

          I wish that a perfect diet would just magically turn me into “the man”, but my experience is that feeling like “the man”… grounded, solid, passionate and confudent has come more out or emotional growth and expressing buried rage from having my boundaries violated has made me feel better than any diet.

          I’ll continue to eat best based on my O type and paleo cuz it clicks… but the psycho/emotive growth is the way to reclaim myself in the ways I wish for to serve my dreams of heart!

          Cheers and best to you Karen!

  30. I’d say that since most of the blood types specifically state to not eat wheat, that any benefit they derive is probably from eliminating that from their diet. The rest is horse doo doo. It was once suggested at a chiropractor’s office that I should start this diet. I looked at the list of foods I wasn’t suppose to eat (which included a lot of my favorite fruits and veggies) and said ‘no thanks’.

  31. I´m a type A and just the “no meat, limited fish” made me go heeeeeeell no!
    I love fish and seafood. I did have a problem with sigesting beef but it went away, like magic, along other disgestive issuses once I excluded all grains from my diet. 🙂

    1. you should look at the genotype diet. I am A, and follow the warrior guidelines and eat alot of fish, shellfish and turkey.

  32. I noticed some time back, that my patients who were type O did better than the other types at dropping weight and improving energy. So I decided to try it, me being a type A. Darned if I didn’t drop some pounds, have less pain, improve my blood fats profile and inflammation markers, sleep better, etc. It started me on a search which eventually brought me to Paleo / Primal lifestyle and eating plans, as an applied Functional Medicine format. Diggin’ yer site, Mr. Sisson. Keep up the brilliant work.

  33. For heaven’s sake, these people are quacks through and through. I picked up their book years ago, before I found Primal living, and they suggested that the peanut is a good nut for me.

    Wait… What?

    Peanuts are legumes, beans. If they are SO flawed in their knowledge of nutrition that a peanut is a nut to them then I don’t need to taking any of their advice.

  34. Looked into this years ago and even own the cookbook. The reason I haven’t tossed it is because the recipes for Type O are really good paleo recipes.

  35. I followed blood type diet ten years ago (Type A) with great results. I was convinced by my chiropractor 5 years ago to go the Nourishing traditions/Weston Price approach and did so for three years. I gained 30 pounds, developed joint pain, rosacea and asthma. I was eating alot foods that were no-nos according to my blood type diet. (Dairy, bone broth, red meat, etc.) Two years ago I went back to the Genotype diet…I am clearly a Warrior and that is Blood Type A diet with fish and turkey, few grains, some beans, lots of plant material, soy and no fermented foods. I lost the weight and the asthma and roasacea cleared soon too.

    18 months ago, after discovering MDA, I tried paleo for a year: adding back the red meat, organ meat, bone broth, coconut oil, bacon, etc and fermented foods and cut way back on carbs trying to stay below 150 grams a day. It did not work for me. I pretty quickly gained ten pounds and my rosacea flared up and I felt crappy all the time. So I am back to a modified paleo diet concentrating these last 6 months on choices appropriate to my genotype, lost 15 pounds and feel great.

    SInce then I got a blood test that indicated I have the genotype that does well on very low fat diets: it made sense why I never could seem to get my metabolism to become fat adapted. I think even a few mutations in your genes can make what seems like small dietary changes make a profound difference in your health. Look at folks with PKU. I do miss my daily kefir water and sauerkraut though.

    I have heard Peter D’Adamo lecture to physicians and the science (which does not make it into the mass market books) seems pretty solid to me. Of course you can make anything sound good if you selectively highlight the research. But I do think there is not one diet that fits all and think many people could benefit something from this approach. All the blood type diets revolve around real food, you cannot follow the diet and be eating packaged junk.

    1. Great Testimony, I so believe that one persons food can be one persons poison and one persons vitamin/mineral/herb can be one persons poison and what works for one may not work for thee other and may make the third person worse. I support Dr.D’Adamo all the way because I tried a lot of diets and eating real organic food with each one and none of them worked. But when I started eating right for my Blood Type/Geno Type everything fell into place.

  36. I tried the blood type diet, and put my blood sugar on the roller coaster ride of its life. It was awful. The animal protein and fat recommendations were entirely inadequate, and the legumes and grain recommendations wreaked havoc on my health. Paleo is superior in every way.

  37. This is one of the first books I read and practiced before I found MDA. It just didn’t work for me.

  38. I went on the blood type diet a few years ago which led me to Paleo. Guess I’m glad I found the diet. It really worked well in the fact that it does eliminate processed food. It made the change to Paleo quite easy. I get to eat more stuff on Paleo. Type O’s shouldn’t eat pork. That was my biggest issue. I still always ate pork.

  39. So we have graduated from thinking the bumps on our head mean something (phrenology) to the bumps on our blood cells mean something. I think the same people just found a microscope. haha

  40. I read the blood type diet book many years ago. I have type O blood. I have found that I am sensitive to the major foods that he says are not good for O’s including the coconut oil. Hence I do great on paleo/primal diet.

  41. The blood type diet saved my life 13 years ago. I was a vegetarian Blood Type O non-secretor. Menstrual pain, joint pain, bloating, diarrhea, gas, skin problems, fatigue all got better or was eliminated. I am not totally strict with it now, but was tested positive for celiac’s disease and never have gluten. It is a bummer that the BTD suggested soy as substitute for dairy – and now, as is common for O’s, I am hypothyroid. My husband is a type A non-secretor and does well on grains and very little meat. I now soak his grains and beans and we drink herbal infusions and other herbs added into smoothies etc. We also follow many Weston A Price principles including adding in cod liver and butter oils every day along with bone broths, raw milk, and many fermented vegetables, kombucha etc. Basically, we eat a Blood Type Diet meets Weston A Price meets Susan Weed kind of diet. Many years of study and suffering and we are still learning and hoping to avoid the chronic diseases of our parents and grandparents. They all lived long lives with alcoholism, blindness, Alzheimers, diabetes, high blood pressure, and heart disease.

  42. I looked into the blood type diet and metabolic type diet before I found Paleo/Primal. Being type A I am currently thriving on the complete opposite of what is recommended by the blood type diet. If I eat too many carbs, I crave snacks all day (even too many fruits/veg). I’m doing my best ever with low carbs and high fat. Not thinking about food all day, never snacking between meals (don’t need it anymore)…so, blood type diet gets an F in my book. 🙂

  43. Generalities like the Blood Type diet includes some specifics but only enough to make it seem like there is something to it. It is like reading a horoscope.
    Blood type studies would be very interesting if there were any way to link blood type and the way food is processed in the body, but it is easier to market something that sounds plausible and gives people a sense of control over their lives than it is to research everything that needs to be researched.
    I have to include the universal constant: Entropy. Everything “dies” or gets “diseased” or whatever we label things as and no matter how we label it, it is constant. So, live well while you live. 🙂

  44. In 1998 Eat Right 4 Your Type was the first book to get me to question (CW and SAD) my diet, the first thing I read that said to ditch the grains, and my first stepping stone on the way to primal, so I appreciate it for that. It was also the first time I made the connection with diet to not only my body, but also to my brain. I followed it on and off for years with fair results (o+) until I read Wheat Belly and The Primal Blueprint/MDA in 2011 and decided that grains truely weren’t meant to be human food. My health and happYness did an amazing turnaround and I’m so grateful for this journey and this community. Without it, I would be alone in my quest.

    Sadly, I haven’t been able to help many others. On one hand I feel selfish keeping all this great information to myself when I actually want to shout it from the rooftops, but on the other hand I encounter so much resistance to the idea that bread might be bad and butter might be good.

    Dr. D’Adamo is as much a pioneer in this field as any of the rest of the researchers, authors, and bloggers and his ideas were groundbreaking for me.

  45. I had never given this diet a second thought and have been primal for the last two years. After looking at the PDF for my blood type (A), it makes so much sense. The foods that are supposed to cause distress (red meat, dairy, almonds) really do have a negative effect on me. Although this blog post was supposed to debunk the blood type diet, it may have had the opposite effect on me.

  46. Years back when I first decided to get in shape my mom was reading “Eat Right For Your Blood Type.” The very next week my wife was off to see her very well know Naturpatic MD and she mentioned to the Dr that I was reading that book. It was a normal day at the office there, lines all over the place. At 10:30 after already being there about 1 1/2 hrs I was deeply regretting going along for the ride and was closely watching the door. To my surprise when the Dr emerged with my wife I now had an appointment. So in I went with all those people looking at me, I could only imagine what they were thinking. Including the director of a famous cancer hospital who was beeing treated for Cancer. Moments later I was to learn the the book was fiction, that it was done by a ghost writer and that the superposed author lets just say was not the sharpest Dr in grad school, (being kind). The Dr I was now seeing was first offered to have his name on that very book. I was not somthing he could ever put his name on.
    So to conclude I never followed that diet followed this well know Naturpatic MD’s advise and was in the best shape of my life in 6 months, and lost more then 60 pounds. My blood works also backed up all results.

  47. I have been on the O BT diet for 5 years. I eat Paleo/BT. There are foods allowed on BT that are not Paleo (grains, legumes etc) so I skip those. The biggest thing is, the Paleo allowed foods that are NOT allowed on BT do give me problems. EX, coconut,corn, cauliflower,cabbage, mushrooms, PORK, eggplant etc. So I combine the two, it’s very easy. I have much improved health this way. I would have to say I’m far more Paleo but avoid my BT avoids. Works like a charm

  48. About 16 years ago, my naturopath suggested following the O type diet for asthma and allergy relief. I have to say it worked like a charm. It hit all of the foods with which I have problems – all grains except rice, legumes, and dairy.

    Personally, I would not use the “how much” guideline for portioning meats, fat, and carbs on this diet. If I followed the rules I would be starving, as it still did not have enough protein. Having a copy of the book, type A does have meat protein sources – certain fish and birds mostly, but they are not the same as type O. Peter D’Adamo recommends more plant food for type As than other blood types, but as I found, if you use the no-no list to eliminate problem foods it could be good. If you do not feel good, use your body to adjust the proportions.

    That said, when my digestive problems and my son’s started, I went to Celiac sites to find answers and one in particular had done a survey of its members to find out how many were type O blood types. Interestingly, more than 75 percent were type O (a lot more than the percentage it represents in the population), then next being A. B wasn’t even represented. The person who took the survey was a type O and he had gotten great relief following the blood type diet, which as Mark said is actualy a very strict form of Paleo.

  49. I am a type A, and a low meat diet just does not work for me. On the contrary, I do best on lots of fatty meat and as few carbs as possible. Not blood type diet for me.

  50. When I was in college, I accidentally ate according the the Blood type A diet, plus turkey and chicken and the odd fish. That is to say that I chose to eat primarily vegetables, some beans (mostly black), fruits, plus turkey and chicken and a bit of fish here and there. No red meat, no pork, no grains. I felt WONDERFUL, had boundless energy (24 credits per semester, an on-campus job, an off-campus job, radio shows, student org involvement and martial arts training 8x weekly) and got sick exactly one time. I did this without every having heard of ER4YT or Paleo or Primal, but because I felt good eating this way. When I came across the above sources, I had a “Huh. Neat!” kind of reaction.

    So, to me it seems rather like when I ask my 8-year old to explain an answer he has just give me. The answer is right, but the reasons are mostly wrong. Is it more important that the answer is right, or the reasons? In this case, both.

  51. Thanks for this post. I have been researching the Eating Right for your Blood Type and questioning it’s scientific validity.

  52. I can’t believe no one has touched on this yet…..type O is 80% of the population! It is a numbers game. He basically prescribed Primal for 80% of his book buyers… wonder he got such good reviews lol.

    1. Where did you get your numbers??? According to the numbers I was able to find, type O (+ and -) are only around 45%. There are almost as many type A’s in the US as there are type O’s. I suspect the numbers are fairly close world wide. This site lists the percentages in the US by type and Rh factor, so I added them up. Using those numbers, type O is 46.1%, type A is 38.8%, type B is 11.1%, and type A/B is 3.9%.

  53. Type O.Meat and plant-based diet.Sweet,I can gladly live with that.The dairy part is not clear though.

  54. Following the Blood Type Diet many years ago gave me the first jump start to a healthy way of eating and confirmed what I was slowly coming to on my own i.e. meat and veggies best, dairy and grains and beans not so good (I’m O). Out of curiosity, I began asking my patients what their preferred diets were i.e. “put your head out of the way and what does your body want to eat”. Certainly not everyone, but a significant number of people who found meat distasteful, or only wanted it occasionally (without holding any political/ethical ideologies) and love beans and rice and even tofu, and didn’t tolerate dairy invariably turned out to be A’s, people who could eat most anything, loved meat, dairy etc often were B’s and the O’s almost ALWAYS said bring on the meat! Also often found that the A’s were so happy with yoga and walking which bored to death the O’s. Mind you I wasn’t carrying out well documented research, just following my curiosity. I fell in love with paleo for all the reasons most anyone reading this would know: lost weight (the weight I put on when I ate vegetarian), have tremendous energy and generally look and feel better. Soooo I still believe if people trusted their instincts (not advertising, politics, etc) they will eat as nature intended and it wouldn’t be one size fits all, it would depend upon many factors, where they live, what kind of work they do, what is their environment, etc. No matter what your blood type paleo living offers a blueprint of eating local, pasteured, organic, fresh, sugar free, etc and that’s a great start for many people. My two cents today anyway.

