The Way to BE

The Links between Your Blood Type and Your Personality, Diet and More Explained

The Japanese have been studying the link between blood type and personality for over 60 years. Find out what your blood type says about your personality and health.

Could blood type provide a key to wellness and even affect our personality? Canadian naturopathic doctor James D'Adamo and his son Peter D'Adamo think so. In Japan extensive research on blood type and personality began more than 60 years ago. Blood type can be a valuable clue for understanding your own uniqueness.

Today, it is even more common to hear the Japanese ask your blood type than it is for Americans to ask your astrological sign.

To most Japanese both biology and genetics have a role in determining personality. Approximately 90% know their blood type and for decades, blood typing has been used by: employers whenassessing job candidates, dating services for potential love matches and even companies for marketing soft drinks and other products.1

I seem to have a special relationship with Japan. I lived there from the ages of 12 to 15. I also studied with Lima Ohsawa, who founded Macrobiotics with her husband, George Ohsawa.

During my years of travel and study in Japan, I had an opportunity to learn first-hand the ways that the Japanese used blood types and it immediately caught my attention -- especially because several years earlier I had also become fascinated with the work of Dr James D'Adamo.

His theory focused on how blood type could indicate the foods and lifestyle choices most compatible for you. One man's food is another man's poison. After meeting Dr James D'Adamo and reading his book, I began to question everyone about their blood type in an attempt to verify if blood type diet indeed provided clues to our individual uniqueness.

Twenty six years later, I am certain it does have merit and is worth our attention. In fact, when I began working with children with autism, I quickly saw that 8 out of 10 of them are blood type "A". An "A" myself, this told me a lot about the little bodies they were in and what their special needs were.

Knowing that blood is the most fundamental nourishment for our bodies, it seems to me that different blood types would react differently to certain substances in food. Please reflect on this theory yourself and see if you don't agree. While there is not a lot of "hard science" to date on blood type, it makes a lot of "common sense" to look further into this theory. Blood carries the nutrients of foods into our cells and clearly not all blood is exactly the same.

While Dr. James D'Adamo's theories were based on patient observation, his son Peter D'Adamo has tried to use a more scientific approach on the activity of lectins (proteins found in food). Peter found that eating the wrong lectins for your blood type could cause weight gain, early aging and immune problems.

I credit much of the blood type information presented in The Body Ecology Diet to both James D'Adamo and Pete D'Adamo's research, but because of my own observations with blood type and my fortunate exposure to the Japanese theory on personality and blood type - and as you will see in more detail in The Body Ecology Diet book -- I do not always agree with these two brilliant and creative men.

Blood Type and Personality

There are four blood types: O, A, AB and B, with blood type A being the most common where so much research on blood types have been focused -- in Japan. In fact, 74% of the Japanese are blood type A. I find it interesting that the Japanese diet very much favors those with blood type A.

"B" type, the second most common blood type, does not do well on soy, or soba (buckwheat) common foods eaten in Japan. Fish is an important protein for B's and the Japanese consume more fish that any country in the world. Lamb, an important protein for B's, is not available there.

Here are some examples of blood type and personality, based on James and Peter D'Adamo's work:

  • Blood Type A - Tend to be cooperative, sensitive, clever, passionate and smart. Often bottling up anxiety in order to get along with others, they may hold in their emotions until they explode. Many are tense, impatient and unable to sleep well. While they are capable of leadership positions, they may not take them because the stress is not good for their tightly wired systems. In Japan many "A"'s are in research. They have roles in discovering more about and refining science, economics, manufacturing, etc. Their research on microflora and other areas of medicine is some of the best and most meticulous in the world. They are perfectionists to say the least. This quality shows up in their perfecting electronics like TV's and also less expensive more efficient cars that were originally created here in the US.

    Blood type A's tend to have more sensitive constitutions. Too much stress weakens their immunity more quickly than other blood types. Low stomach acid is common among blood type A's even from birth, so special care should be taken when eating animal proteins. Using digestive enzymes, like Assist Dairy and Protein, along with consuming fermented foods and drinks is really a must for A's. It is not surprising to me that fermented foods like Miso and Natto play an important role in providing easily digested protein, in the Japanese Diet. They also eat raw fish which is much easier to digest than cooked.

  • Blood Type B - Blood type B individuals tend to be balanced: thoughtful like A's and yet ambitious like O's. They are empathetic, easily understanding others' points of view, yet often hesitating to challenge or confront. Chameleon-like and flexible, they make good friends.

Peter D'Adamo found that While their immunity is strong, they are more prone to slow-growing viral infections like lupus, MS and chronic fatigue.

