Blood Type Diet - Description

Description

D'Adamo's premise is that blood type is key to the human body's ability to differentiate self from non-self. Lectins in foods, he asserts, react differently with each ABO blood type and, to a lesser extent, with an individual's secretor status. In "Lectins: The Diet Connection" and subsequent chapters of Eat Right 4 Your Type, lectins which interact with the different ABO type antigens are described as incompatible and harmful, and that the selection of different foods for A, AB, B, and O types is therefore important in minimizing reactions with these lectins.

D'Adamo bases his ideas on the ABO classification system of Karl Landsteiner and Jan Janský, as well as some of the many other tissue surface antigens and classification systems, particularly the Lewis antigen system for ABH secretor status.

On page 20 of Eat Right 4 Your Type, D'Adamo states, "At this point, you might be wondering about other blood type identifiers, such as positive/negative, or secretor/non-secretor. ... These variations or subgroups within blood types play relatively insignificant roles. More than 90% of the factors associated with your blood type are related to your primary blood type, O, A, B, or AB."

The evolutionary theory of blood groups used by D'Adamo stems from work by William C. Boyd, an immunochemist and blood type anthropologist who made a worldwide survey of the distribution of blood groups. In his 1950 book Genetics and the races of man: An introduction to modern physical anthropology, Boyd describes how through genetic analysis of blood groups, modern humans can be categorized into populations that differ according to their alleles. Boyd divided the world population into 13 geographically distinct species with slightly different frequency distributions of blood group genes.

D'Adamo groups those thirteen races together by ABO blood group, each type within this group having unique dietary recommendations:

• Blood group O is described by D'Adamo as the hunter. He recommends that those of this blood group eat a higher protein diet. The group is alleged by D'Adamo to be the first blood type and to have originated 30,000 years ago, although research indicates that blood type A is actually the oldest.
• Blood group A is called the agrarian or cultivator by D'Adamo, who believes this type dates from the dawn of agriculture, 20,000 years ago. He recommends that individuals of blood group A eat a diet that emphasizes vegetables and is free of red meat, a diet more closely vegetarian.
• Blood group B is called the nomad by D'Adamo, who estimates this group to have arrived 10,000 years ago. He states that this type is associated with a strong immune system and a flexible digestive system. He also asserts that people of blood type B are the only people able to thrive on dairy products; this is contradicted by the fact that while people with blood type B tend to be from Asia (specifically, China or India), lactose intolerance is most common among people of Asian, South American, and African descent and least common among those descended from northern Europe or northwestern India.
• Blood group AB is described by D'Adamo as the enigma, who believes it to be the most recently evolved type and to have arrived less than 1,000 years ago. In terms of dietary needs, he treats this group as an intermediate between blood types A and B.