    1. i am an O and i find yoga and anything slow in exercise does bored me to death! i have to do skipping to refrain from getting bored….my friend who is A cant seem to follow fast, hard cardio and benefits most from yoga! so true, even exercising is geared towards blood type

    2. I’m an O that likes exercise variety .. so I do a bit of yoga, running, strength training 🙂


  55. I have Chrones and whole host of othet autoimmune issues. My Gastro doc suggested the blood type diet when my digestive system pretty much ground to a halt. I stuck to it for two weeks and ended up witj severe stomach inflammation. Now I’m back to Primal with more than a few personally nrcessary tweeks, it’s the best I can do. It works. But in the end whatever the diet if something doesn’t agree with, don’t eat it. Excuse my spelling,I’m tyling on my phone with sausage fingers.

  56. I’m an O who benefited enormously from the ideas in the blood type diet back in the mid-90s when it first came out. I was a vegetarian, felt depressed, low energy, aches & pains – and I was only in my 30s! I had just started to wonder if what I was eating could have any relationship to how I felt when someone introduced me to this book. It literally changed my life! Of course, this was back when there weren’t GF donuts, cookie dough & pizza so it was a radical change for me. My husband is also a Type O, so when we got married, he was willing to fall in with my established dietary routine. By the time we discovered paleo eating earlier in this decade (thanks to a clean eating challenge & his CrossFit), I had already given up most grains and all recreational sugar, so it wasn’t a big leap. So for me, the Blood Type diet was like a “starter drug” that has taken me all the way to paleo, CrossFit and more energy, strength & well being in my 50s than I ever experienced in my 30s. Might not have worked so well had I been a different blood type, but at least it inspired me to make real connections between what I ate & how I felt, which some folks never get to.

  57. The ‘blood type’ diet worked very well for my family and me. Every existing blood type is contained in our family, and all of us have continued with our respective diets for several years, making changes when we wish. This diet completely reversed the severe reflux in our youngest child, and just in time before her permanent teeth came in; all of her baby teeth had been rotted because of the reflux. We also attribute the reversal of my husband’s reflux and the reduction of his cholesterol by 84 points to this diet. The great results were too obvious to ignore.

    We didn’t previously eat junky food, but because of ‘Eat Right For Your Type’ we all eat an even cleaner diet than previously.

    No two people are exactly alike, and if one is attuned to his body, he’ll know when a food makes sense for him. I wouldn’t go so far as to say the blood type theory is hokum because all six in my family have done very well with it. That said, I already instinctively knew that I needed to eat meat sometimes, and that eating a lot of grains doesn’t suit me well, which shouldn’t be true for someone with blood type A. I had already figured out that tomatoes and potatoes ‘light up’ my joints, I’m allergic to dairy, and I do well eating food grown locally and picked in season. Because I know my heritage and pay attention to what makes me feel best, I make adjustments. The blood type diet definitely aimed us in the right direction.

  58. I tried the blood type guidelines several years ago. I’m an “A”, so it basically got me off of nightshades and oranges…which nobody should eat anyway. I never went vegetarian (some meat is allowed), but did avoid red meat. It seemed to help a bit. What really, really made a HUGE difference was getting off of wheat last year. Within a week my gut started working right for the first time in my life.

    My husband is “O”, so primal/paleo is what he was basically doing, anyway. Honestly, just cutting way down on grains, losing wheat altogether, and avoiding sugar has done more for us than anything else. I think there are some good ideas in the blood type program, but it mostly seems to boil down to “avoid the things nobody should be eating anyway”, and vegetarianism is disastrous for anybody on anything other than a short-term, detox-type basis.

  59. When that book came out in the ’90s, I actually followed it for a bit and benefited from it. But then again, I AM type O which is pretty much a Paleo diet long before I knew such a thing existed. Eventually went back to my SAD ways thinking it was all hokey.

  60. I’ve always been interested in Blood Types and it never fails – every A blood type person I ever met is extremely food sensitive or if they don’t know it… they have health problems!

    1. My blood type is A+ and I am not, and have never been food sensitive – I have been tested for various food allergies and have none.

      I found MDA in June last year and after devouring this site and many other paleo/primal blogs I felt sure this was right, so I threw out everything processed, went shopping for real food and started my two children (age 3 & 5 at the time) and I on our primal journey.

      I have never felt or looked better and my kids are thriving. I wouldn’t want to try the blood type diet because I love red meat and instead of craving sugar (still happens now and again) I crave a thick, juicy steak!

      So I’m an A type that eats like an O type and I have never felt better or been so overwhelmingly satisfied with my life. I think I’ll stick with what I’m doing. 🙂

      1. Just from your picture you look like you have allergies. I’m serious.

      2. I am also an A – so I should be a vegetarian/grain consumer with some chicken/fish thrown in?? I was doing the healthiest version of the SAD for 6 months when I came across Primal. Lots of whole grains, veggies, fruit, very little meat (except chicken breast or white fish). Salads on a daily basis. Calorie restricted by about 500 calories. I dropped 10lbs and was becoming diabetic. Still had a big bloated belly and the spare tire. Then Primal came along. So apparently the Primal/Paleo diet works best for this A blood type, too.

        There seems to be quite a few As in the comments that didn’t do well at all trying to eat according to their blood type. I’ll stick with Primal….and I’m not slim. In fact, both my brother and father have been overweight/obese their whole adult life and both are A.

  61. I feel so left out…I’m AB+ No one to play with…
    I never tried it because it’s heavy on fish and I cannot find a strong enough word to describe how much I dislike fish…abhor…there ya’ go.
    I did love tofu though…and the body type description was pretty darn spot on.
    But, take away my pumpkin seeds and you’re gonna’ get hurt.
    Even horoscopes get some things right. 😉

    1. I am AB+ too, not very many of us out there for sure! I lost 60 lbs. and feel wonderful on the Primal diet, the blood type diet was a total bust for me, and I did it for years, kept trying to “believe” it was true, it made me sick, fat, and unhappy!

  62. I had been eating right for my type-O for years. However, the best thing I have done is to learn to listen to my body and what it’s saying after I eat something. I tried to be a vegitarian (before the blood type diet) and felt so tired all the time. I remember thinking in the car ride home from somewhere “I just need a big steak” so that’s what I fixed that night. Cured me right then. One of the other things I learned from my body reaction was “no more grains” since they gave me a stomach ache and beans make me gain weight. I still stay away from my “avoids” list since it’s pretty much a good list for me. I like eating Paelo now and my husband (type A) is benefiting from it as well. My son thinks anything that is healthy is yucky so we just don’t tell him he’s eating Paelo and he’s fine with it. Plus I love that I can put (grass fed) butter and coconut oil in my coffee and not need any sugar in it.

  63. I’m type A and clicking on the link, under body type it says “tends to be thin.” What?!? Even at my slimmest, I’ve always been “curvy.” I’m fairly broad shouldered for a woman. Bra shopping is done at the mall, some place where they’ll size me and help me find the selection in my size, which is fairly limited. Finding pants that fit right has always been a chore, because the ones that fit across the hips are loose at the waist, and should they fit both places, they’re still snug at the thighs.

    According to their site, I should avoid meats, except fish. I love red meat and bacon! Don’t seem to have a problem with it. I’m not that fond of fish, with the exception of both mahimahi and tuna (which are in the moderation section). I should avoid corn oil, but can eat corn in moderation. My digestion says to avoid corn, period, end of discussion. Many of the fruits they say I should absolutely avoid, I have no problems with.

  64. pseudoscience at its “best”…. 😛 as an A+, if i ate as prescribed i’d feel like the floor of a CAFO site!

  65. I am type A. I got so ill when I was vegetarian and instantly improved when I added fish and then meat. I then got ill again and continued getting iller and iller until I went primal. I am HFLC and it’s making me the healthiest I have ever been. I eat loads of meat and eggs, raw mature hard cheese, organic butter, fish, lots of green veg (not many crucifers though), some other veg, a little fruit (mostly apples and berries), wine, a little coffee, green tea and dark chcocolate. Very occasional double cream. I am really well on this diet. Mr Pigling is the same blood type as me and although he never got as ill as me he too has seen huge improvements on primal. The blood type diet would definitely not work for us!

    1. I am type A. I got so ill when I was vegetarian and instantly improved when I added fish and then meat. I then got ill again and continued getting iller and iller until I went primal.


      I think that (1) the author is totally wrong about when and how blood types came about and (2) by happenstance, some of the diets he recommends are OK for humans, but the diet he recommends for type As is terrible for most humans.

      Which has nothing to do with their blood type. OTHER gene combinations may be important though.

      Take a look, for example, at the jaws of ethnic Chinese vs. ethnic Australian aborigines. The former are much smaller. They’ve been eating rice and so on for a lot longer.

      Australian aborigines now — despite being the height of fitness when Australia was discovered — have epic rates of diabetes (as do my North American native ancestors).

      So are genes important to which diet a person can tolerate? I think so, and there are probably variances, on average, between populations. But the blood-type diet is claptrap.

      1. I think you fail to see what the author said:

        “These connections are worth looking into and deserve further study, certainly, but they have nothing to say about what diets work best with each blood type”.

        “In the end – and this might be the most important part of this whole thing – the blood type diet “works” because it eliminates processed food regardless of blood type, removes wheat from the diets of people with blood types A, B, and O (which takes care of the vast majority of the population of the world), and recommends that most people (type O is the most common blood type) eat a diet based on meat and plants with little to no grains, beans, sugar,and legumes. I’m honestly not all surprised that so many people get great results.”

        I don’t think he was saying this is set in stone but instead has some interesting points

        1. My point is they don’t work; they make it worse.

          The diet recommended for blood type A is terrible — note how many people, not just myself, on this thread say that that diet was awful for them … despite being blood type A.

          Whereas the diet for type O — low and behold, a Primal diet — worked wonders.

  66. At least they’re trying. But I think they missed the mark.

    I’m Type A. I agree with avoiding wheat and dairy (except for eggs) – I already discovered those sensitivities just by quitting them for a few weeks.

    But I’m finding a lot of foods that I find satisfying and energizing in the “Avoid Always” list (including ALL of my favorite fat sources), and a few foods that make me nauseous in the “most compatible” list. People say low-carb is hard to follow, I think this would be much more difficult.

    I like that they’re searching to biological markers that might help people figure out their best diet. And blood type is a logical place to start. But I don’t think they’re done.

  67. I don’t know about blood type, but I do think the idea that all human populations are, on average, exactly the same except for cosmetics can’t possibly be true in light of what is known of natural selection due to environmental pressures, interbreeding (with different hominid subspecies such as Neanderthals), and genetic drift.

    For example, I’m part North American native. European doctors wrote in their journals about how fit and healthy natives were when they first saw them.

    But now, the obesity rates among native populations is high and the diabetes rates are staggering — you find this pattern with many native populations worldwide. You also find higher rates of alcoholism specifically.

    It makes sense that what happened here is natives, such as my ancestors, were very healthy when eating a modern, Primal diet, but became even more unhealthy than whites do when eating a modern diet or drinking alcohol because they, on average, have not had time to genetically adapt to these same foods. In fact I’d say that’s almost certainly true regardless of how politically unpopular acknowledging any differences might be.

    So the takehome point for me personally about this is that I ought to be even stricter with a primal diet than someone whose ancestors exclusively came from Asia or Europe, where agriculture has been used for much longer. Finally, it may actually be harder for me to do so! I may have more of an innate tendency to be addicted to these novel concentrations of high carbohydrate and/or alcohol.

    I don’t seem to have a problem with alcohol, fortunately, but carbohydrates, yes.

  68. Nope! I tried that diet it doesn’t work. Didn’t make me feel better at all. I am blood type A, lots of soy? I think not…

  69. If you haven’t tried the Blood Type Diet, I’m sorry, but you don’t get to have an opinion. This is the only “diet” that not only helped me lose a ton of weight, get my energy back, sleep better and feel better, but my recurring issues with tendonitis and other inflammatory conditions were diminished or entirely elimintated. And it’s not a diet, I swear! I never understood why certain foods bothered me (like cauliflower, which I love but can’t digest) and after following this plan, I understand why. Those foods on my “Avoid” list are foods I either don’t like or don’t digest. Go figure 🙂 Thank you Mark for at least seeing how it can work and acknowledging that a lot of people have had success with it. To the nonbelievers – try it. You will be blown away.

