"The high levels of fluoride that occur naturally in some drinking water can cause tooth and bone damage and should be reduced, the National Research Council said Wednesday."
Seems mankind is once again saying God you did it wrong. Not that what naturally occurs is now bad for us and we need to clean up nature.
Maybe I'm misunderstanding what you've said here and I don't mean disrespect, but flouride does not "naturally" occur in drinking water in the levels that come out of your tap. It is added.
Well, nothing to excess. Like the story of a politburo member who took the course of hypnosis treatment for his incontinence. The treatment was so successful that after it he wasn't able to urinate at all - and burst. ["Yawning Heights"]