We are the descendants of hunter-gatherers. Ancient populations in Europe and parts of Asia would have not have survived without meat. This is a historical fact, because the cold environment during ice ages made growing vegetables, grains and fruits, etc., impossible. We are adaptable. Nature has also given us the type of teeth that can chew meat.

A child that is raised vegetarian is very likely undernourished, because children require many of the nutrients that are not readily available in sources other than meat. This can be very dangerous, and is a form of child abuse.

Allergies and intolerances to certain grains, flour, fruits, nuts, dairy and vegetables are very common. Autoimmune and other abnormal reactions to meat are rare.