Does the Blood Type Diet Really Work?

Written by Dr. Steve Chaney on . Posted in Food and Health, Issues

Is Eating Right For Your Blood Type A Sham?

Author: Dr. Stephen Chaney

cb43e76f-6bf7-4e82-8fc1-95005d2c5626Does the Blood Type Diet really work? In 1997 Dr. Peter J. D’Adamo wrote a book about the blood type diet called “Eat Right 4 Your Type”. Dr. D’Adamo claims that people with different blood types process food differently, so their blood type determines the type of diet that is healthiest for them. Specifically, he claims that people with:

  • Blood group O are descended from hunters and should consume high protein diets.
  • Blood group A are descended from farmers and should consume a near vegetarian diet – completely avoiding red meats.
  • Blood group B are descended from nomads. They have the most flexible digestive system and can eat the widest variety of foods – even dairy products, which he does not recommend for any of the other blood types.
  • Blood group AB are an enigma and are somewhere between blood group A and blood group B.

It’s an interesting concept. Dietary recommendations are made for populations as a whole, and there is tremendous genetic variation in populations. Because of that genetic variation, there is no perfect diet for everyone. Every knowledgeable health expert will tell you that.

The question then becomes “How do you know what kind of diet is healthiest for you?”

The blood type diet is a very simple system. Your blood type is easy to determine. Once you know your blood type you know what to eat. There’s no guesswork.

Could it really be so simple? Over 7 million copies of Dr. D’Adamo’s book have been sold. Millions of people believe in this concept. So it is only fitting to ask “What is the evidence?”

An Objective Scientific Analysis of the Blood Type Diet

There is no doubt that blood type is related to some human genetic and physical traits, but the important question is whether blood type is related to the health outcomes of different diets – the central thesis of Dr. D’Adamo’s book. A Belgian group lead by Dr. Emmey De Buch did a systematic search of the scientific literature to answer that very question (L. Cusack et al, Am J. Clin. Nutr. , 98: 99-104, 2013).

They identified 1415 scientific articles that had the phrase “blood type diet” in either the title or abstract. Then they begin the elimination process. They eliminated:

  • Studies done in test tubes, cell culture, or animals. Only human clinical studies were included.
  • Reviews, commentaries, letters or opinions. Those contained no original scientific research.

At this point they were down to just 16 published clinical studies. Then they asked which of those studies were designed to test the central hypothesis of the blood type diet. They asked:

  • Did the study start with human subjects grouped according to blood type?
  • Did the study have an intervention in which the subjects were required to adhere to a particular type of diet?
  • Did the study measure a health outcome of the dietary intervention?

Guess what? Only one study met these criteria. Just one! And it was a fairly weak study involving a totally different blood typing system than the ABO blood groups.

The Bottom Line:

1)     There is no scientific evidence supporting the blood group diet. A lot has been written about the diet, but nobody has actually shown that it works. The Emperor Has No Clothes!

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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Comments (5)

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    Is this a paid subject or did you customize it your self?
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    • Dr. Steve Chaney


      Dear Tiffany,
      Thanks for your comments. I definitely had help setting up the blog. I’m a scientist, not a tech expert.
      Dr. Chaney


  • Nancy Fickas


    You have done a fantastic job clarifying for us so much misleading information this is out in the news and on the web. Kept it coming I love to be able to have a source for accurate information. Nancy


  • 網路行銷公司


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Latest Article

Frozen Shoulder Pain Relief

Posted February 21, 2017 by Dr. Steve Chaney

Frozen Shoulder, Rotator Cuff Pain, No More!

Author: Julie Donnelly, LMT –The Pain Relief Expert

Editor: Dr. Steve Chaney

frozen shoulder pain reliefA frozen shoulder is a mild sounding name for a seriously painful condition that prevents your shoulder and arm from moving. Muscles in your entire shoulder are responsible for frozen shoulder and rotator cuff injuries. Each one needs to be treated for relief, and each impacts the others so it’s important to treat all of them to achieve frozen shoulder pain relief.

Last month I showed you how to do the treatment for the Infraspinatus muscle in the back of your shoulder. This month we’ll talk about two muscles in your chest that prevent your arm from going back.

Muscles that Cause Frozen Shoulder and Rotator Cuff Injuries

The muscles are your Pectoralis Minor and Pectoralis Major which are on the front of your shoulder. If you put your hand on your chest as shown, you are right on top of both muscles.  You can also move your hand down a bit to treat the rest of the two muscles.

frozen shoulder pain relief treatmentThe deeper muscle is your Pectoralis Minor which goes from your ribs up to the top of your shoulder. This muscle pulls your shoulder forward and causes your back to round. When it is in spasm, you have poor posture and can’t bring your shoulder back.

The surface muscle is your Pectoralis Major which goes from your chest bone (sternum) to your upper arm. When this muscle contracts normally, you bring your arm in toward your trunk and/or across the front of your body. If it is in spasm, you can’t bring your arm out away from your body.

You can see how these two muscles will cause frozen shoulder by holding your arm tight to your body.

Since they both move your shoulder and arm, while they aren’t technically rotator cuff muscles, they impact your rotator cuff.  So, these muscles have to be addressed as well for frozen shoulder pain relief.

Frozen Shoulder Pain Relief Treatment and Rotator Cuff Injury Treatment

Place your opposite hand onto your chest as shown.  For example, if you are treating your left shoulder, you will put your right hand on the bottom. Press your fingertips into your chest and place your left hand on top of your right hand.  Press into the muscles with both hands to add strength to the movement.

pain free dvdIf you don’t feel the tender point at first, just move your fingertips around and keep pressing.  When you hit a sore point, you are on top of the spasm. Hold the pressure for 30 seconds and repeat. Do this 2-3 times, and then look for another tender point.

It is most beneficial if you combine this treatment with the treatment for the Infraspinatus that was shown previously.

There are so many shoulder treatments involved in the release of frozen shoulder and rotator cuff injuries that I can’t show all of them. If you suffer from shoulder pain or limited flexibility, I suggest you look at my book Treat Yourself to Pain-Free Living. This book will help you with frozen shoulder pain relief.

Wishing you well,

Julie Donnelly



About The Author

Julie Donnelly is a Deep Muscle Massage Therapist with 20 years of experience specializing in the treatment of chronic joint pain and sports injuries. She has worked extensively with elite athletes and patients who have been unsuccessful at finding relief through the more conventional therapies.

julie donnellyShe has been widely published, both on – and off – line, in magazines, newsletters, and newspapers around the country. She is also often chosen to speak at national conventions, medical schools, and health facilities nationwide.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.