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Fluoride and Fluoridation

Fluoride is one of the world's most studied substances. Thousands of studies have been conducted over the past 70 years to establish and confirm fluoride's benefits: Fluoride is safe. Fluoride is inexpensive. Fluoride benefits everyone—regardless of age and socioeconomic status.

What Is Fluoride?

Fluoride is a naturally-occurring mineral found in water sources across the globe. When swallowed or applied to the teeth, fluoride helps prevent cavities in children and adults by making the outer surface of teeth more resistant to the acid attacks that cause tooth decay.

According to the American Dental Association, tooth decay is effectively prevented by a combination of both systemic fluoride and topical fluoride applications.

Systemic Fluoride

As children, before teeth break through the gums, the fluoride taken in from foods, beverages, and supplements makes tooth enamel (the hard surface of the tooth) stronger. In addition, the fluoride you take in from foods and beverages continues to provide a topical benefit because it becomes part of your saliva, constantly bathing the teeth with tiny amounts of fluoride that help rebuild weakened tooth enamel.

  • Public drinking water: Cities and towns that have community-fluoridated water adjust the level of existing, naturally-occurring fluoride in their public drinking water to an optimal level for oral health.
  • Fluoride supplements: Fluoride tablets or drops are available by prescription for those who do not have fluoridated drinking water.

Topical Fluoride

When applied to the surface of teeth, the fluoride in toothpaste and other dental products helps rebuild weakened tooth enamel and reverses early signs of tooth decay.

  • Fluoridated toothpastes & mouthwashes
  • Prescription-strength products: These may be prescribed for people who are at a higher risk of decay, like those with a previous history of tooth decay or certain medical conditions, such as dry mouth.
  • Fluoride varnish: A gel is “painted” directly onto the tooth surface. It may be applied at a dental or medical visit.


Community Water Fluoridation


Fluoride water fountain
Fluoridated water is one of the most efficient and effective ways to deliver fluoride. In fact, the U.S. Centers for Disease Control and Prevention (CDC) has named fluoridating community water one of the 10 greatest public health achievements of the 20th century

More than 100 leading health organizations, including the American Dental Association (ADA), Massachusetts Dental Society, American Academy of Pediatric Dentistry, American Medical Association, World Health Organization, and American Cancer Society, recognize the public health benefits of community water fluoridation for preventing dental decay.

What Is Community Water Fluoridation?

Community water fluoridation (CWF) is the adjustment of sub-optimally fluoridated water levels up to the levels recommended for optimal dental health. The U.S. Department of Health and Human Services (HHS) recommends the optimal fluoride concentration level of 0.7 parts per million (ppm).

One milligram per liter (mg/L) of fluoride in water equals one part per million (ppm). One ppm of fluoride is diluted in a million parts of water. The following comparisons give an idea of the amount of one part per million: 1 inch in 16 miles; 1 minute in 2 years; 1 cent in $10,000.

At this concentration level, dental decay is effectively reduced while minimizing the risks of dental fluorosis. The optimal level for a location depends on the annual average maximum daily air temperature of the geographic area.

There are three types of additive options approved by the American Water Works Association and NSF International: sodium fluoride, sodium fluorosilicate, and fluorosilic acid. The benefits of community water fluoridation are the same regardless of the source.

What Should You Do If You Live in a Non-Fluoridated Community?

Children in non-fluoridated areas should have an oral health risk assessment to determine the need for topical treatments and/or systemic fluoride supplements. Supplements may be offered to high-risk children who do not have access to systemic fluoride through age 16. Fluoride varnish should be offered to moderate and high-risk children by a dentist or physician at least twice a year.

Additional Fluoride Resources