A common argument I encounter from omnivores is that we have incisors, so are naturally designed to be carnivorous. I’ve always argued that those teeth had evolved to crunch insects and the occasional bit of rotten carcase, left over from a true carnivore’s meal. 

While it’s been around for a few years, I came across an interesting article about our ancestors’ diet. 

In short, it does back up my assertion that humans aren’t natural carnivores, but were instead mostly vegetarion; the truth is, for most of the last twenty million years of the evolution of our bodies, through most of the big changes, we were eating fruit, nuts, leaves and the occasional bit of insect, frog, bird or mouse.