This varies among states, ranging from 8.5% of the population in Hawaii to 100% of the population in Washington, D.C. Water fluoridation is not mandatory, and while there is a recommended fluoride concentration in drinking water (0.7 milligrams per liter ...

Dental experts say the amount of fluoride added to water is effective in reducing tooth decay and safe; others say it’s not needed.

The Washington Post and other media noted that medical organizations responded by calling Kennedy’s assertions unfounded at the levels of fluoridation used in drinking water. But many of them have also noted that in an NBC interview, Trump said possible action against fluoridation of water “sounds OK to me ... You know, it’s possible.”