Most people think of blood groupings in terms of transfusion, but in fact a great deal of research has linked ABO groups with disease-susceptibility and diet.

The Blood Type Diet is a diet plan designed for you! Because it's specified for your blood it helps you digest and absorb food better, as well as aid with weight loss.

According to the book “Eat Right for Your Type” written by Dr. Peter J. D’Adamo, a weight-loss strategy for every individual should take into consideration his blood type. The blood type provides the key to the body’s immune, metabolic, and hormonal systems.

In his book “Eat Right for Your Type”, Dr. Peter J. D’Adamo offers a revolutionary theory of nutrition, which is based on four blood types. Although the theory is not specifically designed for weight loss, people following the recommendations of Dr. D’Adamo naturally lose excess weight and achieve optimum performance.

The author of a popular diet book “Eat Right for Your Type”, Dr. Peter J. D’Adamo, states that healthy weight can be achieved by eating in accordance with our blood type. People gain weight because they eat wrong foods - the foods, which can be harmful for their blood type genetics.

The blood type diet is a diet advocated by Peter D'Adamo and outlined in his book Eat Right 4 Your Type. Its basic premise is that ABO blood type is the most important factor in determining a healthy diet. The diet is widely derided by dieticians, physicians, and nutritional scientists as having no scientific basis.The cornerstone of his theory is D’Adamo’s premise that lectins in foods react differently with each ABO blood type. Throughout his books he cites the works of various biochemists and glycobiologists who have researched blood groups, claiming or implying that their research supports this theory. In his book, Eat Right 4 Your Type, “Lectins: The Diet Connection”, and in following chapters, "lectins" which interact with the different ABO type "antigens" are described as incompatible and harmful, ergo the selection of different foods for A, AB, B, and O types to minimize reactions with these lectins.D'Adamo bases his ideas on the ABO classification of Karl Landsteiner and Jan Janský, and some of the many other tissue surface antigens and classification systems, in particular the Lewis antigen system for ABH secretor status. The evolutionary theory of blood groups, which is also 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 book Genetics and the races of man: An introduction to modern physical anthropology, published in 1950, Boyd describes how by genetic analysis of blood groups, human races are populations that differ according to their alleles. On this basis, Boyd divided the world population into 13 geographically distinct races 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 believed by D'Adamo to be the hunter, the earliest human blood group. The diet recommends that these supposedly muscular, active people eat a meat-rich diet.Blood group A is called the cultivator by D'Adamo, who believes it to be a more recently evolved blood type, dating back from the dawn of agriculture. The diet recommends that individuals of blood group A eat a diet emphasizing vegetables and free of red meat, a more vegetarian food intake.Blood group B is, according to D'Adamo, the nomad, associated with a strong immune system and a flexible digestive system. The blood type diet claims that people of blood type B are the only ones who can thrive on dairy products.Blood group AB, per D'Adamo, the enigma, the most recently evolved type. In terms of dietary needs, his blood type diet treats this group as an intermediate between blood types A and B.