Caution for vegetarianism

Humans probably evolved as an omnivore, and this is about the consensus view. But there are a lot of debate over the composition of HG's diet: was it slanted more toward animal products or plant products? So far the evidences point more toward the former. We have a relatively small gut and liver given our body size, so we have to eat nutrient and calorie dense foods, which implies animal products were playing an important role in HG's diet. Also it's just impossible to obtain all the essential nutrients from plants without supplements, especially those fat soluble vitamins. Yet another support comes from Weston Price's studies of healthy traditional people: none of them subsisted on plants only, though some of them(Inuit) completely lived without plants.

While I have tweaked my diet a bit more toward animal products, I still eat plenty of vegetables. For one thing I enjoy eating some vegetables, and more importantly, the animal products we eat today, mostly muscle meats, are not nearly as nutirent dense/complete as those eaten by HGs. As the result, we might have to eat some plant-based foods, even though it might not be the optimal way of getting these nutrients.