interesting question...I just read Jared Diamond's evolutionary biology book and about a half dozen more in that field, and there's not a lot of agreement, even on the heels of the Human Genome Project, about how many biological significant ethnic, "racial" (or perhaps more correctly, continent-of-origin?) differences there truly are...but certainly there are some, or we wouldn't see the differences with sickle cell anemia, malaria resistance, skin cancer rates, etc. I mean, just look at that Pima Indian info about diabetes and obesity! Poor folks can't tolerate carbs OR over 1000 calories a day, apparently.

I am pretty skeptical about the "eat right for your type" book. But what I have found that is more convincing in my reading this past year is that basically, the darker your coloring, the less likely you'll tolerate dairy. This apparently has to do with it being people in northern climes who first domesticated animals for their milk. The rates of lactose intolerance among Africans (and African Americans) is very high; the rates among aborginal Americans is even higher. Following the paleo people's reasoning, lighter complexioned people probably are descended from long-time dairy-consuming folk and have had more generations to develop the digestive goodies necessary to process dairy.

Or maybe I just like that idea because I'm blonde and don't want to give up my dairy, even though I'm otherwise intellectually convinced I should! lol.

Anecdotally, my blood type is A, btw...the most recent, but I really cannot tolerate grains, and a vegetarian diet makes me weak as a newborn. More than a little olive oil gags me...is that genetics or habit? Dunno.

You may be right about your own diet and the reasons for it...we still have lots to learn about this whole topic.