They may also have problems with hypoglycemia and blood sugar, especially if they eat the wrong foods.

  • Blood Type AB - Tend to be very charming and popular. They don't sweat the small stuff and can be seen as spiritual and even at times a bit "flaky". Only about 2 - 5% of the population are blood type AB. There is never a dull moment in a AB's life, so if you find one for a friend, consider yourself lucky! Youll enjoy some exciting times together!

    Like blood type A's, AB's react to stress poorly. They are stronger and more active than type A's, but need to pay attention to stress levels so that they don't compromise their immunity.

    Sometimes it is difficult to be an AB. AB's don't like to fit in anyone else's "boxes". If they feel too confined, they'll break out of that box and do things their own way. When it comes to food choices and AB must discover when they are more B-like or A-like. For example, dairy foods like milk kefir can be excellent for them or not good at all.

  • Blood Type O - Tend to be loners or leaders and are intuitive, focused, self-reliant and daring. They handle stress better than other blood types and have strong immune systems, a well developed physique and a physically active nature. Blood type O's tend to have sluggish blood flow and feel better with vigorous exercise for about an hour each day.

Obviously many other factors influence your personality. I think you will find like me that these blood type theories are quite fascinating. Do your own subjective research and see if you agree or disagree.

To find out more about blood types, including what foods to eat and avoid and ideal exercise, be sure to read The Body Ecology Diet.

In 1994, I began writing about blood type and diet in the 1st edition of The Body Ecology Diet. When Peter D'Adamo's book, Eat Right For Your Type came out in 1996, we began to get questions on some of the conflicting information in the two books.

Based on our years of working with clients to create a system of health and healing, I feel that the Body Ecology system expands upon Peter's work and goes further toward helping you know and care for your body.

Experiment and Be Your Own Guide

While Body Ecology believes that the blood type theory can provide clues to your diet and health, this is atheory so therefore, still in development. The Body Ecology Diet offers a series of guidelines about your blood type so that you can safely experiment. Hopefully you know your blood type -- if not its worth finding out (via your doctor, for example).

Keeping in mind the Body Ecology Principle of Uniqueness, blood type may be a way to modify Body Ecology guidelines for your own unique situation.

Try it out for yourself and see what you think! We'd love to hear about your experiences.

And also TRY THIS FUN EXPERIMENT -- forward this article to your friends and family and inquire about their blood types and start your own research to discover how valid the above information about personality types may be!

Want more articles like this?

Sign up to receive weekly articles. You'll also receive a 15% off coupon, weekly articles, and tips from Donna and her team.

I'm most interested in:
  • WaffenSS

    I have pure Germanic Aryan blood. Hitler and the Third Reich was very interested in blood and soil.

  • blood type

    TRY blood type personality diet dating

  • Todd K Autman

    I'm O- so not really sure with me.

  • Kevin Broomall

    I am A+ and this article is accurate for me. As for my stomach acid issues, I use organic apple cider vinegar. This home remedy helps balance your stomach pH by neutralizing stomach acid. It's generally accepted as safe to consume a small amount of apple cider vinegar. It should be diluted with water. I like mine with lemon club soda.


    i am Dr Lawson David ,we are in need of a Kidney donor who is in a good health we are ready to offer 600,000 US Dollars for just
    one Kidney.Intrested persons can contact me via:
    whatsapp number :+918973520942
    contact number : +918973520942

  • Anita Gob

    As an A+ I have many of the gut issues mentioned for my type...what do you think about probiotics? OR can you recommend an alternative to taking them?

  • Lynn Hankins Ritchie

    My sister and I are AB+ Personality fits to a T.

  • Mark O'Neill

    Type O is more common than Type A in most of the world. Maybe Japan is different, but the sentence is misleading.

  • Wray Roberson

    I'm AB Negative.

  • Jun Kyo Sha

    i don't care about food at all...but now i know why sometimes i had stomach ache and i always easily stress in many way but i don't know the real reason of my stress..perhaps its true that i'm bottle up my feeling..and when it comes to explode,my rage is very in critical phases that i don't want to meet anyone or despondency struck me..,i'm shy but determined in my doings but when the stress comes,from time to time i'll quit it to avoid from getting any illness like unnecessary fever or low blood pressure...but sometimes i asking myself why i always lack of interest of something? it is relate to my blood type of A+?

  • Mohd Usman

    Nice ....I 'm AB- it is very helpful theory yo discovered yrslf...

  • Sara Bloom

    Blah. I am type A positive but my personality fits with type O.

  • Isha

    Hey my blood type is Q!

