GreenSmoothieGirl Logo
Lose 10 Pounds in 10 Minutes. Add 10 Years to your life.
Our beautiful template for infinite variety of greens and superfoods in your smoothies—print this and eliminate the need for recipes! Get it now for free!

Should I “eat right for my blood type?”


Robyn Openshaw - Jun 08, 2012 - This Post May Contain Affiliate Links


A recent grad from Institute for Integrative Nutrition applied for the GreenSmoothieGirl Health Coaches certification and said this:

“I’ve studied over 100 nutritional plans, and the 12 Steps to Whole Foods program is the most comprehensive, practical, grounded approach I have found.”

(That’s the goal. I think I’ve studied all those nutrition plans, too. Most have a kernel of truth, or lots of truth, along with, usually, some problems. And many of the diet plans appeal to popular tastes – such as Atkins, South Beach, The Zone, etc. — rather than being supported by evidence.)

One of the more frustrating diet plans, to me, is the blood type diet. The idea is that you have a certain blood type because your ancestors were from a certain place, so they adapted to a specific diet. You are then instructed, based on having O, A, B, or AB blood, to eat according to the prescription. Vegetarian, highly carnivorous, a mix of the two, grains or no grains, etc.

The diet has no real science backing it. Only a very dubious theory. The theory collapses when you consider that every indigenous population of the world has all the blood types: A, B, AB, and O. It’s also highly problematic when you consider how much genetic mixing and nomadism we’ve had in recent centuries. Few people have both parents going back to the same origins.

Peter D’Adamo fathered the first blood typing program (based on the theory of his father James, both naturopaths) that gave rise to a set of nutrition principles. But others have leveraged the same concept, with different recommendations. It’s tempting, financially, to author a new diet, since those books sell well. I know this all too well, since I waged an epic war with my publisher over the name of my bestseller, The Green Smoothies Diet. I hate the word diet because “diets” don’t work. I wanted to teach good principles, towards a sustainable lifestyle, but my publisher said,

“But American love diet books. They fly off the shelves.”

I lost the war and, in so doing, probably gained financially, as my book was instantly a bestseller for my publisher. It wasn’t a hill I was going to die on, because if it gets the same message out, I can “sell out” on the fairly minor point of a title. (Mostly, I just wanted, on principle, to name my own book!) And Ulysses Press was right—Americans do, apparently, want to “go on” yet another diet.

The whole idea of blood typing does call legitimate attention to the fact that we are all different, with different needs. This doesn’t obviate the fact that there are certain classes of foods that are nutritious to just about everyone. Just because you feel weak if you try to eat only plants, after a lifetime of eating animals, doesn’t mean that for you, vegetables are bad food.

It could mean you are transitioning and cleansing, and that is uncomfortable in the short- to mid-term. It could mean that because degenerative gut problems are nearly ubiquitous (everyone who has indulged in the S.A.D. suffering from them to one extent or another), many of us have developed sensitivities to specific foods. Some of those sensitivities are to good foods. This doesn’t mean that food X or Y is necessarily “bad” for you personally—it may mean that you have a problem to rectify so your body can accept and utilize nutrition from that food class.

Some people are reading this article and preparing to scream at me that I’m wrong because they went on the blood type diet and feel much better. I believe that! But not because you’re eating “correctly” for your blood type.

You feel better because the author of the nutrition program eliminates gluten from the type O diet. That will make everyone feel better, as grains have been hybridized and are causing many people problems. And he tells all type A’s to eat vegetarian, which is actually a good diet for most, if not all, people.

(As always, I refuse to take a stand on whether a limited amount of animal protein is good or desirable or at least acceptable—but it’s clear that more plants, and less animals, is across the board, more environmentally sustainable and more health-promoting.)

You feel better because regardless of your blood type, you’re told to eliminate processed foods such as white flour.

D’Adamo’s theory gets really silly when he tells Type A’s to meditate, Type O’s to do aerobics, etc. (Does this mean Type O’s shouldn’t meditate, and Type A’s shouldn’t exercise their hearts?) He delves into stereotyping personality and character based on blood type, too. It’s really nonsense but can “look” true because some true principles are involved.

