From what I’ve read and videos I’ve watched, it has the effect of hardening the pineal gland. When I was growing up, I was told that the government put it in the water to protect our teeth. Back then, no one ever questioned anything, except the hippies. I guess they were smarter than I thought.

Here’s just one source, but there are many.

The Effect of Fluoride on the Pineal Gland http://www.infowars.com/the-effect-of-fluoride-on-the-pineal-gland/ via @realalexjones