  • muloivan

    am a group O+ and indeed i am too much of aloner thou i like it, it makes me feel secure and gives me time to study my surrounding

  • ali mohamed

    I am type AB+ the research done above gives my real picture of personality and diet well explained for myself. I don't like to lie or be lied by anybody. I am spiritual person, I love other people and even in listening to them. I am not idle person, I like working and consulting very much to get a perfect result. I am generous person and pitiful. I don't take things for granted, I am serious person. I hate any kind of corruption. I like to see all people happy, at all times.
    really it's very nice article.

  • Sophia

    I have am A rh- non secretor and I am curious about coconut oil. Everyone say it is so healthy, but being an A I am strongly forbidded to taste it. I have not found any explanation why. I also see that you Donna strongly recommend coconut oil and you being an A too. I would so much like to hear from you in this matter.

  • Bakht Alam khan

    the described all the features fits with me it is all true that u have describe about A+. i know because my blood group is A+.


    i love those who have split personality like me AB-ve


    Im AB-ve and u can check me what im.................!

  • flora

    I am A+ , i m so much sensitive , i face so much anxiety that i can't think or do anything if i start having anxiety , i have gluten allergy , i have allergy from dust , if i drink cold water i start sneezing , if i eat sour thing i start sneezing , i have low blood pressure.
    i am so sensitive sometimes i hate it.
    but i have great skills in art (sketching , painting , digital art, singing , playing instrument) i am good in badminton , tennis!!

  • sara

    thanks for your article.
    it was really intersting and helpfull.
    I had to have an speech in our class and your article was the best sorce that I found.

  • abdale

    My blood type is B+, frankly speaking i am thoughtful, ambitious,easily understanding to others.
    i always like to have a good friends.

    that is all kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk..........................................

  • Hyip

    This article is right on the money. I'm O+ and I feel like a million bucks after a little bit of physical exercise every now and then. Os should also avoid too much gluten/wheat in their diet, and increase protein from lean meats.

  • john makori nyachwaya

    I am type AB+ the research done above gives my real picture of personality and diet well explained for myself. I don't like to lie or be lied by anybody. I am spiritual person, I love other people and even in listening to them. I am not idle person, I like working and consulting very much to get a perfect result. I am generous person and pitiful. I don't take things for granted, I am serious person. I hate any kind of corruption. I like to see all people happy, at all times.

  • Kinokuniya

    Im o + blood type, n im both a leader n a loner! when there are projects half the ppl want to have me with them but usually i go alone. Stress is non existent to me

  • kefale

    I am blood group o positive and the personality scientifically discovered wonders me when it matched with my behavior,it is perfectly expresses me.

  • Vand

    Im B+ type and its perfectly match with my personality
    toughtful, ambitious, empathetic and always think twice before challange or confront others
    maybe because im thinking about other people feeling too much
    I just dont like make people sad or angry

  • samarbijoy Chakraborty


  • nitish

    I am ab+ and I know myself better than u and the others!
    (1) stress comes as o
    (2)stress handling depends upon my daily stuff:if I workout more intensely than react as B otherwise as A.
    (3) the blood group genetics comes with nature of parents not by their blood and yaa it is complex.
    Message to ABs:increase the level of B in your nature by intense physical exercise.

  • Vaughn

    I just found out my blood type is A positive and also have a gluten allergy. The personality trait fits me perfectly. Some of the foods I agree. However, I don't understand if type A's have low stomach acids pineapple juice and grapefruit were suggested, but makes my stomach hurt. But all in all the foods to avoid and eat were mostly on target. Now I know why I'm still breaking out in hives, avoiding the green peppers, black pepper and potatoes.

  • fadli

    am a+ and this description fits me well thanks

  • Andrea

    I am A positive and the A description does not describe me at all. In fact my horoscope usually describes me perfectly, but this couldn't be more off.

  • Ashlyn

    I am not sure what my blog type is, considering that my mom is A and my dad is O, but both personality traits fit me around 80% accurately each. So I'm wondering what I am, because I'm built for athletics (my calf muscles are twice the size of a regular woman's, and I only played sports for 5 years--no fat on them whatsoever) I love physical activity and exterting my body, but I also tend to be lazy and eat high-calorie foods. I'm smart and self-reliant with the adrenaline junky case, and I consider myself a loner but I do enjoy the company of family more than friends.
    However, I'm also shy but I can be loud and obnoxious. I'm artistic but I copy more than I create (my freehand is better than my tracing).
    So, I'm wondering what blood type I am.

  • chukwu di

    This could be true, because i'm b+ and the b type description fits me perfectly and 2 of my friends that are a+ the a description also fit them.

