Fluoridation is the addition of a chemical called fluoride to water supplies to help teeth resist decay. In the 1930’s, researchers discovered that people who grew up where water naturally contained fluoride had up to two-thirds fewer cavities than people living in areas without fluoride in the water. Newburgh, New York, and Grand Rapids, Michigan, began to fluoridate their water in 1945, as an experiment. By the 1950’s, the tests showed that the incidence of tooth decay had decreased in these cities, and United States public health officials recommended fluoridation for all communities.
Today, about half the people of the United States drink fluoridated water. In most other countries, fluoridation is not used as widely as it is in the United States. The use of fluoride tablets and toothpastes and the application of strong fluoride solutions to the teeth by dentists can also help prevent tooth decay.
Local governments or the people of a community often must decide whether the water supply should be fluoridated. This means balancing the benefits, risks, and costs of fluoridation, as well as moral questions about its widespread use. People disagree over these issues, and fluoridation has always been controversial.
Benefits, risks, and costs.
Many studies have shown that fluoridation reduces tooth decay substantially. However, rates of tooth decay also have declined in areas without fluoridated water, perhaps chiefly because of the widespread use of fluoride toothpastes.
Excessive fluoride intake can be harmful, especially to the bones and teeth. In India and other countries, for example, bone damage has occurred in people whose drinking water contained fluoride levels from 2 to 3 parts per million (ppm) or more. The level most commonly used in fluoridated water is 1 ppm. In the United States and elsewhere, mottling (discoloration) of the teeth becomes more common as the level of fluoride in drinking water increases. Even at the fluoride level recommended for fluoridation, some people develop white flecks or patches on their teeth.
Some scientists believe that fluoridation involves special risks for people with kidney disease and for those particularly sensitive to toxic substances. However, ill effects from fluoridation have never been shown to be widespread. Most experts believe that the risk of harm from fluoridation is quite small.
Most U.S. public health officials and dentists favor fluoridation. They believe it provides important benefits and involves little or no health risk. Supporters also argue that fluoridation gives the whole community fluoride protection simply, effectively, and at a small expense compared with the costs of treating tooth decay.
Controversies over fluoridation.
Since the 1950’s, fluoridation has sparked much political controversy. Heated debates erupt when communities consider fluoridating their water supplies. Over the years, about 6 of every 10 communities voting on fluoridation have rejected it. Many people object to fluoridation because they prefer not to take any risks associated with it, even if the risks are very small. Some people feel they have a right to make their own choices in health matters, and that a community violates this right when it adds fluoride to its water supply. On the other hand, if water is not fluoridated, people may suffer tooth decay that easily could have been prevented. Many people feel that this result is also unacceptable.
See also Fluorine; Teeth (A good diet); Toothpaste and toothpowder.