Many other experts have soundly debunked D’Adamo’s reasoning and recommendations. He claims type O is the oldest blood type, but in fact, A is. This decimates the crux of his theory. Also, agriculture developed in different parts of the world independently, and his theory is based on unilateral development worldwide and positive outcomes for that development, neither of which is fact.

Most of his theory rests on lectins, proteins on the surfaces of foods that can cause cells or molecules to stick together. But a number of doctors object to the hypotheses the D’Adamos make, saying that there is no documentation of the health effects they predict if you eat “wrong” for your blood type, which virtually everyone does, of course. Michael Klaper, M.D. said that the effects he describes would be fatal for millions of people, if D’Adamo were correct in his theory.

The diets D’Adamo advocates for are not particularly harmful or out-of-the-ordinary, and all of them eliminate the worst of the bad in the Standard American Diet. (He isn’t telling any of the blood types to eat Twinkies or Cocoa Puffs. He is just making certain recommendations within whole-foods groups and macronutrients. Most Americans, of course, are eating Twinkies and Cocoa Puffs! Any  involves less processed food is likely to result in health improvement.)

As a culture, we need better critical thinking skills. We have a long love affair with personality testing and typing, horoscopes, and other ways to try to categorize and make sense of our world. But blood-typing theory is flawed on so many levels. I believe that individuals have specific dietary needs that may fall slightly – not massively — outside a prescribed set of guidelines.

Looking to blood type does not provide those answers. As logic might suggest to you, only experimentation and intuition do.

Posted in: 12 Steps To Whole Food, Whole Food

15 thoughts on “Should I “eat right for my blood type?””

Leave a Comment
  1. Thanks Robyn. It’s honestly been too much – considering my daughter is only 23 years old and Nathi fought so hard to live! Those silly doctors argued with us over his status – was it this or that – I didn’t care and we proved them wrong. We miss him so much every day. I guess at least we can see his beautiful face in clips and hear his beautiful voice but it should never have happened. I was getting a little complacent in my fight for the truth but after his death I feel him behind me all the time saying “Go Mum! Wena, you have to tell the truth so we stop dying from medical error!” It’s never going to make up for the loss but he was a freedom fighter as a child in apartheid-run South Africa – how could I not keep fighting in his memory? If you want a blessing today, take a look on youtube under Soweto Gospel Choir – Amazing Grace – Nathi is the first soloist with dreadlocks. Still so painful for us to watch but I know he is still blessing millions. Thankyou also for fighting to share the truth.

  2. Anonymous says:

    Let me begin by saying I am not here to discount anyone or their belief in their own road to personal health. Kudos to you. It certainly is a challenge to discover and then navigate that road in a society that rather advertise and promote harmful, artificial foods and medicines instead of recognizing, honoring and educating its people about the true medicine-Hippocrates’s medicine.

    Amen Melissa and Elinore. Thank you for your responses. You are right and there are some inaccurate statements and generalities made about Dr. D’Adamo, his work and ERYT in Robin’s entry above. It makes me wonder if it is 100% Robin’s words, because all of it does not sound like something she would say or the way she might choose to say it. Please don’t misunderstand my concerns. It all just doesn’t sound like Robin to me.

    Those of us more familiar with ERYT and living it every day are probably more committed to staying abreast of everything ERYT and therefore inaccuracies are obvious to us. My concern is that others, trusting and believing in Robin’s opinion when reading those statements, may form an inaccurate opinion of ERYT.

    Robin, I respect you and thank you for your years of hard work in this very important field of which our nation is facing such a crisis, and for having an impact on all who choose to embrace what you are sharing. I have followed you for more than two years and have learned from you in my journey to better health. I applaud and support your efforts to soldier on.