    1. I’m sorry, but some of the recomendations don’t even make sense! I looked at the type A, my blood type, recomendations. It says to avoid cantaloupe, but can have melon (musk – among others) in moderation. Muskmelon and cantaloupe are different names for the same thing! So, aparently, so long as I call it a muskmelon, I can eat it? Under moderation, it lists Olives (green) and under avoid Olives (black, green, spanish). So green olives, okay in moderation or always avoid? Under moderation – spelt [a type of wheat], under avoid – wheat. Okay, so spelt is an older wheat variety and much easier for most people to digest than the newer dwarf wheat, but it’s still a wheat….

      Then there’s the whole avoid meats except fish (and apparently, in some cases turkey). I don’t care for most fish, and the few I do like are under the moderation column…… Not a diet I care to try. I’d be starving on it.

    2. As a type A I would have to be almost vegetarian – been there and done that years and years ago pre blood type diet and it did not work for me. My body craves red meat and I do so much better when it is part of my diet, so thanks but no thanks!

      Also, soy?! No way.

  70. We started exploring both the blood type diets and the paleo template at the same time early last year. We mostly followed the blood type diets for about 6 months. My husband and son are B. My daughters and I are O. We did feel better and noticed some changes. My husband lost weight. I stopped having joint pain and headaches. I was preggers at the time, so I was not losing weight. Looking back, the positives were likely more from reasons cited by Mark. After several presentations in the real food summit, we decided to make the shift to paleo. My husband lost 40 lbs in three months. I still feel less joint pain/ headaches. It is worth noting that we have found that some things about the blood type diet seem to match up for us. My husband tolerates all dairy and eggs. I do not. We have really reduced chicken, as my husband doesn’t usually feel good after eating it. Other than that, the rest of the recommendations are pretty paleo.

  71. In fact, if anything, it’s type A blood that’s the oldest.

    Well I’m A Rh Positive, and I know I do terrible on the high-carb, low-fat and protein diet recommended by this blood-type nonsense. I do much better, dramatically so, when eating a primal diet higher in meat and fat.

    So yes, Mark, I’d say your thesis is much more reasonable. The Eat Right for Your Type book is mostly pseudoscientific nonsense, to put it bluntly.

  72. Great de-bunking article! The only thing I’ve noticed for myself:

    I’m a ‘B’, and have noticed that never crave (or feel that good after) having Chicken – which my blood type would suggest. I do *awesome* on butter, pretty good on good cheese (w/ an enzyme), but, even raw milk doesn’t work for me. So, not the dairy-monger my type would suggest…

  73. Back in the day I thought the blood type diet worked pretty well for me. But frankly I am type O and it made me eat Primally so I got some pretty sweet results!

  74. I am type A. I did the BTD years ago, and because I was going from a rather SAD diet to this one, I felt really great, for a time. But since it was largely vegetarian and soy was allowed, I started having some difficulties. I ended up getting uterine cancer from the consumption of too much soy (well, it triggered it, there were other factors too). When I finally found paleo I found I had little trouble eating meats like beef and bacon, foods to be avoided by type A. It’s now in my been-there/done that file, never to be revived….

  75. Mark,
    I recently visited my local naturopath to look for some solutions to IBS and other discomforts of the digestive type. Well, she immediately recommended that I add grains to my diet. I was very disappointed to hear this, thought she was one of us. She told me that my urine and stool were both very acidic so therefore, I eat too much protein. Comments? Oh, BTW I am blood type A. What up?

    1. I was diagnosed with IBS in my early twenties. All doctors told me to eat more whole grain, more indigestible fiber, more veggies. Nothing, nothing, nothing worked – so I just dealt with it. (coffee and cigarettes did more for my IBS than those damn whole grains). Finally at 40 years old I went Primal (after following healthiest SAD for 6 months). Within 6 weeks I had a flat belly for the first time in my life. No more IBS, indigestion/heartburn, hital hernia; unbelievably embarrassing constant, nasty gas. I gave up bread three weeks prior and started to “empty out”. I eat lots and lots of meat, mostly red meat and my uric acid level was 2.4 (low end of normal). I’m an A. But I guess this is just my N=1

      1. The grains come back and so does the gas and the bloat and the feeling of carrying a brick around in my colon. No thanks. Thank you Mark Sisson for sending me on an unbelievable journey to health.

  76. Hi all.

    Yes, I tried Peter D’Adamo’s diet many years ago when the book came out. I felt ok, but I found that the plan was only slightly different than the way I already ate intuitively. I am a type A and I was a fairly healthy semi-vegetarian for many years. The only problems I had were associated (I now realize) with too much grain and processed starch consumption.

    Since going completely paleo a year ago, I have experienced more energy, better weight control and better sleep than ever. It seems weird to think that I may be getting in better shape than ever before, even while approaching my 61st birthday.

    Mark and I are in total agreement on this one. The evidence seems to point to removal of all grains, especially wheat based for all blood types.

    Grok on!

  77. Paleo is the way to go but the avoid blood type list is very spot on. Just because you don’t ‘feel’ a reaction, doesn’t mean you are not getting inflammed. EVERYTIME I try to veere off the avoid list, I get into trouble. Sometimes it’s not immediate but if foods are eaten often. I don’t want to believe it works, but it does. I think Paleo is just as important, getting rid of grains, dairy, legumes and sugar. I don’t follow the recommended amounts, just the not recommended foods. So the combo is great.
    A’s are a different story. Their diets have been refined since the book and most do far better on the genotype diet or the software.

  78. If I stick to the blood type eating it does seem to make me feel good. I am A- and I really noticed that when I started reading the AVOID foods that it does match up with things that make me feel bad (zaps energy or make me feel bloated/gas etc) It is mostly a vegetarian diet and so I am good with it. When I eat meat it upsets my stomach (which is why I stopped eating red meat a very long time ago and I found out about all the issues with Chickens having thyroid diseases etc). I do love fish (which some consider meat) and even the AVOID fish lists seem to be ones that aren’t as good to me.. funny coincidence..but I LOVE FISH if it is prepared properly (not fried) I am not a STRICT blood type eater, but I do pay attention and also the other health things in the book (like disease and what we are deficient in mostly seem to also have been right on) who knows.. NOW I try my best to eat organic, NON-GMO, gluten free and TONS of water, NO alcohol, fresh veggies & fruit…but I do not deprive myself with a once in a while awesome authentic italian dish from my favorite sicilian owned restaurant in town…. technically what I get there isn’t bad according to my blood type, but SO FATTENING!!!

  79. I’m type O, and all this time I thought I was the “original” blood type!. Darn. 🙂 Several people I know, including me, have the blood type diet book collecting dust on a shelf. It’s interesting, but I’ve pretty much learned what I can and cannot eat by trial and error. I also recently took the food sensitivity test called “ALCAT”, and it reflected what I’ve already learned about my body vs food with a couple of minor exceptions. Even without knowing I had an significant sensitivity to “shrimp” for example, it’s not a food I ever crave or gravitate towards. Blueberries for instance I really don’t like but ate them because they are supposed to be healthy. Turns out they are on my food sensitivity list. So it seems to me that I can trust my instincts and listen to my body! I recommend the ALCAT test as some people have some huge surprises. And what I like about it, if there is an extreme sensitivity, they recommend avoiding that food for a particular amount of time, then reintroduce it slowly, if you want to, and see how you do.

  80. My bloodtyp is 0 and I do very well on a paleo diet. My wife is boodtyp A and a vegetarian (but do samtimes eat fish) and she do also very well on here diet! I think there is samthink in the idea because different people seem to do well on different diets!

  81. Will not eat soy in any form…soy is garbage and not good for you

  82. It kind of reminds me of astrology, but for blood type and diet. Kind of fun to think about, with generalizations that work for everyone… but probably not true.

  83. I remember when the blood type diet first emerged (I’m A+), I was already on Carbohydrate Addicts so I knew that too many carbs (especially grains) were problematic. But reading all these comments just reminded me of a symptom I had forgotten about entirely that has gone away in the year and a half that I’ve been (mostly) Primal: heartburn! I utterly forgot about how regularly that occurred for me. And I think about a good friend of mine, who has terrible heartburn and acid reflux and who struggles with her weight (as do I). I can’t help but wonder if she would feel well if she gave up the grain. But it’s hard to do at first. Thank God for all the years on Carb Addicts, then South Beach–prepping me for Primal! (sorry I got off thread).

    1. Hey, South Beach prepped me for Primal too. Several of the concepts carry over nicely, so it made the transition easier.

  84. I totally tried the blood type diet. And it indeed worked, however I am type O, so like many of us who do so well on paleo or primal it was basically the same thing. I love my meat, veggies, nuts and fruits. To me if God made it I can eat it.

  85. Let’s hear it for the B’s !! Oh wait there’s like three of us 🙂

  86. Funny! When I first heard about the blood type diet I was offended because it said I SHOULDN’T be a vegetarian (and I was veg for a few years for ethical reasons). I did, however, wonder whether there was something in it when I didn’t succeed well as a vegetarian, whereas others seem to be able to remain healthy on a veg diet for years!

    1. It’s important to define “healthy”. Some friendly, low key questioning often reveals: anxiety issues/panic attacks, weakened immune systems, heightened allergic reactions, and under/over weight issues. Their children sometimes display issues with extreme moodiness (especially the boys).

      So compared to say, a diabetic eating SAD, they are healthy, but not to my much higher standards. The only vegetarians that I’m satisfied are actually healthy are those that receive a vast majority of their calories from eggs/butter/dairy and keep their overall carb loads low.

  87. I went on the blood type diet as recommended by my naturopath. I’m an o, and it worked really well for me! She also had me follow food combining rules. I’ve since added in dairy and forbidden foods like avocado, coconut oil, etc. and I do just fine with them!

  88. Thanks for clarifying that Type A is the oldest blood type. I’ve worked many a time trying to explain this to blood type fans.

  89. I always think of this diet when I see an avacado! I’m O type, and, besides eating Paleo-style, it says to avoid avacados. They’ve always given me a stomach ache, so in the back of my mind I used my blood type as justification for not eating them.
    Several people in my family have diagnosed Celiac’s and they are all O blood type. Probably a coincidence, but I’ve always wondered what Mark’s take on it was. Now I know! Great post.

    1. And pork doesn’t sit we’ll with me either…. INTERESTING! 😉

      1. I’m type O and avocadoes are an excellent food for me, easily digested without any gassiness, and most importantly they lift my mood when I feel a depression coming on, more so than any other food, and not in an addicto-inflammatory way either, I don;t crave them or feel any mental fog or anything (unlike say bread used to cause). Just my 2¢ 🙂

  90. I witnessed the book of the blood type diet (hardcover) used as a test subject during a Applied Kinesiology exercise. It failed on all 3 participants & the person then chucked the book saying it was BS! I laughed.

  91. I can’t believe how many people believe support this nonsense diet. just look at the many studies directly contradicting that diet on wikipedia.

  92. I have been on the blood type diet for more than five years, the paleo diet for nine months. In spite of Chris’ comments, it seem clear from this thread that some people are getting good results from this diet, including me. I am type B. When we went to a Chinese restaurant and ordered dinner for two, it was pork and shrimp. I ate it and was fine, but after I ate the leftovers the next day I thought I had fibromyalgia–I was achey and had difficulty sleeping. Incidents like that made me trust D’Adamo’s recommendations. I read “avoid” to mean you can eat it once in awhile.

  93. As a type A, if I had to eat the foods listed as suitable for my blood type, I would be permanently ill. The majority of the foods on the Type A avoid list are foods that I have never eaten anyway, and I still got sick (adrenal exhaustion), regardless of the fact that I never ate them! I am now 6 weeks into Paleo and can already see a difference in my health. I think I’ll just stick to Paleo thanks. 🙂

  94. Just imagine if a blood type A person (with a AO genotype) marries a blood type B person (with a BO genotype). They have four children. They could all be different blood types: one A, one B, one AB and one O. They’d have to have different diets according to the theorists. Yet they each share approximately half their genes with each other!

  95. Out of all the things I tried (vegetarian, vegan, raw foodist and, of course, Primal) Blood Type dieting was the least effective and enjoyable of my experiments. I’m type A, so it was like being a specialised vegetarian. By this I mean as a vegetarian I didn’t worry about which veg or fruit I ate. Is it a legume or bean etc – I didn’t stress about it. With Typing, I couldn’t go to any restaurant, or share a meal with anyone, because there was always something forbidden. Not to mention the turbulence if something unexpected happened and I couldn’t eat according to my prepared plan of action. Even if it did provide perfect health, I don’t know if it would be a sustainable lifestyle in this age. It created far more stress for me than any benefits it may have reaped, which were few. I felt tired, grumpy and very hungry. All the time.

  96. No diet can work if you need a laboratory to know how to follow it… People survived before blood types were discovered, didn’t they?

    1. Indeed they did, JKJ, but in the past we were attuned to our body sense and the variety of foods was smaller and less processed. We must learn to listen to what makes us healthy.

