[lurkerperpetual]

A very interesting topic for a study would be similarly testing groups of omnivores, vegetarians and vegans, to see if there are any detectable mental capacity differences. It should be less controversial than comparing the same between races and genders.

The 'we developed bigger and better brains from eating meat' is an often used rationale for the omnivore diet.

[araneae]

Actually, I think that would be a terrible study. It's too hard to control for other factors that may differ between the groups. For instance, vegetarians and vegans in the U.S. are on average more educated. You can add that into a model, but this kind of study- where you test people before, during, and after creatine addition- is really much better science.