PT on the Net Research

Blood Type Diets


I am studying metabolic typing, and the subject of eating for your blood type keeps coming up. Does anyone have any information about this?


As a PhD trained nutrition and exercise specialist and long time coach of all sorts of people from elite athletes to recreational exercisers, I’ve been interested in both metabolic typing and blood type eating for many years. Clearly, with both types of eating, there are many people who swear by them. And this makes good sense. When switching to metabolic typing diets or blood type diets for that matter, food selection and overall caloric intake usually improves. This typically leads to some really great testimonials and case studies.

However, one never knows whether it’s the general improvement in food intake that’s made the difference or whether it’s the fact that a person is eating for his or her metabolic or blood type. Think about those folks who’ve never exercised or ate well in their lives and then start a full-blown exercise and nutrition regimen. They usually get great results. However, was it the new protein supplement that produced the results, their new fat burner, their new diet or their new exercise plan? It’s hard to tell since SO MUCH changed. Well, it’s often the same with metabolic typing or blood type diets. When a person becomes health conscious and starts following these diets, in addition to exercising and taking supplements, you have to wonder whether the diet did anything special or whether it was due to an improved diet and a new exercise routine.

When we turn to the research, we don’t get a clear answer. In fact, there’s only a small amount of support for metabolic typing and blood type diets. I won’t say there is NO research since there is definitely some peripheral work that MIGHT suggest that metabolic typing and blood type may impact nutrient tolerance. However, the picture is far from clear, and there is no definitive research in this area. So we’re left with the raving fans.

Now, don’t get me wrong. I never discount any plans with lots of real-world support. And I have tried metabolic typing and blood type diets with my clients. However, in the end, I’ve found that general improvements in three areas – food selection, food amount and food timing – are simpler to implement and just as effective as the plans discussed above.