Personal experience says religious folks are more prone to mental diseases

[Astonished]

Yeh.  "Disease" in mental terms isn't an issue of belief-- it almost always talks about function/dysfunction.  You can believe any goof shit you want, but if you get out of bed every morning, go do your job, and for the most part abide by the laws of the land, you aren't diseased.

What we're talking about is fostering madness where either only small seeds exist or none at all. If you lock someone in a room, tell them the worst possible things they could hear about themselves for years, tell them they're never getting out of there, and give them reason to fear an even worse fate, well, what exactly is that going to do to their mental state? Bend it completely out of shape, and in some cases, it's going to snap. So even in cases of nurture rather than nature, someone can be driven over the edge. Now, just imagine this locked room scenario is happening only within their mind as a result of religious indoctrination, and you get reality denial and Pat Robertson to name a few, and depression, anxiety and other avoidable problems that wouldn't have cropped up in the absence of that cross-shaped girder thrown into the gears of their brain.