Anthropologically speaking, we evolved primarily as herbivores but the majority of our ancestors who survived the last ice age adapted to become omnivores. So at this point in our evolutionary development, we are technically omnivores, but we are much closer to herbivores than carnivores if you look at our digestive track.

Im 100% vegan, and I like being this way. I dont think that most people require meat to be healthy, but there are certain human populations such as the Inuit who have a much much harder time subsisting on a vegan diet than other populations. It is thought by many that people with Type A blood do best on a vegan diet, and type B can go either way, while type O have the hardest time on vegan diets and are more prone to iron deficiency.

This is disputed though. Not everybody believes in the blood type diets, but I have seen anecdotal evidence to support this.