Hitler put it in the drinking water in countries they took over to keep the populous dumb, compliant and docile and these days we get it from China. What fluoride actually is, is the soot from inside a smoke stack and these days, especially from China, there is no way to know how much lead and other poison is in it. That is why there is a skull and cross bones on it. If you go to a hardware store and look up "rat poison" it is sodium Fluoride.

NOTE: these days they put fluoride fillings in your mouth, so make sure to ask for fluoride free fillings only! Of course countries that don't fluoride in water have citizens with better teeth and enamel.