The four blood types
The theory is new, first enunciated by James D’Adamo, an American physician some twenty years ago, and later elaborated by his son, Peter D’Adamo, also a physician. Briefly, but very briefly, the theory states that Type O represents the primitive hunters and gatherers, the most ancient of the four blood types. Type O is distinguished by a good digestive tract, strong immune system, but high stomach acids and low thyroid function. This type is prone to develop stomach ulcers, blood clotting disorders, inflammatory diseases, is often allergic to cereals and dairy products, and tends to put on weight when not exercising enough. Naturally, this is a quick summary, not a detailed description.
Type A represents the second oldest group, the Neolithic farmers and cultivators. This type adapts well to dietary and environmental changes, metabolizes easier the variety of nutrients, but has nevertheless a sensitive digestive tract, vulnerable immune system, and is prone to heart attacks, cancer, anemia, liver and gallbladder disorders. Type A seems to be the principal victim of modern chronic degenerative disorders.
Type B represents the nomads, with a strong immune system, versatile digestion, no natural weaknesses, but prone to youth onset diabetes (Type I), autoimmune disorders, and chronic fatigue syndrome.
Finally, Type AB is enigmatic, and seems to be the most recent blood type. It appears to be the type best adapted for modern conditions, but makes up only 1-3 percent of the total population of the earth. Despite its strengths, this type is prone to some of the diseases of Type A, such as heart disease, cancer and anemia.
The acid test
The theory has been tested by both nutritionists and some physicians with striking results. I have myself put the theory to the test with thousands of my patients, and the results were a remarkable over 90 percent conformity. But I have gone a little further in testing this singular theory.
If Blood Type O represent hunters, then presumably other hunters of the animal kingdom would have the same blood group. Which are the most typical hunters? Naturally, the felines—from the cheetahs and leopards of Africa to our own house pets. We don’t know much about the blood types of African cats, but we do know that in the US domestic cats are 99 percent Type A, and the rest Type B. Cats, cultivators and farmers (!!) and in their overwhelming majority at that (!!!). Surely, this seems ridiculous and shows the absurdity of the theory, right?
Wrong. On the contrary, this seems to confirm the theory, but also to warn against clinging to words, allowing names to dominate research and scientific thought, and thus loose the gist of the matter and miss the wood for the trees.
Lethal energy and controlled fury
Present day hunters like the San of the Kalahari or the Hadja of the Rift Valley, after wounding an animal they have to follow its tracks often for two days or more, before the exhausted animal can no longer resist or get away. But the hunters’ glycogen, the main carbohydrate fuel stored in the liver and the muscles, would hardly last for 24 hours. In fact, a marathon runner can exhaust his glycogen fuel before he finishes his just over two hour’s run.
A diminished thyroid and low metabolism are precisely the conditions, which would allow the hunters to burn fat when their glycogen stores are exhausted. In the case of the San Bushmen, this fat is visibly carried on their oversize buttocks (a condition technically known as steatopygia), by far the best storage place for a dangerous fuel. Blood Type O fits a hunter’s life like a surgeon’s glove.
But is this how cats hunt? Clearly not. Felines virtually kill in seconds, in an outburst of lethal energy and controlled fury. Here low thyroid function and slow metabolism would be a serious disadvantage. That is precisely why cats, though hunters, belong to Type A and not O. But this also why if we stick to names—hunters, farmers, or what have you—we shall not understand very much. We have to go beyond names to the actual functions involved.And this difference in biological and biochemical functions implies a difference in feeding, living, and disease patterns.
A summary of blood group foods
The food regimens for the four blood types may be quickly summarized as follows.
Type O. Basic meat eater. Suitable foods: meat, fish, fruit, and vegetables, but not all. Limit grains and legumes. Careful with wheat, corn, cabbage, cauliflower, mustard greens, and Brussels sprouts. Try instead kelp, kale, spinach and broccoli.
Type A. Typical vegetarian. Other suitable foods: seafood, grains, legumes, fruit. Careful with meat, dairy products, kidney and Lima beans.
Type B. Omnivore. But careful with buckwheat, corn, lentils, peanuts, seeds, sesame and wheat.
Type AB. Moderately mixed eater. Suitable foods: most meat, seafood, dairy products, fruit, grains, legumes, vegetables. Careful with red meat, buckwheat, corn, kidney and Lima beans, seeds.