If you’re having trouble losing weight, avoiding illness, or tolerating certain foods, you might be eating wrong for your genetics, according to naturopathic physician Peter J. D'Adamo. In 1996, D’Adamo introduced his “blood-type diet” plan in his book Eat Right 4 Your Type. The widely published New York Times bestseller gained the attention of multiple celebrities, including Hailey Bieber (née Baldwin) and Miranda Kerr. However, as with many diets on the market – the blood type diet is not without its share of contention.

D’Adamo claims that by eating—and limiting—certain foods based on your blood type, you’ll harness your body’s natural ability to digest nutrients, burn fat, fight inflammation, and achieve overall health and wellness. He also believes that individuals with different blood types are prone to different diseases and levels of stress. “Research indicates that your blood type is a key genetic factor that influences many areas of health and well-being,” his website states.

What’s the Diet For Your Type?

According to D’Adamo, what to include and avoid in your diet all comes down to your blood type. These are some of the recommendations he makes in his book:

Type O

Type O blood is said to be the “original” blood type of the earliest humans. Called the “Hunter,” this type is susceptible to problems such as high acidity, inflammation, and hypothyroidism. Foods like dairy, grains, caffeine, and alcohol should be avoided. However, lean high-protein foods, including seafood and grass-fed red meat, are recommended. People with type O blood should also limit salt intake to optimize their thyroid function.

Type A

Individuals with blood type A can be prone to heart disease, cancer, anemia, and liver and gallbladder problems. Known as the “Agrarian,” they can benefit from eating a traditional vegan or vegetarian diet (or at least limiting meat and dairy) and reducing certain beans and wheat, while increasing their intake of soy, pineapple, and vegetables. People with type A blood can have a harder time breaking down red meat due to lower levels of stomach acid.

Type B

Someone with Type B blood may be more likely to develop autoimmune disorders. Referred to as the “Nomad,” they may benefit from a mixed diet of meat, certain legumes, and vegetables, with an increased focus on eggs, licorice tea, and certain meats, like venison. Foods like corn, lentils, chicken and certain grains should be limited.

Type AB

This is the most adaptable of all the blood types, with a combination of elements of both Type A and Type B. Dubbed the “Enigma,” it’s recommended that the diet of these individuals should be a mix of meat, veggies, dairy, fruit, and legumes, with a focus on moderation. Red meat, certain beans, seeds, and buckwheat are some items to be reduced. Type AB blood is also the most recently-discovered blood type, and rarest, with less than 5% of the global population reported to have type AB blood.

Scientific Evidence Behind the Blood Type Diets

Although D’Adamo’s website is filled with glowing success stories, certain scientists have failed to see proof of this diet’s efficacy. A 2014 study of 1,455 individuals by researchers at The University of Toronto found no evidence to support the theory that eating for a blood type has benefits. Although some individuals showed markers of better health after following the diet during the study period, the researchers concluded that the improvements weren’t necessarily related to the individual’s blood type. “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 researcher Dr. Ahmed El-Sohemy.

Not much more research has been done on the topic, but that doesn’t mean the idea is unfounded, incorrect, or harmful. A study done in 2013 by the American Journal of Clinical Nutrition found that not enough data has been collected to prove whether or not following these types of diets will work.

The Bottom Line

The blood type diet may seem intriguing, but there’s simply not enough research done on the topic to support a definitive conclusion. Whether or not you think following this type of diet will help you lose weight, it’s important to always consult with your health care team before beginning a new diet regimen.

One of IIN’s core concepts is bio-individuality, which means there’s no one-size-fits-all diet, and it’s important to find the way of eating that works for you. By enrolling in our Health Coach Training Program, you can learn the pros and cons of more than 100 dietary theories so help you find the foods and lifestyle that make you feel your best – and allow you to help others feel their best, too.