Fluoridation: Questions & Answers

• Why is water fluoridated?
  Community water fluoridation prevents about 25% of tooth decay over an individual's lifetime, and brings about cost savings to the community from a reduction in dental care. Children especially benefit from drinking water fluoridation because their adult teeth are in the process of forming, and because they often lack the good brushing habits of adults. Adults also benefit from fluoridated water when teeth are exposed to beverages and food made with fluoridated water.
• What is fluoride?
  Fluoride is a naturally-occurring element in water that deters bacterial growth and improves the structure of tooth enamel to make it more resistant to decay, especially in young children. Fluoride is present to some extent in all water, food, and beverages, but the concentrations vary widely.
• Why should my water be fluoridated?
  The amount of natural fluoride in water varies widely from community to community. Some water needs no additional fluoridation to be effective against tooth decay. In areas with low or no fluoride concentrations, extra fluoridation helps give the water the same benefit of cavity prevention that other areas enjoy.
• What if my water system does not have a water fluoridation program?
  Ask your child's physician or dentist about receiving supplements for children through 8 years of age.
• Is there a difference between naturally fluoridated water and water that has had fluoride added?
  No. The dental benefits of optimally fluoridated water occur regardless of the fluoride's source.

  The benefits of fluoride were first noticed in areas where water was naturally fluoridated. By adding fluoride to water supplies that are fluoride-deficient, all water can enjoy the same protective benefits.

• How does fluoride prevent tooth decay?
  Fluoride's preventive effect acts in three main ways:
  • It reduces the amount of acid produced by bacteria that can decay teeth.
  • It makes tooth enamel less susceptible to acid by chemically strengthening it.
  • It promotes the repair of tooth enamel in areas that have been affected by acid.
• How effective is fluoridated water?
  Many studies over time have proved the effectiveness of water fluoridation.

  For example, a 1990 study demonstrated that average tooth decay was 61% to 100% higher among school children who grew up in communities with low fluoride levels compared to communities with optimal fluoride levels.

  In 1993-4, an oral health needs assessment of children in California found that children in grades K-3 who were lifetime residents of nonfluoridated communities, and whose family income was below 200% of the Federal Poverty Level, had 39% more decay in their baby teeth compared to counterparts in optimally fluoridated areas.

• Do adults benefit from fluoridation?

  Fluoridation protects against dental decay throughout life. Inadequate exposure to fluoride places both children and adults in the high risk category for dental decay.

  Fluoride benefits adults in two ways. It helps rebuild (remineralize) tooth decay, which can prevent the spread of cavities and by frequent exposure to small amounts of fluoride, even reverse its damage.

  Fluoride also protects adults against root decay. Adults with gumline recession are at risk for root decay because the root surface becomes exposed to decay-causing bacteria in the mouth. Fluoride acts against those bacteria and their effects on exposed tooth surfaces.

• Can the consistent use of bottled water result in missing the benefits of optimally fluoridated water?
  Yes. The majority of bottled waters on the market do not contain optimal levels of (0.7-1.2 ppm) of fluoride.

  The fluoride content of bottled water can vary greatly. In a 1991 study of 39 bottled water samples, 34 had fluoride levels below 0.3 ppm. If the fluoride level is not shown on the label of the bottled water, the company can be contacted, or the water can be tested to obtain this information. The fluoride level should be tested periodically if the source of the bottled water changes and, at a minimum, on a yearly basis.

• Can fluoridated water adversely affect my health?
  Abundant scientific evidence indicates that fluoridation of community water supplies at the recommended levels is both safe and effective. Medical investigations have not shown any impairment of general health as a result of fluoridation.

  For generations millions of people have lived in areas where fluoride is found naturally in drinking water in concentrations as high or higher than those recommended to prevent tooth decay. In addition, a 1993 National Research Council confirmed that the currently allowed fluoride levels in drinking water do not pose a risk for health problems such as cancer, kidney failure, or bone disease.

  Since 1950, when the American Dental Association began its support of water fluoridation, the American Medical Association the World Health Organization, and the U.S. Public Health Service have all reviewed the effectiveness of fluoridation and recommended it as a means of preventing tooth decay.

• What is fluorosis?
  Dental fluorosis causes white spots on the tooth enamel, usually detectable only by a dental professional, that can result when children regularly consume higher-than-recommended amounts of fluoride while their teeth are still forming (ages 8 and younger). Moderate or severe dental fluorosis can cause more extensive enamel change, but is uncommon.
• Is fluoride toothpaste recommended for children?
  Fluoride toothpaste is safe for children, and recommended to help prevent tooth decay. Children should be discouraged from swallowing fluoride toothpaste, however, since this can lead to fluoride overexposure. For this reason, fluoride toothpaste should not be used by children under 2 years old unless recommended by a dentist, and older children should be encouraged not to swallow fluoride toothpaste when they brush their teeth.
• Can community water fluoridation harm the environment?
  Scientific evidence supports the fluoridation of public water supplies as safe for the environment. The concentration of fluoride in the treated water does not reach levels that could harm any plant or animal species.

More Information

• More about water fluoridation CDC