Facts about Fluoride / Fluoridation

What is fluoride?

Fluoride is a form of the chemical fluorine, the thirteenth most common element on Earth. Fluoride can be found naturally in water and soil, and it can also be synthesized in a laboratory where it can be used for industrial products or as an additive in drinking water or toothpaste.c Studies show that fluoride can protect teeth from demineralization caused by corrosive bacterial acid. Fluoride can also strengthen or “remineralize” enamel that has already been damaged.b

Why do many cities fluoridate tap water?

In the 1930s and 40s, scientists discovered that cities with naturally occurring fluoride in their water had fewer cases of dental decay, and where fluoride levels were low, there were higher levels of dental caries.f After years of testing the effects of fluoridated water on the rate of dental decay in communities, fluoridation became the official policy of the U.S. Public Health Service in 1951. Currently, more than 140 million Americans live in fluoridated cities.a

Is fluoride dangerous to drink?

While some opponents of fluoridation have raised concerns over its safety and efficacy, the majority of scientific research, including research conducted by the World Health Organization, supports fluoride as a safe and effective way to prevent dental decay at the recommended level of 1 ppm.b Experts suggest, however, that children who are overexposed to fluoride may develop dental fluorosis, which is a discoloration or mottling of teeth. The CDC recommends that low-fluoridated water be used to prepare baby formula to lessen the risk of dental fluorosis.d

Does a carbon filter remove fluoride from drinking water?

A solid block carbon filter will take out about 60% of fluoride because carbon filters are capable of removing only two out of the three fluorine isotopes in water. A 60% removal rate is usually adequate for any health issues with excess fluoride.

Does fluoride help prevent tooth decay?

Scientists agree that fluoride helps prevent tooth decay in two ways. First, when fluoride is ingested, it is absorbed by the teeth and bones, which can strengthen existing bone structure. Second, fluoride helps prevent dental caries topically through the application of toothpaste, gel, or a rinse.b Systemic and topical fluoride can be used together to help prevent tooth decay. Parents of children under the age of 7 should supervise children’s brushing and use only a pea-sized amount or a smear of fluoride toothpaste.e

Does fluoride need to be swallowed to prevent tooth decay?

While recent studies suggest that swallowing fluoride may not affect teeth that have not yet erupted, fluoridated water is estimated to reduce tooth decay by 18-40% in children and 35% in adults. While these numbers point to the continued importance of systemic fluoride, ingested fluoride’s effect has become less than it has been in the past due to improved hygiene and the widespread use of fluoride toothpaste.b Of course, fluoride alone will not completely prevent tooth decay. Brushing, flossing, good nutrition, and seeing a dentist regularly are all critical in maintaining healthy teeth.a

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  • a Cheng, K.K., et al. 2007. “Adding fluoride to water supplies.” British Medical Journal 335 (7622): 699-702.
  • b Fawell, J., et al. (World Health Organization) 2006. Fluoride in Drinking-water. IWA Publishing: London, England. Accessed: June 21, 2010.
  • c Groves, Barry. 2001. Fluoride: Drinking Ourselves to Death? Dublin, Ireland: Newleaf.
  • d “Interim Guidance on Reconstituted Infant Formula.” American Dental Association. November 9, 2006. Accessed; June 21, 2010.
  • e Kahuna Kupua A’o, Lono. 1998. Don’t Drink the Water. Pagosa Springs, CO: Kali Press.
  • f Roosevelt/Bellingham, Margot. “Health: Not My Water Supply.” Time. October 17, 2005. Accessed: June 7, 2010.