A Positive Blood Type

The blood type diet is something you may have heard about. Although I believed it was long since debunked, patients continue to ask about it, so I decided to learn more.

What is the Blood Type Diet?

Peter D’Adamo was a naturopathic doctor who published a book that described how people could live longer and be healthier by eating according to their blood type. Your blood type should dictate your choice of condiments, spices, and even how you exercise. The book became a bestseller and people all over the world were using it to find out their blood type and revise their grocery lists. This helped them make changes in their eating habits, exercise, and think about their health.

These are some recommendations based on the “Eat Right For Your Type” diet.

• People with type O blood need to eat high-protein foods. They should eat lots meat, vegetables and fish. Limit grains, legumes, beans and legumes. For weight loss, seafood, red meat, fish, vegetables, olive oil, and broccoli are the best. Avoid dairy, wheat, and corn.
• People with type A blood need to eat fruit, vegetables, meat, tofu, seafood, chicken, turkey, whole grains, and other foods. Vegetables, tomatoes, avocados, and olive oil are the best options for weight loss. Avoid dairy, wheat and corn.
• People with type B blood need to eat a variety of foods, including meat, fish, dairy, seafood, and grains. Type B people should eat green vegetables, eggs and liver to lose weight. They should also avoid wheat, corn, peanuts and wheat.
• People with type AB blood can eat dairy products, tofu and lamb, as well as grains, fruits, and vegetables. Tofu, green vegetables and kelp are the best options for weight loss. However, chicken, corn and buckwheat should be avoided.

The recommendations for blood type diets go beyond food choices. People with type O blood should exercise with high intensity and take supplements to their sensitive stomachs. Those with type A blood should engage in low-intensity activities, including meditation, and choose high quality aerobic exercise .

Is it possible to eat for your blood type?

Peer-reviewed medical literature has not published high-quality research on the blood type diet. A search for the name of the author in medical literature does not reveal any research on this diet. It is worth noting the 2013 and 2014 blood type diet studies. The 2013 study reviewed the medical literature worldwide and found no evidence of a blood type diet’s benefits. The 2014 study showed that people who followed any blood type diet had some improvement in their cardiometabolic risk factors, such as blood pressure or cholesterol. However, these improvements were not related to their blood type. A 2021 study on people who ate a low-fat vegan diet showed no correlation between blood type and lipid levels, or any other metabolic measures.

Is it logical?

This diet assumes that our blood type is directly related to our ability to digest certain foods. The proper diet will therefore improve digestion, prevent diseases such as cancer and heart disease, and increase energy levels.

Type O is the “ancestral” blood type that was inherited from the hunter-gatherer ancestors. It had a diet high in animal protein. According to some, Group A evolved when humans started to farm and ate more vegetarian food. The Group B blood types were thought to have originated in nomadic tribes that ate a lot dairy products. Because Group AB blood was thought to have been formed from people of types A or B blood, type AB recommendations were intermediate among those for people with types B and A blood.

Each theory has been challenged. There is evidence to support the theory that type A was not the first blood type to evolve in humans. There is also no connection between blood type, digestion, or any other factors. There is no evidence to support the diet’s effectiveness. However, there are serious questions about its validity.

What’s the downside to this?

This is a valid question, especially considering that some improvements were observed in those who followed certain blood type diets (see the link above). Knowing your blood type is essential before you can eat based on it. Then, you will need to follow a restricted diet. It is possible that personal preferences can be a problem. A vegetarian who has type O blood might have trouble adhering to the prescribed diet. Red meat-lovers may be disappointed to discover they have type B blood. The recommended supplements are expensive, as are the organic foods. A nutritionist can provide better evidence-based recommendations than your blood type if you have high cholesterol or diabetes.

What now?

Advocates for blood type diets might argue that even though the perfect study hasn’t been done, it doesn’t mean they are ineffective. These diets have not been proven to be harmful. My guess is that the interest in blood type diets won’t fade anytime soon. There’s a reason why there are so many books about diet in bookstores. Each one claims to be the best, if not the most effective. It’s impossible to know the best diet for every person. Even if we could, it is difficult to stick to one diet.