"Eat Right 4 Your Type"
Blood Type Diet
from Deena's Nutritional Guidelines Booklet
The concept of "Eating Right For Your Type" is based on Peter D'Adamo's research claiming that people fare better (including with weight management) when tailoring their diet to their specific blood types. He advises:
Type A types should basically stick to fruits and vegetables (high carbs lowfat). They have thicker blood than other blood types, a sensitive immune system, and should not consume dairy products, animal fats and meats. They are at a heightened risk for cardiovascular disease, diabetes and cancer.
Type B types should consume a balanced diet (fruits and vegetables, grains, fish, dairy, meat, but avoid chicken). They have the best chance of bypassing or overcoming everyday types of diseases, including heart disease and cancer.
Type AB types should consume a mostly vegetarian diet, and only on rare occasions some fish, meat (no chicken), and dairy.
Type O types should basically stick to a high protein diet (including red meat), low carbs, and enriched with fruits and vegetables. They should limit the intake of wheat germ, whole wheat products, corn, and avoid dairy products and most nuts.
Type O types are commonly affected with hypothyroidism, high stomach acid (leading to ulcers), and thinner blood with greater resistance to blood clotting.
Of course there are far more than the ABO group, and apparently results on these may be forthcoming in the future. Being a naturopath, he uses Iris diagnosis, Muscle testing and Pulse diagnosis (not the Western or Oriental type) to complement his assessment of a patient's health.
To support his theories, P. D'Adamo has made some pretty bold and scientific-sounding assertions. These include a hypothesis on lectins, where he claims that they can result in the agglutination of blood cells in an individual with the wrong blood type, and which in turn may create serious liver or kidney problems, as visible under a microscope (lectins are sugar-containing proteins found on the surface of some foods that may cause various molecules and some types of cells to stick together).
He theorizes further that elevated urine indican levels - prevalent in many gastrointestinal diseases such as celiac disease, diverticulitis, pancreatic insufficiency, inflammatory bowel diseases and others - can also be attributed to specific blood types affecting the interactions of foods with intestinal bacteria, and creating polyamine abnormalities.
In addition, different blood types - according to P. D'Adamo - affect the body's secretory performance in respect to digestive juices, whereby a blood type O for instance is capable of producing higher than average stomach acid levels, which could lead to a greater incidence of gastric ulcers.
Although none of his theories have been substantiated or supported by the scientific community, this alone should not necessarily be a reason to dismiss his claims of a blood type / disease association. The evolution of medical science itself is paved with scientistic blunders and practices where "Scientific Therapies" of the past have in the meantime joined the ranks of "Quack Therapies," while some of the "Snake Oils" of today may be the newest "Scientific Breakthroughs" of tomorrow.
When applying an "Evidence-Based" approach to medicine, how do various blood types compare to various medical conditions and various chemical profiles -- or do they at all? If they did, and formulating diets or supplements around blood types were indeed a valid proposition, then blood types should a) coincide with specific medical disorders, and b) match the chemical and nutritional profiles of patients - similar to the premises proposed in the Metabolic Typing of patients, where diets are adjusted to someone's genetic and biochemical make-up.
Ever since first hearing about the "Eat-Right-For-Your-Type" proposition, I started to compare patients' blood types to their chemistry and their medical disorders -- looking for trends or a pattern. In other words, high blood pressure, high blood sugar, or high stomach acid types should logically have different blood types according to this "blood type theory" compared to low blood pressure, low blood sugar, or low stomach acid types. At the same time, people with a life-long tendency for weight gain, weight loss, nearsightedness, farsightedness... etc, and many other "hyper" versus "hypo" conditions should equally share similar blood types. Unfortunately, I was not able to come up with any match whatsoever - just like eye color and hair color are no indication of a person's present or future medical risks.
Of course some people I have talked to mentioned that ever since following the 'eat for your blood type' recommendations, they had lost some weight or otherwise felt better. However, when asked about any specific changes made, they invariably consisted of life style changes that are universally considered to be beneficial, regardless of someone's blood type (eating a balanced diet and cutting out junk foods). The decision to increase certain foods, or eliminate food sources that someone has an intolerance or allergy to (wheat, dairy, eggs, meat, nuts, seafood, certain fruits or vegetables...) can definitely have a significant impact on someone's health, but the need to do so does not depend on being born with a particular blood type.
The claim that individuals with certain blood types suffer from specific medical problems (i.e. "Type O types are commonly affected with hypothyroidism, high stomach acid [leading to ulcers], and thinner blood...") are absolutely absurd, as any medical professional who treats these conditions and has the resources to investigate those claims can attest to.
But let's assume that at birth, Peter D'Adamo's hypothesis were indeed valid --- then the effects of diseases, medications, pathogens, trauma, recessive genes... would then quickly negate any possible consensus between blood types, nutritional requirements, or ending up with specific medical problems.
For example: Considering a Type O individual, who has been enjoying and tolerating a high protein (red meat) diet all his life, and then he eats E.Coli-contaminated hamburger, ending up with kidney damage. Obviously, his blood type is still Type O, however unless he changes more to a "Type A Diet" now (more fruits, oxalate-free vegetables, low purine diet), he will either soon encounter his first gout attack , or worse, he'll be soon on dialysis.