Fluoride's benefits for teeth were discovered in the 1930s. Dental scientists observed remarkably low decay rates among people whose water supplies contained significant amounts of natural fluoride. Several studies conducted during the 1940s and 1950s confirmed that when a small amount of fluoride is added to the community water supply, decay rates among residents of that community decrease. Although these studies focused primarily on the benefits of water fluoridation for children, more recent studies demonstrate that decay rates in adults are also reduced as a result ot fluoride in the drinking water. 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.
When a community fluoridates its water, it adjusts the level of fluoride in the water to prevent dental decay. Currently, over 144 million people in the United States are supplied with water containing enough fluoride to protect teeth. The current level is 62 percent. To reach this goal, appoximately 30 million more people must gain access to fluoridated water through public water systems. Other sources of fluoride are also available.