In 1996, naturopathic physician Dr. Peter J. D’Adamo wrote The New York Times best-seller Eat Right 4 Your Type, which is based on the notion that people of different blood types—O, A, B or AB—are healthier and perform better on certain diets. Since then, the topic of whether or not you should be eating for your blood type continues to be debated.
Though “The Blood Type Diet” isn’t new, nutritionist Jennifer Hanway says it resurfaces every few years as the next diet trend to try. “There is very little sound scientific evidence to back up the benefits of eating for your blood type, and the reported improvements from those that follow this way of eating most likely come from the fact that it encourages a whole food–based diet with minimal processed foods,” she explains. “This is something we can all benefit from, regardless of our blood type.”
Dr. Kellyann Petrucci, nutrition expert and author of Dr. Kellyann’s Bone Broth Breakthrough, says the Blood Type Diet trend is not based in research. “A 2015 study of 1,455 participants did not support the hypothesis that when individuals eat according to their ABO blood group, they improve their health and decrease risk of chronic diseases such as cardiovascular disease,” she explains. “In a more recent 2020 study published in the Journal of the Academy of Nutrition and Dietetics, experts also negated the idea that you should be eating for your blood type.”
In Hanway’s consultations with clients, blood type is not part of the equation. “There are many factors to consider when giving personalized diet recommendations, including health history, family history, genetics, gut health, hormone balance, nutrient deficiencies, stress levels, and quality of sleep,” she says. “I look at many biomarkers to inform my recommendations, but blood type is not one of them.”