It's one of those things we'll probably never have a conclusive answer to and even if we do it'll depend on when you decide to look at the diet to decide what w

It's one of those things we'll probably never have a conclusive answer to and even if we do it'll depend on when you decide to look at the diet to decide what we are 'evolved' to handle. At some times we may have been more meat heavy and others more grain/berry/etc heavy.