    In fact, last Saturday, June 9, 2012 I enjoyed bringing a co-worker and my husband, to your class in Evanston, IL to help them learn from you as well. Another co-worker was suppose to join us also, but her sitter fell through at the last moment. We are all very interested in how to get the most benefit from raw vegetables in our lives as we can. They are A’s. I am an O

    My husband and I have been following ERYT, approximately 95+% most of the past two and three years, respectively. My co-worker has been dabbling in the ERYT, not fully committed, but is now returning to it because of her past successful results and lack thereof without adhering to it. She, as many others have at work and in other areas of my life, came to me to find out what I had done that made such a difference in my appearance and stamina, however her interest was in better health and NOT weight loss as a priority. Interesting, I thought.. That’s when the conversation began with her about my journey to find answers for what had been ailing me for years

    My quest was not to lose weight. That was one of the unexpected results. I was quite happy with my curvy hour-glass 5′ 10 ‘ size 12 frame. I had always been an athlete/physically active and tried fine tuning my diet and exercise program to get into bikini shape for vacation several times. It never got me quite there. I later learned the problem was digestive issues. More than I knew, because I discovered that what I thought felt normal digestively was not normal at all. Symptoms I didn’t even know were related all began to tell a story.

    For years I experienced symptoms that no one would give much attention to or have any answers for. Doctors didn’t have answers. My chiropractor tried to some extent, but I was still doing all the research and legwork and all that came up short. The nurses in my family had no clue. Even after sharing some of my own research with all of them I received blank looks, empty answers and little to no support. Obviously, it was all going to be up to me.

    So the research began Boy do I love to research. I read and read and read. Anything I could get my hands on that talked about naturally healing digestive issues was on my radar, on my lap, my coffee table or nightstand, in my book bag and on my Kindle. It was only after coming across information on candida albicans overgrowth did things start to click and then I began to make some progress. Yeast overgrowth is my problem! Now I had to get to the cause and the cure. But, I still knew nothing of ERYT.

    For a year and a half I put most of the practices I had read to improve my yeast imbalance into play. Of course I removed the obvious: Wheat, white potatoes, dairy, corn, sugar, sweeteners, diet soda, anything else that would convert to sugar as well as fermented foods and anything related to or prone to mold. These were mostly nutrition changes, as well as adding some nutritional supplements. I removed what feeds the yeast and added more raw vegetable-only salads to my diet. I still ate chicken, turkey and some beef.

    I went from 173 to 145. I hadn’t weighed that since college. My size shrunk like crazy. Went from a size 12 to a 4/6. I had never been that small and I hadn’t been smaller than a size 12 since before my growth spurt in seventh grade. I lost the pear shape all the women on my mom’s side of the family were known for and thought was my genetic make-up and destiny. Never had a flat stomach–ever! Now I had one.

    As I hovered around 140 and started to lose even more weight, all those negative comments people made to me along the way made me begin to doubt myself and what I was doing. Some thought I wasn’t even eating. Are you kidding me? I was eating more food and more often than ever before—just different stuff. My hip bones were back and my saddlebags were gone. Even the cellulite was vanishing.

    But I didn’t have a scientific, biological, chemical or whatever-it-took-to-convince-people-I-was-on-the-right-path explanation. How do you convince the laymen when even many doctors don’t believe or know that there is such a thing as a candida overgrowth problem? I was beginning to panic at what I was seeing on the scale because I hadn’t seen it since high school and I certainly had never been even close to a size 4 in my life and I didn’t have a simple explanation…until

    …it happened. On one of my many Saturday morning trips to Borders I found Dr. D’Adamo’s ERYT and LRYT books. I couldn’t take my eyes off the pages. EVERYTHING made sense with what I had been already doing these past months! This is why the candida overgrowth plan I had been practicing worked–the food I eliminated to stop feeding the yeast are the very foods that make type O’s sick. Here was the explanation I had been longing for! I had been doing (and not doing) what this plan talked about almost exactly for 20 months!

    I know. During this whole time you’re thinking, “what about your husband?” Maybe many of you have supportive husbands. Some of you may not. I’m blessed enough to have a husband who usual jumps on whatever bandwagon I decide I want to drive. (At least that’s how I see it, lol.)

    Yes, he tried to eat like me in the beginning (before ERYT) and lost about 5 lbs. He wasn’t overweight really, and had always been thinner. But, he did have that over 40 stomach that extends from the chest to below the belt–and that’s without being a drinker. There was the extra width to his face and a roll around his jaw line circling around to form a double chin along with a fairly good-sized set of love handles. Nothing else would have led you to believe that this man I have now known for twenty-four years has had borderline high blood pressure the entire time I have known him.

