Baloney!
There are excellent reasons to be a vegetarian, but none of these is one of them.
Good health is.
That is not “nn-vegs”.... that is “liberals” dude
If someone is aware of how to balance a vegetarian diet so they still have an intake of nutritional elements which most people derive from meat or other animal sources then it can be healthy. But it's my personal observation that most western vegans are surly, weak, listless, pale and sunken eyed, and in some cases resemble recently released concentration camp survivors. They are not what I'd describe as "healthy".
We may be primates but that doesn't mean we have the same digestive track and nutritional needs as the (other) great apes. Plus, even chimpanzees, our closest cousins, hunt and eat meat when the opportunity presents itself. I think it usually comes down to someone taking a moral stand that the killing of anything with a brain and big brown eyes (broccoli noticeably lacks both) is wrong.