Have you ever been curious about the blood type diet? This week, Nutrition Diva reviews the controversial method on her podcast.The blood type diet was proposed by naturopathic physician Peter D’Adamo way back in the 1990s. His book Eat Right For Your Blood Type was a best-seller. The basic idea is that your blood type may be the key to what type of diet is best for you, and that you won’t feel as well or be as healthy if your diet is inappropriate for your blood type.

The different blood types—O, A, B, and AB—are genetic variations that appeared at various points in human evolution. Type O blood is thought to be the oldest surviving blood type, corresponding with the hunter-gatherer period. Type A blood appeared roughly twenty thousand years ago, coinciding with the dawn of primitive agriculture and the introduction of things like legumes and cereal grains to the human diet.

The other blood types emerged even later, when humans were not only farming but also keeping livestock and consuming dairy products. They’d also begun to travel the globe, interbreed, and encounter a much wider variety of food species.

Dr. D’Adamo’s central hypothesis is that you will be best nourished by the diet that was predominant when your blood type emerged. In other words, Type O folks thrive on lots of meat and very few grains and dairy products. People with Type A blood will be healthier eating a more plant-based diet. Lucky Types B and AB get to eat a wider variety of foods. In his books, he’s laid out detailed lists of foods that are good and bad for each blood type.

It’s a very interesting hypothesis, but unfortunately for a long time it only had anecdotal evidence to support or disprove it. Recently though, new research has been done. To hear Nutrition Diva's full analysis of that research and whether she recommends matching your diet to your blood type, listen to the full episode here.