    Although he ate like me for the most part, he didn’t see the results I did. We didn’t know why. He didn’t have the candida symptoms I had. We weren’t “treating” him for candida overgrowth, but he saw my results with my weight and heard me 24/7 talk about all the differences it was making for me physically that he wanted to experience some of that too. Plus, he was so excited that my results had given my involvement in living new life! I was enjoying living again!

    So after I read LRYT, my husband just knew he had to find out his blood type for sure. He always said he just knew he had to be an O like me, but after his lackluster results with his changes, compared to me, he knew something had to be different. Once we read the more detailed description of each blood type’s beneficial and avoid foods, health-prone risks and stress/exercise suggestions, it was easy for me to see that he was more likely an A. Soon after he gave blood at our church’s blood drive and two weeks later called me at work to say his donor card arrived and in fact he is type A!

    Two days later, we sailed away on a last minute cruise we booked two weeks earlier that was entirely about relaxation, the spa and eating healthy food in their healthy restaurant exclusively for AquaSpa class passengers(Celebrity Cruises Solstice Class of ships AquaSpa cabin class-we cannot say enough about that experience!) My husband–who is still learning how to relax, took the LRYT book to the chaise lounge by the pool and began his investigation to unlock the mystery behind what it would take to tweak his diet to start his journey to heal his health. He spent the entire cruise exploring each opportunity to work toward that important goal. That was a miracle within itself!

    A few short weeks later, after applying the LRYT plan, not only did my husband lose most of his paunch and love handles, his blood pressure is now at a consistently healthy level-one I have never seen as long as I have known him. Meds did not put it where it needed to be, but diet did. And remember this is after “tweaking” his his already healthy diet to be compatible with type A. Now he has personally experienced the effects of applying ERYT/LRYT to his life and almost everyday tells a story about who he has shared ERYT with.

    As I approach my three-year anniversary and my fifty-first birthday, and my husband approaches his two-year anniversary and forty-ninth birthday, I am proud and blessed to say that we both continue to have success with our health with ERYT.

    I could talk forever about what a difference it has made in my life. Do I have moments of struggle and weakness. Absolutely! But ERYT is how I live now and each time I veer off the path, even for a brief moment, my body responds with the reminder/confirmation as to why I need to stay on my road to health that has brought me such fabulous results and given me back my life! Ahhh…now that’s another story…

    Based on what is written above your first reaction may be that I lost weight/felt better because I eliminated most grains. Right? Well, I’ve done that before and I didn’t get those results.

    Then you might say it was the salads. I say, yes they have a lot to do with my success, but they were already in my diet. I just made it a consistent and more frequent priority on my menu. ( I must mention, however, that the easy answer I give people when they ask me what I’ve done and what the key is, is that “raw vegetables are a miracle food.” If that gets their interest, then I tell them more. But it always leads to talking about their blood type and I can always guess what it is, if they know it, when they give me enough info about their issues, how they handle their stress, and yes Robin, even what form of exercise they prefer to relieve that stress.)

    It wasn’t ERYT alone that defined what was happening physically for me, but it began the discovery of more pieces of this crazy puzzle I’ve been trying to put together and each piece along the way verifies and validates what I’ve been doing with ERYT.

    I apologize for the length of this response, but when you are passionate about what you believe in and know that passion has the potential to help and be a blessing to others, it’s difficult to hold back.

    Most importantly, each of our paths to health is unique and personal. Much joy can be found in traveling that path, discovering and learning all we can along the way to enrich, enhance and improve that quest for the most healthy and happy life possible. May we continue to share with each other all that is available to us to make that happen.

    I wish you all the best of health and the happiest of times for you and all you love.

    1. Robyn Openshaw says:

      Amy, congrats on such spectacular results! Very exciting!

      “….I removed the obvious: Wheat, white potatoes, dairy, corn, sugar, sweeteners, diet soda, anything else that would convert to sugar as well as fermented foods and anything related to or prone to mold….I removed what feeds the yeast and added more raw vegetable-only salads to my diet.”

      Anyone who does these things, which is essentially kicking the S.A.D. to the curb, will experience the profound changes you did.