  97. I have dark brown eyes, so I must do best on chocolate!!

    Ha! I knew it 😀

  98. Before I went primal, I tried the Blood Type for my type A, and for two years I was constantly bloated, my dry skin was dryer than ever, and I waited & waited for “the magic” of great health to begin–I ended up in worse health than before I began, of course.

    After going primal, grain-free sugar-free dairy-free egg-free (I’ve been diagnosed with wheat- dairy- & egg-allergies), my skin is healthy & I no longer suffer from severely dry skin; I no longer suffer bloating or digestion problems; I look much, much younger than my age; the very dark circles under my eyes have disappeared; and I feel so very good all the time–yes, All The Time. As a matter of fact, in addition to feeling so very good all the time, I have developed an aversion to feeling bad and being around people with negative attitudes–I’ve cut them out of my life, and I now always feel calm, stress-free, peaceful, and just plain happy!

  99. When we can type and then extrapolate an optimal diet from the bacteria in our guts, then I’ll buy into individualised eating plans, but obviously someone with group A blood born 2 months premature with weak lungs, who’s had a childhood full of antibiotics, and raised in an overly sterile home etc will have fundamentally different gut bacteria and inflammatory responses (and all that carries with it) than the well-nourished full-term baby who was raised on a farm and whose health meant s/he didn’t have too many antibiotics as a child.

    It’s hard not to notice some people do well with some foods and badly with others (I feel better the day after I eat beef, whereas citrus fruit in any amount messes me up and causes cravings for more) but I think the contributing cause is personal gut makeup, genetics, and that blood grouping is too blunt an instrument.

    Also, it doesn’t as far as I know address the issue of rhesus pos/neg blood, a serious issue which can cause a child to die shortly after birth, which I would think is therefore a bigger issue overall with regards to antibody reactions than simple 4-way blood grouping?

  100. My Uncle does this Eat Right For Your Blood Type Diet often and has great success with it. He loses a lot of weight (naturally) and feels great because of it. He highly recommended it and still swears by it to this day. I bought the book years ago and so did my Mother. I hated the diet because I am type B and do not like the taste of game meats. I find it difficult to stick to something, even if it is successful if you dislike what you are told to eat. I find better success sticking to a primal diet and have lost 30 pounds now and feel awesome. I agree with Mark that the success of the Blood Type diet is because you are cutting out so much junk in your diet. Who would not lose weight and feel great after doing that? Its just simple logic really, cut the crap out, feel better.

  101. Hi! I appreciate the article. I have explored the blood type diets a bit. I have found that there are a number of foods on the avoid list for my type that I naturally do not want to eat, and others that do affect me negatively. (Type O) Same for my husband who is B, and several coworkers who experimented with it. There does seem to be something more to it than just eating whole foods and eliminating processed… what that is, I’m not sure. Perhaps we just don’t know what’s really going on in relation to blood type and there have been a lot of assumptions made.

    That being said, I do agree that a paleo diet is ideal for me at this point and generally a great improvement for most people… although lifestyle and health conditions need to be taken into account because it may be appropriate to have short or long periods of time meat-free or raw, etc. Thank you!

  102. I am type B and when I read the PDF attached, it says I should avoid COCONUT?????
    My diet revolves around coconut oil, coconut butter, coconut flour. My main fat source is Coconut, does anyone has any inputs on coconuts for type B?

    1. I do – trust what your body tells you is nutritious more than ANY book! 😉

      I do great eating more avocado to stave off depression, but according to this as type O they should be making me worse.

    2. I’m a type ‘B’ and used to eat a lot of coconut and avocados because they were considered ‘healthy’. When I read D’adamo’s books I decided to give up those foods just to see if there was something to it. I’m so glad I did, because I felt so much better afterwards. Now I still occasionally eat coconut (never did like avocados) but I am more in tune with my body and can tell that it bothers me. I’m a beleiver in the blood type diet combined with paleo.

  103. I was tested a couple of years ago for Apo E genotype. I already know that I am A+. I have never been able to digest red or white meats easily. Fish has never been a problem. After I got my Apo E results and found out that I am a 4/3 I NEVER ate red or white meats again. I continue to have fish. I decided it was now time to try Primal/Paleo. My biggest issue is I work at a brewery! So far I am loving the diet, but being creative every meal is not so easy. Keep up the great work you do, I look forward to your posts each and every day.
    Here is the link to Pamela McDonald’s site. I had the opportunity to meet her and that is what got me on the Apo E bandwagon. I would love to hear your opinion on this.

  104. Hey, what’s all the fuss about? The bottom line is: we are all different, never mind blood type (although it did work for me) the point is every one of us has a different body with our own health challenges, different foods create different inflammation in each one of us, what works for one may not work for another. The paleo diet/lifestyle can help eliminate many of these inflammatory symptoms and we feel better even though we each need to listen to and get to know our bodies and adjust our intake to what works for US, not for everyone out there. We are individuals and there is no cookie cutter plan for everyone.

    A great book to read and get ideas from is “The Virgin Diet” which isn’t that far off from the Paleo. The whole idea in the end is, do what works with you and only you . . . not the other guy!

  105. For me, another Victorian-style fad diet. Why? Because it’s based on a piece of knowledge slightly older than 100 years. If this were the diet to end all diets, most of our predecessors were unable to benefit from it, they had no idea there is such a thing as blood types. Fail for me.

  106. Hi, great article and comments!
    I felt vindicated when that Blood Type Diet came out, since I’m Type A neg. and had been vegetarian then vegan for many years. I was slim and healthy until my late 20’s, when things just fell apart. My hair got thin, I developed cysts in my ovaries and lymph nodes, was extremely depressed for many years and began gaining weight after drinking heavily and taking antidepressants. I started eating primal/ paleo in early April and my mood and energy levels are SO MUCH better. I also lost 15 lbs that I’ve been struggling with for a long time now. My theory is that I did okay being vegetarian when I was young and healthy, but eventually the deficit of necessary nutrients I was creating over that time caught up with me. I’m hoping I can reverse some of the damage done by continuing to eat this way–so far so good!
    So chalk up another (Type A) “NAY” for the BTD!

  107. Have you ever noticed that people say, “oh, I tried x or y diet and my joints feel better, my skin is great, and I have so much energy!” They’re all ditching the processed foods. Give the credit to blood type, paleo, primal, veggie, whatever you want, but quit eating the plastic food and you WILL feel better!!

    PS: Vegetarian for 2 years. It made me a type 2 diabetic. Not even lyin’! Love me some Primal.

    1. Absolutely, almost all diets including plain old calorie counting mean people will eat way less bread, pasta and biscuits at first, so that’s a major source of gluten reduced.

      Almost all forms of diet reduce flour products, veg oils and pulses as a side effect, but without knowing why they’re off limits they’re what we eventually crave and end up “cheating” on and then craving more and more, and the whole thing starts again.

  108. Concerning the comments about ancestral diets, here’s my experience: I’ve done practically every diet out there, from Slim-Fast to low-fat to Weight Watchers to Blood Type to Body Type to South Beach to vegetarian to raw vegan, etc., etc. in a desperate attempt to control my ever-increasing weight gain, to no avail. Although I’d been a skinny kid and easily maintained my weight through my first two kids, I suddenly started packing on the pounds and continued to gain for the next 20 years. It wasn’t until I read The Metabolic Typing Diet that I started researching ancestral diets–truly ancestral. (NO potatoes, despite my Irish heritage.) What I ended up with was a Primal diet. LOTS of meat (predominantly wild boar and venison), fish, seafood, some dairy, some veg (the ancient Irish used vegetables as more of a supplemental food than a staple), some nuts, and berries, apples and pears in season (wild varieties, of course). The root crops they ate were things like turnips and parsnips, rather than potatoes and carrots. I found this surprisingly similar to what I’d been raised on, although we did eat bread and potatoes, like most modern Irish-American families. I changed my way of eating after moving out because my friends kept telling me that I was a heart attack waiting to happen because of how much saturated fat I consumed. I spent a long, miserable, confusing period of years faithfully following each new “miracle diet” that came along, listening to all the “experts” and getting fatter, sicker and more depressed. It took hitting bottom before embarking on my ancestral diet; I figured since nothing else worked, I might as well go back to enjoying what I ate. I stuck with grass-fed, wild-caught, and organic meats and dairy (including lots of pork and salmon) and locally-grown and organic, seasonal veggies and berries–a bit more veg than my ancestors likely ate, but two years as a vegetarian had taught me to love my veggies). Imagine my surprise and delight when I discovered that, eating my favorite childhood foods, and strictly avoiding sugar, legumes and grains, I effortlessly dropped 70 pounds in under a year! During that year, I discovered The Primal Blueprint and modified my diet slightly to include coconut products, avocado, macadamia nuts, and dark chocolate, for variety and the health benefits they provide. I feel great, I look great and best of all, eating is an enjoyable, natural process again. Not only will I stick with a Primal diet for the rest of my life, I strongly urge my clients to adopt this way of eating as well. (My obsession with diets led me to become a holistic nutritional consultant.) I’ve seen similarly impressive results with the people I coach.

    1. Good for you, Suzi. I did exactly as you, save the occupation. Listen to your body, go unprocessed and experiment is the best advice in your post. Even as a child I knew that oranges and strawberries, (high acid) foods, were not good for me. Sadly, I think the skill to listen and avoid is very hard to do for many.

  109. I have read, and generally follow, an O blood type plan (as it is paleo anyway). But I saw an “8 constitution acupuncture” practitioner, and as a “pancreatonia” constitution body type my diet is mainly paleo anyway, omitting spicy, citrus and poultry. **shrugs**

  110. my whole family pushed me towards this diet when I started having all kinds of gut and hormonal issues. But being a type B, they suggest a high tolerance to dairy products and quite a few grains, and low tolerance for chicken among other things. Being that I am lactose and soy intolerant, I was hesitant. My body tells me that I do better with high protein content and some fiber, that’s what I stick to. Chicken isn’t the thing that’s killing me. I’m pretty sure.

  111. This really is a fascinating article. I think I may conduct my own “observational study” and determine if the above claims regarding susceptibility to disease within the different types ring true among my patients 😉

    I follow the blood type diet and in conference with many people find that I can often figure a person’s blood type by questioning his/er food preferences and senses, and feelings after certain exercises. I do have troubles with AB types but when confused between A and B I explain my confusion and suggest AB or one of the other. Still iffy though right a little more often than not.

    Also, excruciating pain in my left hip I damaged getting up from a table a little too short for me (thirty-five years ago) was much alleviated after about six weeks by eliminating wheat. It actually took almost nine months to become mostly pain free and to be able to walk long distances but the difficulties in walking began again a year latter when I was allowing one wheat treat a week on Fridays. I then went completely wheat free again and I could again walk longer distances. Surprisingly, after the original six weeks, the skin of my legs and my feet became sensuous for the first time in my life. I was also told at the time that I would need a complete hip replacement within five years, my hip bone was so deformed (the MD thought I had bone cancer but the scan said otherwise). I have been mostly pain free now for fourteen years and haven’t had a hip replacement. I am tinkering with my height sat fat raw/cooked paleo diet in hopes my hip might further improve or even regenerate.

    I listen to my body and avoid any food that doesn’t feel or taste right or that causes reactions. I was surprised that oranges and strawberries, foods that I have avoided since early childhood were on the list. They are too acidic Dr D’Adamo claims for O BTs because Os usually have very strong stomach acids. They have always hurt my stomach. However I have always loved lemons, limes and raspberries which seem acidic but turn out to be alkalizing. Limes and lemons I used when I had indigestion for the alkalizing-neutralizing benefits. I also think most people have had such crummy dietary habits they have not tuned into their body senses. I blame modern over-processed foods, denuded soils and poor childhood diets by well intending parents. I was persuaded early in life to eat Brussels sprouts and carried the behaviour into Sunday dinners in adulthood. The bag in the freezer was tossed with glee when I read the ER4YT book. Stinky, wretched little weeds they are. Same with cauliflower and, to a lesser degree, the iffy cabbage, though the heavier flavoured broccoli has always been my favourite veg.

    Allopathy disparages the possibility of Dr D’Adamo’s work but he claims that he has tested the lectins, for agglutination, in the laboratory on samples of all blood types. It would be very easy to disprove his theory and he is an incredibly intelligent and eloquent man (I’ve seen a number of his lectures) so it would not seem terribly bright of him to straight out lie. However, I suspect, nay I know, the majority of allopaths I have met have been so indoctrinated they have no idea how locked into a box they are and are dismissive to nutrition in food as having much importance to health.

    Mark, I appreciate that you at least gave credit to the strengths and weakness of blood types when it comes to diseases. Bubonic plague is another disease that is claimed to be particularly deadly to O blood types. Such may have been the reason type A suddenly became the dominant blood type in Europe up until the Twentieth Century when O blood type again began to make up the largest group, world wide, I believe.

