Because after they started fluoridating , kids cavity rates increased. By contrast, rates in the rest of fluoride-free Europe declined. So why, you many ask, did anyone fluoridate in the first place? Fluoride is a by-product of aluminum productions. Aluminum producers must dispose of it. But...
This trend has occurred regardless of the concentration of fluoride in water or the use of fluoridated salt, and it probably reflects use of fluoridated toothpastes and other factors, including perhaps aspects of nutrition. Tooth decay …