      It’s fun to type people. The exercise part is all wrong for me, based on my blood type, BTW. But what do you do about people in the same family (all close blood relatives) who have four blood types, as mentioned by one reader posting here yesterday? My point is, of course there’s a massive connection and loyalty to a program when you’ve had such good success. Those are the dietary principles that starve out candida in half a dozen books I own. But I don’t want people to believe that because they’re an O blood type, that the risks documented well by Campbell and the Oxford-Cornell team in the biggest nutrition study in history, don’t apply to them, to big meat eaters. Fact is, most animal products in America today are full of steroids, antibiotics, pus, and disease. If you’re going to eat them in large quantities like D’Adamo tells you to do, I hope you’re buying organic, free range.

      When we have the financial catastrophes we are headed for in our economy, government support for meat will eventually fall out. It’s unsustainable. At that time, meat products will cost $20/lb with subsidies removed. That’s a minimum of what it actually COSTS to produce meat (since a pound requires 20 lbs. of plant matter, and 1,000 gallons of water). So it would be wise for all of us to learn to eat lower on the food chain.

  3. Anonymous says:

    “And he tells all type A’s to eat vegetarian, which is actually a good diet for most, if not all, people.”

    A bit of stretch, this above statement is. it’s simply not true that a vegetarian diet is good for most people. Not when most societies are not historically vegetarian, and have always had some form of animal protein or seafood. After resisting eating meat for a while, I feel so much better now that I am back on it. And I know many other people in the same situation.

    I went on a green smoothie craze for about two years and it rewarded me with crazy blood sugar levels and sensitive teeth. And I lost weight which I did not need to lose. It did help my husband, who needed to lose weight.

    One thing you are definitely right about is that any diet that takes you off the SAD path will improve the health of most people. So this does not make the Green Smoothie or vegetarian or vegan diets superior to others.

    Keep up the good fight against the SAD, but really, let us not waste energy on other diets that are already trying to help people turn their backs on the SAD. For every person whom the Blood Type diet did not work for, you will find another for whom the Green Smoothie Diet also did not work for whatever reason.

    1. Robyn Openshaw says:

      MarsHill, yes—but a diet high in meat is well documented (please read the China Study) to massively increase your risk of cancer. Also heart disease and autoimmune diseases. My major issue with Blood Typing is that it rubber stamps a disease-risk diet (for O’s). I am not a vegetarian, either (although I eat zero cow or pig)–but that doesn’t mean eating a LOT of meat is good for anybody.

      There is no “green smoothie diet.” That was just the name of a book I was forced into. There is, however, a whole foods diet, and although within it, there needs to be individual variation based on individual needs, it does work for everyone. Because it’s what EVERYONE ate before processed food was rolled out to the masses by American corporations 100+ years ago.

      There’s no reason for a green smoothie craze to do anything but HELP blood sugar levels, if they are true green smoothies. Greens are not only our most nutrient dense foods, but they control and regulate blood sugar too. If they’re fruit smoothies, possibly with a concentrated sweetener added, with a bit of greens tossed in, you may have yourself a problem.

  4. Anonymous says:

    Actually when I first heard of this book I was very skeptical. I had identified foods that did not agree with my system – all gluten, pork products, cantaloupe were a few. When I read this book these were all identified as ‘avoid’ for blood type O.

    Now there are foods on the list that I have no problem with of course. This book, together with a sensible non-processed food diet is a great starting point. Find the foods that your body doesn’t like and the one’s that your body likes and go from there.

    I think the biggest problem is that too many people don’t correlate the way the feel to the foods they ate say in the last 24 hours. They figure I ate it, an hour later I am fine it can’t be a factor.

  5. Anonymous says:

    My parents have been mainly eating the type O diet recommendations for 20 year or so (whenever the book was first published). Plus vit and min supplements.

    And they are walking adverts for it. Their eyes are clear, they stand upright, they have good teeth, nails and hair. Their skin is firm and glowing. The worst signs of age are joint problems, in my mother from a lifetime of having hyper-mobile joints, and in my father from old car accident injuries. Neither have more than very mild arthritis. I know of no other people their age who look anywhere near so healthy, or who have such active minds and varied interests.

    By the same age, my four grandparents and three surviving great-aunts ALL had one or more of; serious heart disease, emphysema, crippling arthritis, horrendous circulation problems, failing eyesight, narrow mindsets and (probably) undiagnosed diabetes. They ate the old style English diet of meat, two veg, potato and pud.

    Is blood typing ‘the perfect’ way of eating? Probably not.