    Thinking outside the box is not a common trait throughout our species, Mark. It may be a sense favoured by far less than ten per cent of the population. Creative thinking, reviewing accepted ideas and those of vocal specialists and advocates (including oneself and one’s own biases or conclusions), challenging conventional wisdoms, would have been quite a detriment, in the heat of battle to our survival when herd mentality and xenophobia were necessary for the survival of our species. Today, with modern propaganda, I suspect it is the reverse and we all need to question conventional wisdoms and especially the waggling fingers of the medical professions and scientists. Prevailing trends often are the source of their incomes and that, for the empowered, is often an underlying thorn preventing any discussion of conflicting ideas which are seen, possibly feared, as threats to personal beliefs or assumptions. I call upon the histories of Galileo and Semmelweis to support my case. One was harangued by religious dogma and the other by the profession in which he lived and of his own steadfastness, over-exuberance and strong bearing.

    I don’t expect the closed minded to give a newts whisker for any thought or notion that challenges their worlds, but I do expect the creative thinker who thrills when a personal wisdom is challenged, to keep an open mind and willingness to ponder the possibilities of even the most foreign and challenging of possibilities. If one’s mind is made up on either side and all edges to the possibilities of alternative thinking such as (—alien beings, speeds far in excess of the speed of light, 911, questions to climate warming, the source of the sun’s energy, the idea that science cannot explain the possibility of ping pong and other sports at such speeds, the possibilities of an ever-being, conscious universe or that consciousness, self and mind might reside outside the brain—) let them sit in the comforts of their knowledge. All ways of thought have their purpose in the progress and success of our species for both keep the other grounded and challenged at appropriate times.

  113. several years ago I went to a bioentergenist who told me about the eat for your type book, which I purchased; while I don’t subscribe to the diet based on the book, what I found very interesting was most of the foods listed, which I should avoid, were foods that I was not eating anyway because I did not feel well after ingestion . .

  114. I notice that three out of the four profiles suggest eliminating wheat. That seems like it would contribute a whole lot to successes, regardless of whether the rest of the science is baloney.

  115. My question is I’m AB neg and I’ve been eating fairly strick paleo..95% for a year. I’ve gained gained 45 lbs in 10 months. What’s going on. Is paleo not for me.

    1. My first thought was “you are kidding yourself” I find it hard to believe anyone would gain 45lb from eating paleo, but then when I thought about it it seems to me that there are several pitfalls for the newbie. Its hard to say without knowing what you are eating in a day but here are some common errors.
      First portion size does matter. Check how much protein you are eating – it may be too much
      Are you eating a lot of fruit, nuts or dairy? cut them out for a couple of weeks and see how you go. ditto root vegetables.
      Are you eating processed meats? Sausages ham jerky salamis ets. These can contain a lot of sugar used in the processing.
      Are you still drinking alcohol? this can affect fat burning
      Are you eating high protein bars or shakes. Cut them out – artificial sweeteners can play havoc with your metabolism.
      What are you 5% non paleo foods? If you are ‘good’ all day and then eat a bar of chocolate every night then you are kidding yourself!
      Lastly some people are more carbohydrate sensitive than others. Mark’s “sweet spot” of 150g carbs for effortless weight maintenance would see me piling on the weight. I do better on 50g a day. You should investigate low carb eating and tweak your diet and see if this helps

      Good Luck!

      1. Ok first not a paleo newbie second my meals look like this….. 2 eggs…breakfast….lunch chicken broccoli… Dinner is meat and veggies. pretty basic. I drink tea and water. I use butter and spices for flavor.
        Thanks in advance.
        I don’t like fruit so its pretty rare for me to eat it same with nuts

  116. This is very interesting. I am A+ and for years followed the weight watchers diet – very little red meat, low fat everything,plenty of legumes, and vegetables and allowed quantities of bread and potatoes etc, basically I was following the diet recommended for A blood type. I struggled with my weight, was obsessed by food all the time, felt tired and hungry all the time and suffered from roller coaster blood sugar highs and lows and major cravings, but ,hey, I was eating healthily!. As I grew older it became more and more difficult to stick to the ‘healthy’ eating plan and my weight crept up as I started to binge to satisfy cravings and just to get a feeling of not starving all the time. One day in Borders I browsed through a book outlined the basics of low carbohydrate eating and described my food/eating problems to a T. This started me on Atkins/low carb and now Paleo ( the complete opposite of A type eating) and all the above symptoms have disappeared. After a year of trial and error I find I do best on a low carbohydrate (not more that 50g per day) with no grains, or legumes, though I do eat limited dairy. I’m never hungry, don’t need to snack, I have lost 5 kilos and have abundant energy. Had I stayed on the diet ‘suitable’ for my blood type I have no doubt I would now be fat, miserable and sick.

  117. The Blood Type Diet worked well for me, basically because the type O diet is paleo/primal eating!!

  118. I was pretty skeptical about the blood type diet at first and although there is no solid evidence proving it, I seem to not agree with everything that is a no-no for O blood types. Beginning a primal diet I could eat anything really, but as time progresses I began to feel sick after eating eggs, pork, avocados, tomatoes etc. All things that are not good for the O blood type. So who knows, maybe there’s some truth in there somewhere.

  119. A friend (O type) and I tried this diet a few years ago before I’d even heard of celiac or paleo or anything at all like that, when I started having my first serious issues with IBS and massive weight gain. Since my mother had always told me I am A+, I went with the grains and less meat, and my friend did the more or less paleo option. Unfortunately, I only found out a few months ago that I am actually O type.

    I remember many conversations that started with my telling her I wish I could do her diet, that I just felt like mine is wrong for me. Indeed, I eventually abandoned mine and went for a strict macrobiotic diet and Atkins. Meanwhile she continued on the O diet and did really really well.

  120. In the old days – before people knew which blood type they were – they just had to guess; I’ll presume I’m B+ and eat according to that – imagine all the confusion back then!

  121. Ive tried and tested the blood type eating plan… As a type O I thrived on it for obvious reasons.. I was a real believer in it until I understood more about evolution and anthropology then its philosophy never really jelled with me or made sense…. One thing I did find interesting is that some of the foods like the particularly nuts were things I naturally craved… and certain foods on the not to eat list I was already naturally avoiding as the didnt agree with me..,…. any way its all grok style these days which is serving me just fine!

  122. This is about the only thing I have ever disagreed with Mark on. I used to feel the same as him about the blood type diet, until after my own challenge with my health the past 2 years, and discovering what worked & what didn’t. For years, patients asked me about the blood type diet. I would tell them just follow a “healthy” diet with organic food. I finally read the book “Eat Right 4 Your Type”, studying Dr. Peter D’Adamo’s work at the urging of my father. His health made a huge turn-around & was having good success with controlling his digestive & ulcer issues with the diet. Scientifically, it made complete sense. The blood type diet is based on science (however, Dr. D’Adamo’s origins, IMO aren’t based on science, but merely observation & opinion. I don’t agree with that part).

    Me, being blood type A, followed a different pattern. After years of eating what I thought was good (mostly paleo), enjoying good health, then seemingly to go downhill suddenly, I followed the blood type recommendations strictly. It made all the difference in the world. And the first time in my life, I was able to loose weight, effortless (after struggling with this for years, even while following a “healthy” diet & exercise).

    I have noticed people who disparage or put down the validity of the blood type diet are those who have not read the book & have no scientific understanding of the basis of the diet. Their comments are made out of ignorance. I am sure Mark has studied the diet though before blogging on it. He does make some good points. However, Dr. Peter D’Adamo, the author of the diet, has done extensive research on blood types & diet, going far beyond basic scientific studies, mostly likely the ones Mark is referring to. Dr. Peter D’Adamo is the world’s foremost expert on the subject. He has done decades of research & work on the topic. He is far more qualified to make the recommendations he does than anyone else.

    The blood type diet is scientifically based, sound & it works. Marks conclusions are too simplified to be taken scientifically.

    With all that said, I appreciate Mark’s opinion, as well as his diligence in freely sharing with all of us his knowledge & expertise. He is truly a remarkable person.

  123. I spent 5 years in and out of several doctors offices, gastroenterology offices, ER’s, and urgent cares. All of my tests came back normal. Everything they told me to do failed. My body finally reached a point of constant pain. My dad flew me out to AZ to see doctors by him. When I arrived he suggested that I try the Blood Type Diet just for the heck of it. One week later ALL of my problems were gone! I ended up not even seeing doctors by him since the diet was working so well. I’ve now been on the diet for over 3 years. I deviate occasionally…esp for potatoes and peppers that aren’t good for type A. However, I always pay the consequences. I’ve learned that different foods affect me in so many different ways. My favorite learning experience is that if I know I’m going to deviate from the diet, I load up on highly beneficial foods before and after and the consequences are significantly reduced! Considering that I’m in some form of pain and/or discomfort every time I deviate from the diet I will most likely be sticking with it for the rest of my life. It feels so amazing to no longer be afraid to eat and to be able to control the pain and discomfort!

  124. Any diet that would have been impossible to follow for the majority of human history and that requires blood typing and other tests is highly suspect to me. As is any diet that requires counting calories, taking careful measurements of resting metabolic rate, etc. Making people believe that they need to be treated like science experiments in order to be healthy is problematic, makes them dependent on somebody else’s judgement, and may cause them to ignore clear signals that their own body is giving them (“I’m hungry all the time.” “I feel really tired.” “When I eat X my stomach hurts, but it’s in the diet so it must be good for me.” “I constantly crave meat but I know it’s bad for me.”) that something is wrong. I’ve unfortunately seen it even among my former coworkers at the health food store, who should have known better.

  125. I’m actually doing D’Adamo’s Genotype Diet, an update of his blood type diet, after being paleo for 3 years, doing the bone broth, organ meats, fatty cuts, grass fed, what have you. I was seriously invested in paleo and learned everything I could but it wasn’t working and my health got much worse than it had been before paleo. My health still isn’t perfect, but I’m way healthier and happier now being mostly vegetarian (I eat lots of fish and eggs) than I was on paleo. I’m glad I did paleo, though, because I have still held on to a lot of what I learned about how to live.

  126. I have followed the blood type diet and still do to about 90%.
    My results where absolutely incredible.
    Everything changed for me to the better.
    I tested around with food after a year following it pretty strict and I was amazed about the effect by the ‘to avoid’ foods.
    I am blood type A and I reckon anybody following that diet will have a similar effect though.
    Since many people watched me transform over a short time I have guided years ago about 20 people with the blood type diet as well.
    Most people had seen great effects after a short time but ALL blood type A’s had the most profound change and transformation within 2-3 weeks.
    I reckon it is worth to try it out and see for yourself.
    If you really want to know all details about the diet tailored for you personal than you should go to a nutritionist who offers food related blood analysis.

  127. I did try the blood-type diet for a while (I’m O type) but I found it a little complicated and inconvenient to follow at that point, simply because it opens too much restrictions overall: even among spices, vegetables, meat, fish and fruit…

  128. I did try the blood-type diet for a while (I’m O type) but I found it a little complicated and inconvenient to follow at that point, simply because it opens too much restrictions overall: even among spices, vegetables, meat, fish and fruit and so on…

  129. I did try the blood-type diet (I’m O type) for a while but I found it a little too complicated, simply because it opened too much restrictions overall: even among spices, fruit, vegetables, meat, fish, and son on (I’m Paleo now)…

  130. I think that BTD attempts to deal with the two major, obvious challenges to the calories in/calories out mantra.

    1) There are people who are of ideal weight, have strength and stamina, plenty of energy, sleep well, etc etc and so forth – and have these markers of good health in nearly every pattern of dietary observance a person can name.

    2) The human gut is the next unexplored frontier.

    Blood type, secretor status, and genotype all attempt to address these factors. Somewhat less efficiently than DNA typing the bugs living in our gut but still trying to address these challenges.

    Why DO some people thrive on a more or less vegetarian diet while others get terribly ill? Why do some people experience great relief from illness and inflammation on an animals and fat diet, while others find they become far less healthy?

  131. I did try the blood-type diet (I’m O type) but I quit on it, simply because it opened too much specific restrictions (a little too complicated), even among fruit,
    vegetables, meat, fish, spices and so on, so nowadays I’m Paleo, which was a very natural transition from one to another 🙂

  132. HI,
    I followed the bood group diet meticulously for just over a year. My symptoms were a deep tiredness almost in the bones that had not responded to sleeping and resting and any type of therapy.
    Within 2 weeks of the diet (A blood group) I already felt significantly different. So I stayed on it. I also agree with the types of exercise suggested, the milder types, Yoga and meditation. I used to go jogging with an O group friend. I was wel done after one round and they needed 4 to get the same results!.
    I recently tried to eat a more O group diet and it does not agree with my body. It makes me tired and heavey.

