A naturopath called Peter D’Adamo popularized the idea that a any diet based on blood type could help a person achieve good overall health and reduce the risk of developing certain diseases. For example, it is proposed that those people with type O can tolerate certain meats while those with type A should avoid meat in general. Are there any health benefits associated with this type of diet – vegan or otherwise?
However, research on the effects of a blood type diet is scarce, and the studies available have not proven its effectiveness. For example, the authors of a 2014 study concluded that their findings did not support the claims that a blood type diet provides specific benefits.