    Is it a VERY good way of eating? Hell yes.

    It is also a great deal easier to do in a social setting than raw, vegan organic (which MAY be ‘the perfect’ diet!

    1. Robyn Openshaw says:

      Not sure 100% raw is easy, but yes, of course people are more healthy with a diet that bans processed food—but arthritis is unnecessary and caused by highly acidic animal proteins. My problem is that eating a high-meat diet (as in the “O” recommendations by Blood Type diet) is high disease risk. Please read the China Study and weight that in the balance with the blood typing which has been thoroughly and compellingly debunked by a close examination of it.

      And please, let’s ask ourselves, how valid can it be when there is every blood type in every culture—and often several blood types in ONE FAMILY who all have the same ancestry, as is pointed out by a respondent to this very blog post.

  6. There are four blood types among human beings. However, if we were to judge what we ate based on blood types, this should be true for all animals as well. Dogs have 4 different blood types, cats have 11 and cows have 800! By this reasoning, cows should have the most diverse diet of all compared to humans, cats and dogs. Yet, cows all eat the same grasses and a vegetation-based diet. Although each person is unique, we can all benefit from eating a predominant plant-based diet. Our bodies need fuel to run and food is our fuel.

    1. Robyn Openshaw says:

      Alina….exactly. Good stuff.

  7. Faye says:

    I had a food sensitivity test and a lot of it matched with the eat right for your blood type, it was pretty close.

    1. anonymous says:

      I had exactly the same experience! The ones that the naturopath and the allergist told me were sensitivities matched exactly to the blood type avoid list.

  8. anonymous says:

    I think in your effort to sell your own concept you did not research this article well enough.
    The Blood Type diet is based on science…
    I have been following it for years and it has made me feel better and have more energy.
    It is not for weight loss, but to avoid the issues and problems caused by eating items that your body will find toxic.

    Interestingly enough, the sensitivity testing I had done at an allergist AND a naturopath BOTH found sensitivities to the foods that the Blood type diet was indicating were toxic.

    THAT is something I cannot ignore.

  9. Joann says:

    I find it a bit disheartening to find the same old disparaging information repeated on many sites regarding Dr Adamo’s work based solely on (maybe) perusal of his 20 year old book- ERFYT. Since that time Dr. DAdamo has continued to expand his research. He has written several other books and a 20th anniversary edition of ERFYT will be out in Jan 2017 which will include new information regarding diet modifications based on his 20 years of research. In his latest newsletter, which I receive, he discusses in an excerpt from his new book, the connection between blood type and the Microbiome- different blood types have different types of gut bacteria. Some are beneficial to specific blood types and not so helpful to other blood types.

    Dr D’Adamo has a website and has helped formulate many 4 your Type supplements which are sold on many online health food sites

    I have been on the 4 Your Type diet for several months and with the helpful guidance of customer service I have taken some of his supplements for a while until I no longer needed them. I’m a Type A who has been much more comfortable as a vegetarian for years and this confirmed it for me. I had to rethink the benefits of soy, which I had avoided thinking it was “bad” for me. When I researched it more, I realized I had bought lots of misinformation, I only use organic, non-GMO soy. Dr D’Adamo suggests 80-20. Eaf Beneficial foods 80% of the time. So this diet is not meant to be rigid. I have experienced vast improvement in my gastrointestinal tract.

    Dr D’Adamo is considered a world expert in glycobiology, principally the ABO (ABH) blood groups and the secretor (FUT2) polymorphisms. He is currently a Distinguished Professor of Clinical Sciences at the University of Bridgeport Connecticut.

    I don’t believe there is a one size fits all diet and this one may be worth another look for some. i have read several of Dr D’Adamo’s articles and they are fascinaring. I think he is way ahead of his time and medicine is now catching up a bit.

    1. Robyn says:

      Hi Joann, I don’t intend to disparage anyone personally, but rather to point out that a number of experts have completely debunked D’Adamo’s theory that we should eat according to his types, based exclusively on our blood type. Certainly biodiversity is real, and some do well with meat, and some don’t (I’m with you, prefer vegetarian), but his diet gets people off the S.A.D. but is fundamentally, scientifically deeply flawed.

Leave a Reply

Your email address will not be published.