  133. Before the discovery of DNA, scientists used blood proteins (the human blood group systems) to study human genetic variation. Research by Ludwik and Hanka Herschfeld during World War I found that the incidence of blood groups A and B differed by region; for example, among Europeans 15 percent were group

    Excerpted from Wikipedia

    “B and 40 percent group A. Eastern Europeans and Russians had a higher incidence of group B; people from India had the greatest incidence. The Herschfelds concluded that humans comprised two “biochemical races”, originating separately. It was hypothesized that these two races later mixed, resulting in the patterns of groups A and B. This was one of the first theories of racial differences to include the idea that human variation did not correlate with genetic variation. It was expected that groups with similar proportions of blood groups would be more closely related, but instead it was often found that groups separated by great distances (such as those from Madagascar and Russia), had similar incidences.[2] Researchers currently use genetic testing, which may involve hundreds (or thousands) of genetic markers or the entire genome.”

  134. My cousin and I are both B+. She has been on the blood type diet for about 3 years and dropped 40 pounds. I tried explaining to her that she lost the weight because she gave up all processed foods and started “eating clean” but for some reason she still believes it’s because of the blood type diet. Can’t get through to her. Oh well… at least she’s eating healthfully now. 🙂

  135. I did ER4YT and followed it religiously for about 9 months. I’m O and I felt the most amazing I’ve ever felt in my life. I fell off due to life pressures and travel. I’m now recently diagnosed with endometriosis and have been feeling like crap for such a long time, and was in a vicsious cycle of eating crap and craving it and so on. I knew I needed to get back on it, and when I talked to a friend, he pointed me to this website. I’m so excited to have this resource and to feel amazing again. It’s all so simple and just makes sense. Thanks you!

  136. I am type A, and the vegetarian way of eating does not work for me. Grains make me bloated and give me stomach pain, as does too much dairy. Fat, and lot’s of it, is what works for me! Coffee with heavy cream keeps me going for hours and I do not have to make breakfast!

    When I was on Atkins (about 8 years ago), I felt the best I had ever felt health wise, but I allowed myself to be derailed by people in my life telling me how bad “all that fat is”; I knew it wasn’t, but I hated having my co-workers staring and making the tsk tsk sounds at lunch. I lost weight, slowly and steadily, and felt good but still caved in to the masses.

    The best thing the government has ever done was made the announcement that as far a food plans go ONE SIZE DOES NOT FIT ALL, so at least now I can use that nugget when my (new) co-workers want to know why I only eat a meat patty at lunch lol.

  137. Quite a few comments on this one…. Dr. D’ Adamo’s anthropology can be questionable at times, but the blood type food values are ultimately determined by INDICAN testing (measuring the digestibility of a given food based on levels of rancidity specific to the ABO makeup in the gut). I have been following the ABO diet since it hit the NY TIMES best seller list back in the 90’s, and have had nothing but GREAT results. I’ve read the DADAMO and MDA books, and don’t see much difference between what they are both prescribing (sometimes, I will see a condemnation of a particular food on MDA, only to see an exception article later on (EX. RICE), which usually lines up with DADAMO’S original take.) I have a deep respect for both parties, who ultimately advocate the return to natural foods and healing. God Bless.

  138. Quote: “I have noticed people who disparage or put down the validity of the blood type diet are those who have not read the book & have no scientific understanding of the basis of the diet. Their comments are made out of ignorance.”

    That is so true, and so very sad.

    Like other doctors who have posted here, I too have informally asked my patients over the years about their diets and what foods work best for them. I have invariably found that people who do best eating a lot of vegetables and not that much protein (especially not caring for red meat very much) are always blood type As. They also prefer yoga and other lower intensity exercise.

    Blood type Os however always report that they do best with a lot of meat/protein and regular intense exercise. I can’t even tell you how many type Os I have known who tried a vegetarian diet because they thought it was “healthy”, and it ruined their health.

    I have read Dr. D’Adamo’s books, and further looked at a great deal of his scientific research which is extensive and very sound in my opinion. Some of the belligerent comments here likening it to astrology are downright offensive considering the years of research that has gone into the work, and how much it has helped people.

    Part of the problem though is that the Type A plan that was described in the original book back in the 1990s did not take into consideration the Type A subgroup that was later found to need significantly more protein than other Type As.

    The Blood Type diet was further refined by taking into consideration Secretor versus Non-Secretor status. Knowing your Secretor status can result in significant refinements of the diet that will make it even more effective. For example, I am a Type O Non-Secretor, so avocado and coconut oil is fine for me, but an avoid for Type O secretors.

    Secretor/Non-secretor was discussed in D’Adamo’s later book “Live Right for Your Type”, which I think was released in or around 2007. If anyone would like to try the blood type diet, it is very worthwhile to order the secretor test.

    The diet recommendations can be even further personalized for the individual with the SWAMI software and GenoType testing. I haven’t done this yet, but plan to.

    I can understand that people posting here are very attached to the idea of Paleo for everyone, but I can tell you from practice that it is not quite that simple. I’m a type O, so I am much closer to Paleo than vegetarian/vegan… but there is so much more to optimizing one’s diet in a way that truly fits the individual. In my experience, Dr. D’Adamo’s program is the closest you can get to personalizing a diet program for someone. (Although I suppose there are rare individuals who have chronic food allergies that remain even with strict BTD compliance – so they may need even more customization.)

    By the way, I took a look at the Type O PDF listed in the article above, and saw that it was compiled by someone other than Dr. D’Adamo and it doesn’t take into consideration Secretor/Non-Secretor status. (Or Dr. D’Adamo’s GenoType groupings.)

    If anyone is reading this and wants to try the blood type diet, they can order a home blood test kit (if they don’t know their blood type) and the saliva secretor test. Then you can just check the database on to see which foods are beneficial, neutral or avoids. For anyone who is having major health challenges, it would probably be well worth it.

  139. Here are my facts, since we seem to be compiling a nice database of anecdotal evidence here, are as follows:

    My dad is o+, my mom is B-, I have one sister who is O-, and one is B+. I have never known my blood type and every test I have had for it has been inconclusive. Dad and both of my sisters prefer a high-carb vegetarian diet with fish and do well on it. Dad and my type O sister like running excercise, but my other sister prefers weights. Mom exists solely on grain, potatoes, and dairy, with fatty meats sometimes. She does no excercise at all. Her health is surprisingly good.

    I gain weight and feel terrible if I eat either mom’s diet or dad’s diet. In fact, I did nothing but gain weight all my childhood. When I started to cook for myself, I tried many diets and gained weight on all of them. Eventually, my doctor told me to try keeping a log of foods and how they made me feel. Eating foods that make me feel good has helped me start losing weight. Not huge amounts, but 40 pounds in two years. Here are some of my results:

    Happy foods: wheat, spelt, spinach, cucumbers, tomatoes, chicken, beef, pork, Lima beans, kidney beans, butter beans, hummus, lime, milk, yogurt, wasabi, seaweed, mushrooms, yellow squash, dark chocolate, onion, cabbage, pickles

    Misery food: sugar, honey, green or wax beans, broccoli, garlic, rice, cheese, oats, fish, seafood, soy, Brussels sprouts, most fruit, lemon, corn, fatty meats, eggs

    I have noticed difficulty digesting fats in general. For excercise, I prefer swimming, aerobics, walking, or an orbital stepper. I actually get weaker when I try weight lifting.

    So, what blood type am I? You’re welcome to speculate. i doubt I’ll ever know, and I’m not sure it matters. By keeping a simple log, I got a diet that works and it cost me nothing.

  140. It seems there is no way to edit a post, but I can’t believe I forgot potatoes. Nothing makes me suffer more than garlic, but potatoes come close.

  141. I started the er4yt eating plan almost a year ago. I began by adding in the “beneficials”, leaning on the positive aspects of the plan and I have to say the pain in my knees was the first to go! What a great side effect. I am so happy to be going up and down stairs like a grown-up again! It’s working for me, I’m happy about that.

  142. I have been on the blood type diet twice and done very well with it! The paleo diet conflicts somewhat with the A blood type, but from my own reading of the blood type diet and reading some of the comments above , the blood type diet works, but you still need to find out which foods from each group work best for you. Yes, we are a high-plant based group and “vegetarian”, but we are only cutting out red meat and shell-fish and some KINDS of fish and some KINDS of items from other food groups – not the whole lot, in most cases. I am lactose intolerant and get constipated from wheat. Tomatoes and/or kidneys (chili) gives me Restless Leg Syndrome. Those are things I know bother me, so if I choose to cheat occasionally and eat them, I have nobody to blame but myself if I get a flare-up. Potatoes and wheat sometimes give me chest pain – another reason to avoid.

    Regarding Canadian Blood Services (since Red Cross no longer looks after blood), I once read a hand-out there that actually talked about each blood type, the type of exercise we should do (just at the blood type book does) and that A’s are vegetarians. I don’t know if the got their info from the good doctor, but it’s all about chemistry.

    I’ve lost a huge amount of weight on the blood type diet and don’t find it that difficult to do when eating at home. Our family of four is all A, so it’s not a big issue. Hubby refuses to give up his cheeseburgers and finds they balance his blood sugar (Type 2), but he has to buy them. He will eat what I cook unless it’s got tofu in it, and it’s rare that I use it.

    Incidentally, when I started my blood type diet in January and did a detox kit for the first 10 days (using blood type A foods only), I lost around 10 lbs., but in the first three weeks (cutting out ALL sugar, dairy and wheat) I lost six (6) inches off my waist in THREE WEEKS! Yes, the Paleo diet likely could have done that, too, but historically – when I eat out – I buy fish and chicken. Maybe it’s like out “colours”: We naturally choose what our body wants – when we’re paying attention to how it reacts to certain foods.

  143. I got interested in this diet several months ago because of our family’s history with heart attacks. After 3 months on this diet ( type A ) my cholesterol dropped 41 points and triglycerides dropped 100 points , both are below the normal targets of 200 and 150 ( I think those are correct numbers ) . Weight has never been an issue for me as I am an avid bike rider ( 100-200 miles per week ) but I still have dropped 5-8 lbs on this diet. Do I enjoy this diet ? Not really but the bottom line is my body does not process meat efficiently, it just doesn’t. I have adapted and accepted this reality. If your reading this have a burger for me ????

  144. I should start off by stating that I have type 1 diabetes and Hashimotos disease- been low carb for yrs ( 30grams or less a day) I felt better because my blood sugar control was amazing, but did not feel good enough. I went off all packaged foods, grain, and dairy….better, but not much better. At that point I was eating a lot of greens, EVO, coconut oil( the holy grain for thyroid patients) peanuts, coconut flakes, almonds, meats were mostly poultry or pork ( I know what I was eating was very pure too). At this point both my husband and I decided to give he blood type diet a go! I am Type O-He is Type A. This made it more fun because his diet would be quite different than mine. I made the choice to really focus on the “healing” foods on my list and took out the forbidin coconut/peanuts That I used often and added pumpkin seeds and lots of red meat. My husband ate much lower fat-much higher carb and foods like pineapple, oatmeal, molassas and peanut was a staple-he has IBS and has has issues from almost birth. Our health issues fit our blood types too-Found that interesting. RESULTS after 1mth- I can honestly say I felt great-really. I swing between a siz 4 and 6 and always fight to keep weight off-that mth I was a 4 without fighting or swinging back and forth like most mths. I tried adding the coconut and peanuts back and felt bad again- I am going back to it as we speak-I tried more variety and it never works out. I don’t love red meat but my body really responds well to it. My husband lost weight and for the first time in his life was not running to the bathroom after eating. The pineapple really helped hid stomach. Interestingly, my husband has stomach issues when he follows a diet like mine. That is how it went for us! Just wanted to share!

  145. Give me any person and put them on their blood type diet and see the shift in my friend need to look at the fact and results from an inspirational bloke who has devoted his life to helping people out of their misery..

  146. Its the blood type diet that led me to a Paleo Diet Lifestyle!

    I’m an O non-secretor, and when I started following it with discipline I started having days of feeling better than I ever have in my entire life and I’m 33! 33 years of living in an ADHD, fog headed, anxious looping nightmare made me get there was something to the blood type thing for me. I’m a total nutrition and biochemistry nerd because of the challenges I’m working through which led me to further study… upgrading/integrating Paleo.

    What Mark says makes sense! I like using the O blood type non-secretor diet recommendations because they complement and integrate with Paleo from the O blood type perspective. I also lean more towards the Paleo based approach because I’ve gotten even better since starting to integrate it in combination with medical testing and working with an ND. It also just feels best for me and is better researched in certain Paleo tribes. This article is a great example!

    I’m a huge fan of solid scientific research that backs up experience and intuition. It is my truth when you put these things together you really have something real!

