You got me - I haven't read his books thoroughly either, just a few chapters.
I don't have references on hand, but I believe there's a fair amount of accepted research that shows that we eat far more meat (and probably dairy) than is good for us - some meat gives protein and other good things, but you go too far and your body starts processing all the fats and whatnot in unhealthy ways. The evolutionary standpoint certainly supports this - we evolved as primarily hunter-gatherers who would manage to kill an antelope once every two weeks or something. Agriculture changed our diets significantly, and not necessarily for the healthier (an interesting writer on this subject is Jared Diamond).
I don't have references on hand, but I believe there's a fair amount of accepted research that shows that we eat far more meat (and probably dairy) than is good for us - some meat gives protein and other good things, but you go too far and your body starts processing all the fats and whatnot in unhealthy ways. The evolutionary standpoint certainly supports this - we evolved as primarily hunter-gatherers who would manage to kill an antelope once every two weeks or something. Agriculture changed our diets significantly, and not necessarily for the healthier (an interesting writer on this subject is Jared Diamond).