I'd expect that if you ask a lot of people to post things that are true but which others deny for spurious reasons, you'd get the occasional thing which is true and denied for spurious reasons, and a whole lot of things which are believed with utter certainly and sincerity by that one person and are just wrong.

In other words, any idea listed here, including vegetarianism, is one which we ought to be skeptical of just by virtue of it being listed here. It's a simple Bayseian update on the probability that any given idea is right, given that this thread will predominantly be used to post wrong ideas.