  147. I have been on the A type diet for 3 months, I have dropped 15 lbs. I am off my acid reflux meds. My IBS is gone and I really feel better. I am not a strict follower of the diet. I still need comfort food sometimes but have to take a Prilosec if I eat the no nos. Snacking is hard but I now make turkey jerky. It is getting easier to eat the real food everyday. Stay Healthy

  148. Each new blood type through ‘evolution’ represents a genetic manipulation by our little grey friends from Zeta Reticuli who travelled 39.5 light years to accelerate our development here on earth. Otherwise we’d still be living in caves. Blood groups have nothing to do with diet: that’s just wishful thinking by the sick and those who have books to sell. There is NO scientific evidence for D’Adamo’s blood-group diet. Anecdotal tales relate improvement, sometimes, from following elements of it but that is just ‘a change being as good as a rest’. To eat healthily: eliminate grains, sugars (except raw honey), chemical pollutants, xeno-estrogens and GMO. People are lazy and always want a quick fix; the blood-typing diet is not it.

  149. I would love to hear from more B’s that have tried this “diet”. I find it interesting that the book suggests that us B’s have issues with immune diseases, which is true for me. In fact, most of what is said about type B’s is spot on for me. A couple of months ago, after being diagnosed with a second autoimmune disease, I made the decision to go gluten free. I’ve felt better, but still not feeling great. Continuing my search here to get to overall health and wellness…

  150. I feel better on the type A diet.
    Chalk it up to whatever you like.
    I’m happy with it though.

  151. Friend of mine has been on this diet for 15 years. He suggested I look into it and I found my way here. Personally I was very skeptical when I heard about and my research has bore out to my satisfaction my doubt.
    As for my friend,he said it turned out he was sensitive to wheat. He stopped eating wheat and followed the diet and got better. Not really the blood type diet that made him well, but it did help him find out what making him sick and get him well.

    1. Actually his more recent work (Genotype Diet) has As eating alot of fish, turkey.

    2. That’s not true. A’s can have small amounts of chicken and turkey along with plenty of fish options. Tofu (soy) is super beneficial for most A’s.

  152. I completely swear by the blood type diet. I have severe IBS and its the only things, including pills and medication, that relieves my symptoms!

  153. Bloodtypes, Bodytypes, and You by Joseph Christiano is another great book on this subject. I had never heard of Dr.D’Adamo. I got it all from Joseph Christiano.

  154. I am surprised no one seems to be talking about the rh factor of the blood and how that effects the body’s reaction to different nutrients. All blood cells are not the same so I am not sure how so many people arrived at the conclusion that blood type has no/very little effect of how the body absorbes nutrients. Certain foods are treated almost like an allergic reaction by certain blood types and rh factors. It seems most people here recognize that they have to “listen to their body” to see what works week with them in fine tuning a paleo diet. Really all they are doing is observing their body’s reaction to certain foods – what make’s their body react differently to certain foods – blood type and rh factor. That is my thought on all this.

    1. The rh factor isn’t nearly as important as Secretor Status. For the 20% of us that are non secretors it pre-disposes us to more cardio vascular issues, diabetes, dental, auto-immune problems, blood viscosity and stomach acid levels. It also changes the foods we can eat.

  155. PubMed agrees with Dr. D’Adamo and his take on Blood Type history.

    Quoted Text:

    Analysis of a Larger SNP Dataset from the HapMap Project Confirmed That the Modern Human A Allele of the ABO Blood Group Genes Is a Descendant of a Recombinant between B and O Alleles.


    Quoted Text:
    The result indicated that the A allele, possibly once extinct in the human lineage a long time ago, was resurrected by a recombination between B and O alleles less than 300,000 years ago.


  156. I am an AB+ and really wanted to believe this book, but after gaining weight, feeling awful, and having gut issues, all while eating my perfect blood type diet, I had to look at the facts!!! THIS DOES NOT WORK!!! Grains made me sick, the bread he suggests, make me sick and fat and miserable feeling…I went full tilt Paleo when out of desperation I started on the HCG diet, and shots. People it worked because it is Paleo! I did not adhere to the starvation 500 calorie diet they propose, I just cut out all carbs, ate Paleo, and lost 60 lbs. got rid of all my gut issues, and had an “AH HA!” moment. DING DING!!!! I am now feeling great, maintaining my perfect body weight, my skin is no longer dry, inflammation is gone, gut issues evaporated, and have so much more energy.

    If this blood type stuff works, it is because he does propose a pretty good diet of lots of veggies, meats, fruits, and exercise. Just like HCG, it works because it cuts out the carbs. Across the board, diets that work, all pretty much propose the same things, just written a bit different.

  157. I just really enjoyed this and I hope to stumble on many more topics like this. Many thanks for your online contribution.

  158. I am from Scandinavia, blood type A+, and eating according to my blood type is the best thing ever, naturally get slimmer and feel GREAT!
    I started to eat the right way by intuition before I read the book, so that adds trust on the whole thing. Love it.

  159. In the mid 90’s I was diagnosed with celiac disease and also found to be casein intolerant. Soon after being diagnosed I read “Neanderthin” by Ray Audette and Peter D’Adamo’s first book “Eat Right for your Type”. I am a blood type A-. I basically combined the two diets, eating a paleo diet that consisted of turkey, chicken, eggs,and ghee, and blood compatible fruits and veggies. It made sense to me as I have disliked red meat immensely as a child, it just felt “right”. I felt great, life was good! About 6 years ago I decided to widen my diet based on my readings on the paleo/primal movement. I started to decrease my poultry (because it is difficult to get it truly pastured, they are fed grain and soy) and started to eat grass-fed beef, bacon, coconut oil, bone broth, etc. Last year I incorporated Kruse’s epi-paleo diet and started to incorporate a lot of shell fish, fish, and offal. Theoretically speaking, paleo and epi-paleo are brilliant. I wanted these diets to work for me! But they didn’t…to be honest, I never felt worse! Bloated, tired, weight gain. I went back to my type A/paleo diet and never felt better. Last year I read D’Adamo’s new book on the genotype diet. I decided to spend some money and go to his clinic in Wilton CT. and be evaluated. It was a fascinating experience. I learned that I am an Explorer Genotype…I had a “swami” done for my genotype and blood type together, and I’ll be damned but every “avoid” food on my list has always given me problems, such as beef, pork, dairy, coconut, olives…the list is pretty long. I can tolerate poultry and lamb (which is the ONLY red meat I ever liked as a child) and some mild white fish. Unfortunately shell fish and crustaceans are also avoids for me (I so dislike anyway!) but I know they are packed with nutrients. No bacon, no coconut…but yes to ghee and lots of veggies and some fruits. The personality profile of my genotype fits me to a “T”, as well as my exercise tolerances (no cross-fit for me…I have only done hiking/yoga/pilate anyway my whole life), and health and lifestyle preferences as well. His writings on the genotypes are extremely interesting. So, I’m back to my Type A paleo lifestyle and feel so much better. I also started the Leptin Reset again using poultry and find it so much easier this time around using blood type friendly proteins…

  160. and just an addendum to the above, other “super foods” for me are cod, sardines, snails, squab, and ostrich meat all which I really love and have an affinity for, much more than beef or pork…there are about 10 other fish that are considered super foods for me but I haven’t tried them yet! I think that the people that just brush off the blood type diet as nonsense are behaving similar to the people who used to same the same thing about the paleo/primal diet! I think Peter D’Adamo is actually quite brilliant…I use some of his supplements also for my blood and genotype and they are probably the first supplements that I’ve ever used where I actually felt an effect. God, when I think of all of those years that I tried to down the Green Pasture fermented Cod Liver oil (a big “avoid” for me)…ugh, what a waste of time and money.
    It’s sort of a no-brainer for me now in terms of herbs and supplements etc…

  161. Say Mark Sisson, what’s your blood type? Sounds like you’re an O to me. 😉

  162. I’ve been following the blood type diet for quite a while now and I have had huge success. Apart from the obvious weight loss, I am healthier than ever before. Even my allergies are gone. It’s just amazing how your body can react if you eat the right foods. I don’t follow any specific “plan”, I just make sure that I only eat from foods that are neutral and beneficial for my blood type. You can avoid so many health issues that people deem “normal with age” so I cannot imagine why people won’t want to benefit from this 🙂

  163. About five years ago I was diagnosed with gastritis(which means I am painfully gassy in part) and meniers disease (a buildup of fluid in the inner ear)which causes vertigo, and along with vertigo, which lasted 3-5 days during my attacks, I also couldn’t eat anything from the constant vomiting. These two combined really messed up my world. Once I was diagnosed I was told to go on a low sodium diet and to cut out chocolate, caffiene, and meats as much as I could. I admit I am a chocolate freak, and I really love my coffee, SOOOOO i still partake from time to time, BUT meat…the big one. I love my filet, but it doesn’t love me. I cut out salt initially with a vengence and my vertigo came less and less. It wasn’t as hard as I thought it would be but let me tell you EVERYTHING has salt in it, even my drinks, processed of course. Once I got control on the sodium in everything…I noticed that I didn’t want to eat red meat. My stomach would cramp any time that I ate even a little bit, so I slowly began cutting it out and eating fish, chicken, turkey, and beans as a substitute. Now I have completely removed red meat and I don’t remember the last time my gut hurt. I began eating for my blood type about two years ago, A- agrarian, and I feel SOOOO much better. I don’t follow the diet as law, but I try to stick to it as much as I can and want. If I want chocolate I eat it, but not a whole bar, just a bite or two and I am good, it feels good to have control over my food issues.
    I began this journey of excercise and eating right about 12 years ago at 190 lbs. I am a 5’3″ woman with a medium frame and that was TOOOOOOO much. I am now at a comfortable 127 lbs and plan to stay there, following these restrictions may not be exactly suitable for everyone, BUT someone posted a question, why keep eating things that don’t make you happy? My response is I eat things that make me happy and keep my body happy too. I may love to eat a nice rare filet and mashed taters with gravy and a fat ear of corn, but really a piece of cod and a salad makes my day much more productive and feel good for me. SO don’t fuel your hybrid with diesel…

  164. I tried the blood type diet long before I switched to paleo — I did this as an experiment while at an artists’ retreat in a rural, very cold area where I knew I wouldn’t be doing my own cooking or exercising that much, but where the food served was ‘clean’ and where ingredients at the cafeteria meals were clearly marked for those with food allergies, and where there was a salad bar at lunch and dinner daily with oil/vinegar dressing as an option. I more or less ate a modified paleo diet — I’m a blood type O and have tested with my doctor for wheat/dairy/soy sensitivity, so that puts me on the paleo path anyway, the only real change being an edit of my gluten-free carb choices.

    So, long story short, I was at a cold windy writing retreat for 3 weeks and lost 2 lbs — without exercising, and the occasional wine — by following recommendations for Type O. I attribute the success not to the blood type diet recommendations but to this diet’s similarity to paleo. I more or less ate paleo with some non-paleo gluten-free choices (zing bars for breakfast on days I couldn’t have eggs, occasional Lara bars, rice with curry dishes or steamed chicken/broccoli from local chinese place on days I couldn’t have the cafeteria offerings), occasional peanut butter, and sometimes had some paleo choices that could’ve been better replaced with other options (sometimes for snacks I had pumpkin seeds and a few prunes).

    I think this diet, as the article outlines, helped more b/c it advocates clean food for the various blood types. The varying lists of fruits and veggies and meat choices felt a bit random, but you do get all the food groups. Paleo is simpler and more logical to pick up (and to follow, even among non-paleo folks), in my view.

  165. I’m O negative and followed the O blood type off and on for a few years. The biggest thing it highlighted for me was how awful gluten is on my system. But I always did pretty well with some of the softer, non-aged cheeses, and terribly with the few hard ones mentioned as neutrals on the original diet.

    Then the Genotype diet came out. My choices were between the Hunter diet (a classic blood type O diet that heals a sensitive gut) or Explorer (usually Rh negative folks who tend to be sensitive to chemicals and drugs and who tolerate a big more grains and beans and dairy than the classic Hunter/O diet). Given my history of chemical sensitivity and bad reactions to drugs, I started playing around with both lists. I found that when I eat the beneficials and totally avoid the avoids on the Explorer list, I feel amazing.

    Two years ago, I tried a paleo diet. I felt amazing for a few weeks then started getting migraines. I couldn’t figure it out because I was eating more greens and veggies than I ever had in my life. About three months in to hard core paleo, I threw in the towel due to migraines every other day, and back pain and fibro so bad I was crying every other night. Went back to my Explorer diet, and was so much better a week later. I tried paleo again a few months ago, after seeing Chris Kresser talk at a book signing. Asked him why I was getting migraines on paleo. He said it could be histamine or salicylates and to give paleo another go. I tried eliminating the foods that would be causing those symptoms. It didn’t matter. Same deal. The migraines were crippling. Once I was eating brown rice and beans again, on a regular basis, they were gone.

    In hindsight, I know now that I have an MTHFR mutation (which tends to cause chemical sensitivity), but the Explorer diet takes that into account and emphasizes high folate and magnesium rich foods (critical if you have an MTHFR gene). I also know the Explorer diet tends to be lower in histamine and salicylate (but if a food is incredibly beneficial, even if it contains more than other foods, it’s included).

