Are Blood Type–Based Diets Just a Fad?


bloodIt seems that every time we turn around, there is a new diet that promises to get that weight off quicker, better and help you look great and feel great! Another promise a lot of the commercially promoted diets make is that they tend to promise that it will be easy. But what if there was a way of making dieting easier for you? What if your blood type made a difference in what you ate and could help you on your weigh loss journey and could make you healthier?

David L. Katz, MD, director of the Yale-Griffin Prevention Research Center and contributor answers the question of whether blood type-based diets actually work or not.

Here is his answer:

The premise of this plan is that your blood type indicates the prehistoric group you’re descended from, and it reveals what your digestive system can tolerate. Type O, the oldest blood type genetically speaking, supposedly indicates a need to eat meat every day because the earliest populations were hunter-gatherers. People with type A are descended from agrarian cultures and, the theory goes, should follow a vegetarian diet.

If that sounds a little wacky, it is—although blood type does have some influence on health. Researchers have known for years that type Os tend to be more susceptible to ulcers, for example. And food allergies or intolerances may be related to blood type.

But following this diet to the letter could deprive you of essential nutrients. Dairy and grains are pretty much off-limits for Os—the most common blood type. I probably don’t need to remind you that the calcium found in dairy is essential for healthy bones and that the fiber in whole grains can protect your heart.

In addition, the idea that we have the exact same dietary needs as ancestors who walked the savannas in 50,000 B.C. is extremely far-fetched, and helps explain why most respected medical experts do not support this approach. Worry about your blood type when you need a transfusion, not a meal.



  1. Dr. Katz is no more an expert on blood-type diets than I am about nuclear physics. If he or anyone else wants the facts on blood-type diets, go to the current authority: Dr. Peter J. D’Adamo. There are many people who admire and respect the expertise of Dr. Oz, the television celebrity. Dr. Oz is quoted as saying that “where all the rest of us have stopped, Dr. D’Adamo has gone a step beyond.”

  2. Pingback: Are blood type–based diets just a fad? | YNaija

Leave A Reply