Tooth decay is a health problem that has affected humans for centuries.
Decay often meant pain, infection, loss of time from work or school, and inability to chew foods properly. Fortunately, fluoride and its benefits were discovered in the 1930s when scientists observed remarkably low decay rates among people whose water had naturally significant amounts of fluoride. Clinical studies in the 1940s and 1950s confirmed that a small amount of fluoride added to community water supplies would decrease the number of new cavities, especially in children. The most inexpensive way to deliver the benefits of fluoride to all residents of a community is through water fluoridation. All water contains some fluoride naturally.