Vegetarians Are Freaks of Nature
Not sure how credible this source is, but the article is an interesting addition to what I've been saying for years. We are on top of the food chain; don't give it up.
Just look at our teeth versus bona fide herbivores like cattle and deer. Their teeth are all broad and flat - good for chewing soft stuff and not much else. We have teeth made for cutting and tearing tough stuff AND teeth for grinding it up before swallowing.
Millions of years of evolution is a good enough reason for me.