I started a casual meditation practice a couple of years ago and was getting benefits from it, when I came across an article (on Hacker News) written by a man who had developed severe disassociation and other disorders from meditation.

The irony is that I started meditating because I struggle with panic disorder. Now I was hearing that my most common panic trigger (the thought that I could think myself crazy) was actually real! This sent me down quite a spiral that I have had to resolve by accepting the tiny odds that I might go spontaneously nuts. That's not an easy one, and I wish there was more reliable research on this issue.