The blood type diet is a nutritional diet advocated by Peter D'Adamo, a naturopathic physician, and outlined in his book Eat Right 4 Your Type. D'Adamo claims that ABO blood type is the most important factor in determining a healthy diet, and he recommends distinct diets for each blood type.

What is Blood Type Analysis, and how would I apply this method to my every day life? For example, people with blood type O will be most healthy if they maintain a high-protein diet with vigorous exercise, while people with blood type A should follow a vegetarian diet with less strenuous physical activity.

The appropriate diet and lifestyle also depend on the body's current state of health.