  • Deborah

    I can't wait to get copy of Body Ecology Diet and am posting a relay back to this article on my web site and will share to all my facebook fans! (

    : ~d~

  • Deborah

    I have written a book about perfume and used this blood/personality theory, how they match and fit into a fragrance. Actually tested this during my work with retail store as fragrance sales person. Customers were so amazed about the accuracy that they convinced me to write a book about it. Check it out on my web site: Scent-Sational Searches.

    During my recovery from a serious lung illness my doc from the CDC turned me on to dr. D'Adamo's early book about eating right for your blood type. It helped my regain my health so i know that there is really something to this whole blood identification to many aspects to our lives that are just being studied and figured out!

  • megersa

    it is very nice.related to my blood type the explain note was 99%right.

  • Lauren

    I'm an O type blood and the A type personality description fits me perfectly... Starting to wonder...

  • http://Body Ecology Mary

    Well, some can say its bunk, stupid, or no better than witchcraft.. I'm here to say your wrong.. I'm a diabetic with high blood pressure.. or that is to say I was... I went on the diet for A type blood, in 8 days I went from blood sugar that I couldn't get any lower than 159 to 112 and blood pressure from 160 over 90 to 121 over 81.. now that's just facts.. I'm sold on what it did for me.. That was only the diet no pills no help just good eating according to A blood type...

  • Patty1217

    My Father had type O- blood. My Mom had A+ blood. They are both gone now & I can't ask questions, but I have been told that with my AB+ blood, my Father could not have been my Father???
    I don't understand this. Are there any abnormal types that can cause this. I know I was not adopted, & I know who my parents were, ~ It is a mystery, & I would love some one to give me a positive answer.
    As for me, It does not change my love for my Dad, or my Mom. I am who I am!!
    Just some answer, Please.

  • Tasleeem ALi Mir

    It is really good. I have AB+ blood group and the indications given above are cent percent fitted on me.



  • shawn

    This is akin to astrology. The contradictory and vagueness is outrageous.
    "Blood Type AB - Tend to be very charming and popular. They don't sweat the small stuff... ...AB's react to stress poorly".
    Get your story straight, you fools.

  • Alice K

    I find the matter of this very interesting, on how blood types can show bits of a personality. I am doing my own research on this myself, using other information I can find but sadly I am only limited on the internet for this project. Do you mind if I use your information as well, credit will be given . My type of research is quite small as I am doing this for a 5th grade science project titled "Can blood types tell or effect a human personality", using my friends to observe as well as the internet to compare and contrast the stated information to the observed.

  • Frank

    That is the same with me,an O+, as with Sammy.

  • azmma

    does blood type a+ the same is A in here ????

  • Mike Dammann

    Yes, the rhesus blood group system has more of an impact on personality than the ABO system.


  • Sush

    I am an A type and the personality described above exactly fits....good research work...Would be more good if health risks could also be shared in detail....

  • Yochanan

    I am assuming the commonality of A's and B's discussed referred to in Japan. On a world-scale, O positives outnumber all others by a good margin.

  • sammy

    That is why I become dull if I SHUN EXERCISE for just two days.O+

  • Michelle

    Wow ...Im an A and this description sums up my anxiety riddled body! and probably helps to explain my epilepsy? wonder if there is a link there somewhere?
    thanks for the article, great reading, only wish my mum was still alive, she had lupus. Perhaps a B?

  • nicholas

    i dont kno exactly what i am. id capture all traits so do my parents. its like have dual personalites. some day im the courageous leader and other days im an angel covering himself up from highly active unless i sit drink and watch then im full of understanding.

  • joe

    Come on, lets start a group right now

  • Kass

    Well, that was very interesting... I would like to know if the negatives and the positives are different though.

  • Luna

    Is there a difference between the - or + personalities????

  • Eduardo

    Very nice article.

Community Poll

What Health Topics Are You Most Interested In?

Free Shipping!

Free Shipping on any order over $50

Join Our Community


Information and statements regarding dietary supplements/products have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease. Information on this website is provided for informational purposes only and is a result of years of practice and experience by the author. This information is not intended as a substitute for the advice provided by your physician or other healthcare professional or any information contained on or in any product label or packaging. Do not use the information on this website for diagnosing or treating a health problem or disease, or prescribing medication or other treatment. Always speak with your physician or other healthcare professional before taking any medication or nutritional, herbal, or homeopathic supplement, or using any treatment for a health problem. If you have or suspect that you have a medical problem, contact your healthcare provider promptly. Do not disregard professional medical advice or delay in seeking professional advice because of something you have read on this website.