    Dr. D’Adamo’s philosophy is that if you take everything away that makes you sick, you won’t get sicker. But if you add things in that are crucial to your health, you’ll thrive. Such was the case for me with rice and beans. I still love the principles of paleo, but I get too sick on the diet to stick with it. Big huge fan of Dr. D’Adamo!

  166. I began my foray into dietary elimination after reading D’Adamo’s “Eat Right 4 Your Type.” Coming from a background that was solidly entrenched in western medicine, the FDA diet, etc, etc, it wasn’t entirely believable to me. What kept me researching was the word “lectin.” I had some biochem background, but I’d never heard of them, so I kept researching. To this day, I still do, everyday – because there is so much information in the field of lectinology that one person cannot ever retain all of it.

    In this respect, the concept of a blood type diet can change lives: the book – or just the idea that it presents – is an arrow. Some people just take it or leave it. Others start with the statement that is presented and turn that into a list of questions that must be answered, but will (more than likely) lead to more questions. The sum of the acquisition of knowledge is the exponential increase of knowledge. Questions asked now are answers that were too complex for me to ask before my current knowledge base.

  167. I believe that even the best diet systems are never 100%. Some closer than other. I am blood type A and have tried the paleo diet for a few years but have not felt great on it at all. Even though I thing Dr. Dadamo’s historical reasoning should be left out, actually takes away from things, I think on the basis of science, results, and my own experience I love it. It does work for me! No system works perfectly but if it works for you than you need to go with it. I am glad for those who truelly benefit from the primal diet but I can’t do it – have had a lot of physical problems from it. I will definitely myself opt for the bloo type diet.

  168. My mother was type O, my father type A, both Jewish, grandparents came from Eastern Europe. In researching what the Israelites(and probably Christians and Muslims) ate, most of their daily meals consisted of bean or lentil stews scooped up with flat bread made from wheat. They also consumed goat milk, goat cheese, honey and fruit. Meat(lamb &goat) were for special celebrations and I don’t know how often fish was eaten.

    On the Greek island of Ikarias, noted for the longevity and health of its population, their diet is similar to what I described above. They do eat meat once a week and maybe fish is in their, too. They eat sourdough whole grain bread and drink homemade wine. Men between 65 and 100 interviewed by Greek researchers reported that they had satisfactory sexual function. No Viagra or testosterone injections. So, if legumes and grains are so detrimental to our health, why do some people thrive on them? I have severe bipolar illness, migraines and other signs of immune dysregulation. I eat fish, vegetables, fruit, cheese. Recently eliminated gluten but still eat corn. I’m searching for answers and the more I research, the more confused I get.

    1. As for why people your Jewish grandparents and the Ikarians seem to thrive on grains and legumes, and they seem to be so bad for us probably comes down to a variety of things. I found this New York Times article to be fairly well written and balanced. It discusses the various ways that the lifestyle as a whole contributes to the populations long life span. You might want to consider picking up a copy of Death by the Food Pyramid by Denise Minger, she does a pretty good job of explaining why some cultures have thrived eating a diet that relied heavily on grains and legumes – traditional preperation methods have a lot to do with it. This post from 2011 covers that pretty well. Additionally, the number amylase gene (AMY1) copies you have, determines how well you handle starches. The more you have, the less your blood sugar spikes and the quicker it normalizes after a high carbohydrate meal. (Denise covers this in her book as well.) On average, people have 6, but it can vary from 1 to 16.

    2. Hi Mark,
      If your Mother was a Type 0, then you must be the same. Type 0 REALLY needs to give up all wheat, corn and dairy to start feeling better!! I am a Type 0 non-secretor and I have been following Dr. D’Adamo’s diet for 7 years. Trust me, after a long life (I am now 44) of terrible chronic digestive issues, generalized muscle pain, fatigue, headaches, gastritis, etc…finding this diet has literally saved my life!!

      FIRST thing I did was give up wheat and dairy. Within 2 days I was 70% better. I felt like a different person. It is amazing.

      1. Hi, Amy. Since I posted, I went gluten free after a neighbor in Florida who has multiple health issues lent me her copy of ‘Grain Brain’. In a flash, I did a 180 and cut out all grains and dairy, but not fruit. The first change that I noticed was that I was having fewer migraines. Over the course of five weeks, my mood greatly improved. However, when we returned to Maryland in April, my mood and energy crashed big time, though I was still following the no grain/dairy eating.

        For me, Florida is like medicine. I always feel better when I’m there. Back in Maryland, my depression and lethargy are serious. Diet is one part of my health puzzle but it hasn’t proven to be the key to restoring my health. But for certain, it’s a good start.

  169. Amy and other posters, being on Social Security Disability because of severe untreatable bipolar illness, I don’t have the money to buy grass fed beef or liver, free range chicken or eggs. I buy what I can afford. Costco sells two chickens for $10 to 12 dollars, so I buy them and roast them. I buy regular beef [email protected]$2.89 for a pound in Safeway, as well as regular beef. Yes, grains are fed to those animals. Wheat, though, seems to have been significantly problematic. Sure, I could eat just fish, but I like chicken and beef, too. And between wild caught flounder and farm raised shrimp, I drop $30 at Costco.

    Going back to a vegetarian diet(beans and rice) would save me a lot of money but for whatever physical reason, I’ve lost my taste for eating that, though I still do, occasionally. My general health has been declining and I’m in the process of undergoing endocrine testing for thyroid/adrenal/low testosterone issues.

    Animal protein, fish and fruit are what I crave. However, in Florida, I lost 8 pounds(142 to 134). Back in Maryland, gained back most of the weight. As I stated in my previous post, the environment in which I live is as important as the diet I follow. To paraphrase Winston Churchill’s observation about the Soviet Union, “I’m a riddle wrapped in an enigma.”

  170. I tried paleo for a long time, suffered with major digestive issues and bloating and I gained weight.

    I am an A+ and I really find BTD helps me, I also use swami.

    I do agree the common thing with alot of the diets that work are the fact they cut out the crap, removing all processed foods etc.

  171. I was a very low fat vegan (McDougall) when I discovered the ERYT diet. After finding out I was an O non-secretor, I followed the diet and many health issues that were plaguing me got better immediately, especially those related to blood sugar. But there was still something missing. When I discovered that my ancestry was Saami (maternal haplotype) and I added ample fat to my diet, nearly all my issues were solved. I arrived at Paleo through this convoluted path–it fit the way I already was eating. I am so thankful to D’Adamo for giving me a path out of the vegan woods–I think he’s a brilliant man! The only shortcoming is that type “O” is a very broad category; I’m sure there are “O”s that need a lowered fat/cholesterol diet, just not me. I require fat. Without fat in my diet, I get blood sugar problems and gain weight. In D’Adamo’s other book, the Genotype diet, he breaks down the blood types into more specific categories, but I found that I was equivocal in nearly every test, so it didn’t work for me. I still refer to his ERYT books because some Paleo standards just don’t work for me: coconut anything, for instance. So I guess I’m a ERYT/Paleo hybrid. It works! BTW, my husband is an A non-secretor and ERYT works much better for him than Paleo does. It’s all about n=1, isn’t it?

  172. Thank you Mark! This blog really helps! It makes me so confused though… Between, i am curious about your blood type 🙂

  173. Hello,

    I’ve tried the blood type diet (I am A) in the past and I don’t remember it did much difference. I still had IBS before and after that diet.

    I am still experimenting to see what works best for my body. I find the grains give me heartburn and IBS. So far paleo has been working for me. The only problem is constipation and heart palpitations when I eat fatty foods. I also find that on the days when I don’t eat fruits, I don’t have gas either. I am thinking of eating more honey rather than fruits when I’ll get a sweet tooth.

    On the plus side of the blood type diet, I never felt drawn to eating meat. I find that my heart feels better with lighter choices, like vegetarian sources of fats (flaxseed porridge, nuts, butter) and some fish.

    1. Dharia, you should check out Dr. D’Adamo’s SWAMI computer program he has developed over the years since he wrote the blood type diet books. You are probably gluten-sensitive, and you can input that along with all kinds of other things and it will give you what will probably be the perfect diet for you.

      I have found it to be incredibly accurate, as have most people that post on his forums. Much more so than the more general blood type diets, because the SWAMI is specific to you. It tells you which foods are most beneficial, which are neutral, and which foods you really would do well to avoid.

  174. dr laura power has been researching lectins and blood type/body type for 30 years, has anyone consulted her work – everyone seems to say there is no research on lectins or its bunk but thats not what she says. and shes done tons of research. I’m not saying that I like or follow D’Adamo, no. I think he trained under dr Power then came out with his protocol. I just hope we don’t throw out all the evidence based on the wrong author.
    Also, in response to some comment here, if you eat according to your type, maybe at 60, 70 yrs old you will not have your colitis or arthritis or R.A. or Alzeimers…just sayin.

  175. I am an ‘O’ Explorer according to my personalised Swaami. I basically eat paleo but am also following the genotype recommendations as well. Avocado and coconut are avoids for me, foods which I love but make me feel crap. I have tried them so many times because basically I want this all to be a pile of rubbish and for it to be all in my head, but every time I try my forbidden foods, potatoes, most cheese, olives, oranges, coconut, avocado, etc, etc, I feel rubbish!!!!!

    I wish that someone major in the paleo world would just try it and see what they think, rather than just assuming it is rubbish. That would be a great read. I really struggle with being pulled in two directions on this, but I keep on returning because of how I feel. Is it placebo or not?!!!!! I need to do my own n=1 blind study, but it would be a lot of hassle.

  176. I have to testify that I was a fat, sick, lethargic kid and teen. I wasn’t a terrible eater, it was just the wrong foods. In my early 20’s, when I tried the blood type diet (I’m type A+) and ditched the meat (swapped for fish) wheat, dairy and other foods that are contraindicated, I rapidly lost weight, my digestive function normalized, my skin cleared up, I have boundless energy. It may not work for everyone, but boy, did it work for me. I tried paleo a few years ago because there was just so much buzz and hype, along with a friend who is type O. Her health skyrocketed, mine tanked. We still laugh about that.

  177. I am type AB and already ate a diet very similar to what is recommended for me. The biggest change for me was cutting out chicken. I am also not supposed to eat beef. I already knew that beef didn’t agree with me, and had already been eating very little for a number of years already. I have not bought any chicken in months and have only very rarely eaten it when there was no other choice (having dinner at someone else’s house), but noticed that I became sick to my stomach later in the evening and threw up the chicken dinner. People may want to call it quackery or nonsense, but as for me, it clearly is the right diet for me.

  178. I noticed that a lot of the people praising the blood type diets were basically making changes from bad food choices good food choices. So was that the attributing factor or was it the blood type diet? I am on the paleo diet. When I was FORCED to do this I felt FANTASTIC. I noticed that the blood type diet restricted me from most of the foods that I had been leaning on to comply with the paleo diet. This made me frustrated at first, then skeptical. If you are already struggling with a healthy diet, just pay attention to when and if you react to certain foods. Its hard enough to eat healthy! Let alone limit those healthy choices as well! I was glad to see this site supported my thoughts.

  179. Hi,
    Thanks for your article, but check your facts. The selective reaction between lectins and blood type antigens has been known since the 1940s. Independently, in the 1940s, William C. Boyd at Boston University and Karl O. Renkonen at the University of Helsinki, Finland, discovered the human blood type specificity of lectins (hemagglutinins). They found that crude extracts of the lima bean (Phaseolus limensis) agglutinated blood type A red blood cells but not blood type B or O cells, while extracts of the asparagus pea (Lotus tetragonolobus) agglutinated blood type O red blood cells specifically.
    Also, D’Adamo’s work has been independently confirmed by another doctor, Dr. Pierro Mozzi. Also, it is not as simple as cutting processed food and eating more vegetables and fruits. All I really know is that it works for me and that I have seen it work for others. Have also heard from some doctors that it works for their patients. The key bones of contention between blood type O and blood type A are – coffee, carbonated water, bananas, mangos, blackberries, sweet potatoes, red meat, and peanuts. These are healthy for some and unhealthy for others, depending on your blood type. This is not a holy book to me, but it is not a fad diet. If it were, then he would not have sold seven million copies of the book and then updated it twenty years later. He also carried on the research of his father. D’Adamo himself ackowledges that it does not work for everybody. If you read the book reviews on (of “Eat Right 4 Your Type), you find that more than eighty percent are four- or five-star. I suggest you do more research. Also, I agree with you that the theory about the origin of different blood types is uncertain, but this does not contradict the practice that these eating habits, beyond cutting processed food and eating more fruits and vegetables, work for many, many people – for health and longevity and weight loss. My website is under development and to be published in weeks. I review this idea on the website. In brief, vegan tends to be healthy for blood type A, while paleo tends to be healthy for blood type O. This was the original observation of D’Adamo’s father.