Researchers have known for some time that two major diseases of the gastrointestinal tract were associated with blood type. Duodenal and gastric ulcers, which are associated with high acid levels, are more common in type O individuals, and gastritis, a condition associated with low acid levels is more common in those with type A blood. Taking these observations further, Doctors James and Peter D’Adamo have now concluded that your blood type is one of the major determinants of what disease conditions will affect you. Eating inappropriately for your blood type may also be implicated if you are suffering from fat that is hard to shift despite all your best efforts to increase the amount of energy you burn up and decrease the number of calories you consume.
The explanation for both situations lies with protein molecules in foods, called lectins. These molecules are potent biological signals or "information" molecules and as such, they deliver messages to cells and are able to alter the body’s metabolism. They also mimic the blood group antigens, so depending on whether the lectin has a type A or a type B effect, agglutination (i.e., cell clumping) will occur. Thus, some foods that contain specific lectins may trigger a process similar to rejection in some blood types but not in others. Agglutination is associated with the destruction of tissue and the development of some disease process. This simply means that a food that may be harmful to the cells of one person may be beneficial to the cells of another. Therefore, by identifying whether foods are beneficial, neutral or toxic to a particular blood type, it is possible to develop the optimal diet for individual clients.
Sounds simple, but what does it mean in practice? To understand the basis (and the implications) of the lectin story, we need to revisit some history. Let’s begin by talking about the diets of our earliest ancestors, the hominids or man-like creatures who emerged from the forest and took up residence on the African savannas. These people were opportunistic hunters and gatherers, eating whatever animal flesh was freely (if the hunting skills of the men of the tribe were finely honed) or not so freely available (in the case of those who were less skilled or just plain unlucky). Fish was another source of protein, and since it could be caught relatively easily if a small dam was built or a net thrown, it was often a more reliable food source than game meat. Insects were eaten too, and the men of the tribe also raided birds’ nests to collect the eggs. The flesh, fish, insects and eggs that were caught and gathered by our male ancestors were eaten with the vegetables, fruit, berries, nuts and seeds that were collected by the women of the tribe. It seems quite likely that the foodstuffs procured by the women were the mainstay of the diet, and that these societies would be accurately named "gatherer/hunters."
Be that as it may, for a few million years, mankind gathered and hunted or hunted and gathered on a daily basis. His search for food occupied the major part of his waking hours. However, his food was grown on healthy soil, was completely uncontaminated, was freshly picked or caught and was always "in season." As he became more sophisticated, he learned that cooking, drying, smoking or salting foodstuffs could extend their life, but even those changes did little to alter the basic range of produce that were his dietary staples. The "caveman" diet certainly seems boring by today’s standards, but we should always remember that it was one that sustained man for three or four million years (depending on which paleontologists you study), so it was clearly a diet that was well suited to his needs. Let’s look at the foods that made up that diet:
- Animal/bird flesh
Then something happened that changed the content of that diet dramatically. About 10,000 years ago, a quiet revolution occurred that heralded the demise of these gatherer/hunter societies. Man discovered that he could cultivate grains and could subsequently harvest and store quantities of food that would sustain him through the winter months and through periods of famine. With the planting and cultivation of seed grain, mankind (and womankind) was freed from the constant round of food gathering and hunting that had been their lot for a few million years.
At this point, it’s probably worth considering the evolutionary timeline of man to gain some idea of where the agricultural revolution sits in the grand scheme of things. David Christian, associate professor of history at Macquarie University in New South Wales, Australia, is writing a book on what he calls "Big History." He has dated the beginning of history at the Big Bang that occurred about 13 billion years ago, and so that his readers can clearly see where our human history sits, he has compressed those 13 billion years into the 13 years ending at midnight on December 31, 1999. Using this chronology, the first homosapiens appeared about 11.07pm on December 31. The first farmers lived in the Middle East from about 11.55pm, the first urban civilizations appeared in Mesopotamia (now Iraq) about 11.57pm, classical civilizations of China, Persia, India and the Mediterranean flourished at 11.59pm and the Industrial revolution introduced modern civilizations at six seconds to midnight!
If nothing else, this timeline should give us all cause to stop and think about our place in the bigger order. We are not even a blip on the evolutionary time line! It can also clearly demonstrate the very short space of time we have had to adapt to the dramatic changes in our diets, the first of which was precipitated by the agricultural revolution. At around the time man first became aware of the benefits of growing, harvesting and storing grain, the archeological records reveal some startling changes. Skeletal remains show that with the introduction of grains to the hunter/gatherer diets, there was a dramatic increase in conditions that were linked to malabsorption, and there was also a marked decrease in the stature of individuals.
Then evolution intervened. There was a genetic mutation that saw the evolution of blood group A. Until now, the hunters and gatherers all had one blood type: O. But the evolution of group A allowed those with that blood type to tolerate and absorb grains. Those with this blood group were also much more resistant to the diseases such as plague, smallpox and cholera, which became a dominant feature of communal, and later, city dwelling. A further adaptation (blood group B), among the pastoralists and herders, allowed the absorption of dairy products and beef. Finally, a fourth adaptation, AB, allowed individuals with that blood type to tolerate both grains and dairy products. Since our modern Western diets are abundant in both grains and dairy products, you might be forgiven for thinking that type AB would now be predominant in Western society. Yet it remains quite rare; only five percent of individuals have this blood type. Of course, it’s probable that if we were to survive for thousands more years, we would see an increase in the numbers of individuals with type AB blood group, but in the meantime, 95 percent of us have a blood type that is not particularly well suited to modern diets.
In a nutshell, this means that if you’re:
- Blood Type O, you should eat the caveman hunter/gatherer diet (see above).
- Blood Type A, you can eat grains but should avoid dairy.
- Blood Type B, you can eat dairy but should avoid grains.
- Blood Type AB, you can eat both grains and dairy (in moderation).
This is the blood group diet at it’s very simplest. It can actually be broken down further. Taking each blood group, there are specific foods to avoid, foods that are neutral and foods that should be eaten for good health.
As I’ve mentioned, eating for your blood group can also be used effectively for weight management. In many individuals, weight gain is related to inefficient utilization of nutrients. This is really self-induced toxicity. (Remember, if your body is carrying an accumulation of toxic products, certain biochemical processes will work to keep you fat). If nutrients are inefficiently utilized, the toxicity actually comes from an accumulation of the intermediate products of your body’s own metabolic processes. Removal of the foods that lead to this accumulated toxicity results in improved metabolic efficiency and weight loss.
Finally, the various blood groups also differ significantly in their response to physical exercise.
The best exercise for each blood type is shown below:
- TYPE A: Tai chi, Hatha Yoga, hiking, swimming, biking
- TYPE O: Vigorous and intense physical exercise
- TYPE B: Moderate activities involving other people. These individuals do not do well when the sport is fiercely competitive.
- TYPE AB: Tai chi, Hatha Yoga, hiking, swimming, biking
So if you’ve got clients who are having difficulty losing weight, if they’re really not enjoying their exercise program, if they’re suffering from a chronic complaint, take heart. There could be a good reason for it! Find out their blood type and try a new approach.