This entire discussion is crap. It might as well be theology.
The human body is set up to accomodate ANY diet. We were once incapable of sustaining the same diet for long periods of time. The winter diet was fiercly different than the summer diet. The humans teeth are proof of this. We have incisors for ripping and tearing and we have cuspids for grinding. The body was able to adapt (ala Darwin!) to any given situation. We have both types of digestive systems (Small and Large Intestines) and we are able to live feast or famine.
Stop bitchin about right and not right! I don't mind vegetarians and even Vegans. Just don't talk to me about that damned Social Agenda that goes with Veganism. It is far too militant. If a cow could track us and kill us, it would! Survival of the fittest! The weak and the stupid all die off! We are the top of the food chain which gives us the Right to decide what happens. Live up to your destiny and quit crying about it. Who cares what food you eat. Next you will have a discussion about Nike vs. Puma.