Researchers from the University of Toronto (U of T) have found that the theory behind the popular blood type diet--which claims an individual's nutritional needs vary by blood type--is not valid. The findings are published this week in PLoS One.
"Based on the data of 1,455 study participants, we found no evidence to support the 'blood-type' diet theory," said the senior author of the study, Dr. Ahmed El-Sohemy, Associate Professor and Canada Research Chair in Nutrigenomics at the U of T.
"The way an individual responds to any one of these diets has absolutely nothing to do with their blood type and has everything to do with their ability to stick to a sensible vegetarian or low-carbohydrate diet," said El-Sohemy.
Researchers found that the associations they observed between each of the four blood-type (A, B, AB, O) diets and the markers of health are independent of the person's blood type.
The 'blood-type' diet was popularized in the book Eat Right for Your Type, written by naturopath Peter D'Adamo. The theory behind the diet is that the ABO blood type should match the dietary habits of our ancestors and people with different blood types process food differently. According to the theory, individuals adhering to a diet specific to one's blood type can improve health and decrease risk of chronic illness such as cardiovascular disease. The book was a New York Times best-seller that has been translated into 52 languages and sold over 7 million copies.