Have you ever wondered about your blood type? It’s a valuable piece of information for many reasons, including if you needed blood in an emergency.

But it can also give you valuable lifestyle and dietary guidance.

Dr. Peter D Adamo first wrote about how blood type can be used to fine-tune the diet and to guide forms of exercise. His approach is based on the theory that eating according to type reduces the clot-forming chemicals in our blood, preventing strokes and heart attacks.

While I don’t embrace every aspect of his theory, I do apply the general recommendations, which I have highlighted below. Since his approach is based on the effect of lectins on the blood, I don’t agree with his micromanagement of fruits and vegetables. Lectins are compounds in grains, vegetables, and legumes that he warns cause agglutination or clumping of the blood cells. These lectins, however, are broken down by cooking, especially with water, by fermentation, and by sprouting. Rarely do we eat raw grains, for example.

The successful way I’ve applied his theory over the years is utilizing the big picture: how much protein people should be getting and from what sources and what types of exercise suit them the best.

In summary, here’s what I’ve learned in working with thousands of clients over the years:

Blood Type O: the universal donor and most common blood type have the hardiest constitution. These were the original humans, the cavemen or the hunters-gathers, and they do best when they eat the ancestral diet.

If you have O Blood Type, your diet should consist of anything the original humans could have hunted, fished, dug from the ground, or picked from a bush.  In other words, your best choices include meat and potatoes, nuts and seeds, root vegetables, fruits.  They have strong stomach acid and can easily digest meat.

They have success as vegetarians, but and they don’t tolerate dairy or grains as well as other types.

I have also noticed over the years that some blood types are more sensitive to eating according to type than others. Ironically, despite its strong constitution, an O blood type eating a vegetarian diet are the people who do worst.

“O’s” need vigorous exercise such as running, biking, spin classes, and aerobics. They tend to be stress hardy.

Blood Type A: these are the farmers who came later. They can do limited grains, need less protein, and can eat soy and complementary proteins. “A’s” can be vegetarian or vegan without any problem. They have less stomach acid and can be prone to digestive upset.

The “A”s need a routine schedule of sleeping and waking hours because of their more sensitive nervous system. For