Blood as blueprint
Most people but also many health professionals know the four blood groups or types from the viewpoint of blood transfusions. In other words, the fact that Type O may be administered to any other group, while types A, B and AB must be confined to their own. But blood types seem to have some other important properties. They appear to determine certain physiological and biochemical functions, and to a point, the pattern of our diseases and our body's nutritional preferences.
In fact, our blood type is a blueprint to our body chemistry; a reliable guide to our nutritional absorption, and a cipher code to both the diseases we are prone to, and the foods which can best prevent them. The modern theoretical basis of blood groups first made the headlines about 20 years ago, but as usual when new ideas appear which do not quite fit existing modes, it was given short shrift by the medical establishment .
The theory seems new, but it appears to work remarkably well. Perhaps because it has very ancient roots. The ancient Greeks knew nothing about blood types, since they could not possibly have distinguished the different antigens in the blood, which are responsible for its classification. Yet in the 5th century BC, the Greek physician Hippocrates but also his successors, divided humans into four main types according to the four cardinal humors (blood, phlegm, black bile, choler or yellow bile), the relative proportions of which gave the human types known as sanguine, phlegmatic, melancholic, and choleric and prescribed different diets for each type. We still use their system when we speak of a "melancholic type," since what we are saying is a "black-bile type."
Blood will tell
The modern theory of blood groups says that type O represents the primitive hunters, in other words, it is the most ancient of the four types of the ABO system. Type O is distinguished by high acid stomach secretions. The reason is that the hunter's stomach must break down a lot more animal proteins to their constituent amino acids. Type O is also prone to low thyroid function if not outright hypothyroidism. This has to do with the requirements of primitive hunting (see below). It is not surprising therefore if this blood type has often peptic ulcers, weight problems if not active enough, allergies to cereals and dairy products as new foods for them, colitis because of lack of vitamin K, and other low thyroid related disorders.
Type A represents the second oldest group, the cultivators, the farmers, the pastoralists. They are distinguished by low stomach acids, as their chief diet consisted of cereals and other plant foods, digested mainly in the intestines through enzymatic processes, not in the stomach. Naturally, eating a diet of mixed meals they have digestive problems, gastritis, flatulence, bloating, burping, etc. They are also prone to diabetes. This is because the pancreas was irritated by the new human foods like cereals and dairy products, and resulted in a pancreatic weakness conducive to diabetes. Type A is also prone to cancer and other degenerative diseases. New foods like cereals weakened the immune system. From animal proteins humans can readily get all the amino acids they need. To do the same from plant proteins, we need to know which amino acid is missing from each plant food. But this is relatively recent knowledge; it didn't exist before. The result is that a weakened immune system cannot perform its function well, leaving a person exposed to cancer and other chronic degenerative diseases.
Types B and AB have other predispositions and complications. Being newer blood groups does not guarantee that they have already readjusted to modern realities. On the contrary, they seem beset by all sorts of problems, presumably because they have not yet adjusted to the new nutritional and other realities. These blood groups are particularly prone to health problems, when exposed to lifestyles which are not their own.
The acid test
However, it is customary for us to examine theories and hypotheses, and not take them for granted. If blood group O represents hunters, then presumably other hunters must have the same blood type. Which are the quintessential hunters of the animal kingdom? Naturally, the felines--from the cheetahs and leopards of Africa, to our own house cats. Strangely, however, blood type O is unknown among cats. In the US where there are some relevant studies, 99% of cats are Type A and the rest Type B. Cats cultivators and farmers, and in their overwhelming majority at that!! Surely this is utterly ridiculous, and shows the absurdity of the theory, right?
Wrong. On the contrary, it seems to confirm the necessity for different blood groups, their significance in the life of the species, but it also warns against clinging to words, allowing names to dominate scientific thought, and thus loose the gist of the matter and miss the wood for the trees.
Present primitive hunters like the Bushmen (San) of the Kalahari Desert and the Hadja of the Rift Valley in western Tanzania, when they wound a food animal, they are obliged to follow its tracks often for two days or more, before the exhausted animal can no longer resist or get away. But the hunter's glycogen, the principal carbohydrate fuel of the human organism stored in the liver and the muscles, could barely last for 24 hours. A diminished thyroid function and low metabolism are precisely the conditions, which would allow the hunters to burn fat when their glycogen stores are exhausted. The Bushmen carry this fat mainly on their buttocks, the least harmful fat depot, and it is known by the scientific name of steatopygia. Blood-Type O meets the requirements of primitive hunting and fits a hunter's life like a surgeon' glove.
But is this how cats hunt? Of course not. Felines virtually kill in seconds, in a virtual outburst of energy and lethal fury. Here, slow thyroid function and low metabolism would be a serious disadvantage. That is why cats, though hunters, belong to blood group A and not O. But this also clearly shows that if we stick to names--hunters, farmers, or what have you--we will not understand much. We have to go beyond words, to the actual functions hidden behind them in each particular case, to understand the underlying realities of nature.
Only blood groups are far more complex than that. The blood types of primates do not fall into any simple scheme. Be that as it may, research into human blood types has shown that there is a definite relationship between blood type and a predisposition to certain specific disorders, but also to the foods that can prevent and cure them, as the ancient Greeks had already discovered by the 5th century B.C.
1. Peter D'Adamo 1996 . Eat Right For Your Type. New York