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Community Water Fluoridation: A Proven Solution

Healthy Teeth for Health Life - Sonoma County

Fluoride is a proven way to prevent tooth decay in children and adults. Treating drinking water with fluoride, “fluoridation,” has been shown to decrease tooth decay. The average number of decayed, missing or filled teeth in 12-year olds went down by two thirds, from 4 teeth in the 1960's to 1.3 in 1988-94, mainly due to fluoridation. Nevertheless policymakers seeking to fluoridate the public water supplies have repeatedly met with the barriers of cost and infrastructure challenges, as well as a group expressing public opposition, often based on misperceptions of the benefits and risks of fluoride.

Frequently Asked Questions

Q: What is fluoride? 

A: Fluoride is a naturally occurring mineral present in drinking water. Fluoride is naturally present in all community water systems to some level, but is usually insufficient to help prevent tooth decay. It was the difference in tooth decay between communities with different levels of fluoride naturally present in the water that lead to the understanding of its benefits.

Q: How does fluoride reduce tooth decay? 

A: When present in water at optimal levels, fluoride has been shown to prevent tooth decay in people of all ages by increasing the resistance of tooth enamel to decay. It is especially important for children as it can strengthen both primary and permanent teeth. A major risk for tooth loss in older adults is cavities, especially root caries which commonly affect the molar teeth. Fluoride has been shown to undo newly formed cavities and prevent root caries in adults.

Q: What is community water fluoridation and why do we fluoridate water? 

A: Community water fluoridation refers to addition of fluoride to a water supply. While all drinking water contains some fluoride, water fluoridation adjusts this naturally occurring fluoride level to the optimum level for preventing tooth decay. The optimum concentration of fluoride in water is 0.7 mg/l. Fluoride does not change the taste, smell, or appearance of the water. It is a safe, effective, and economical way to improve dental health for the entire community. No significant negative health consequences have been identified when fluoride is added at recommended levels.

Q: Do adults, as well as children, benefit from water fluoridation? 

A: Yes, water fluoridation provides dental health benefits for both children and adults.

Q: Is there a difference in effectiveness between naturally occurring fluoridated water and water that has fluoride added to it? 

A: No. The same fluoride ion is present in naturally occurring fluoride and fluoride drinking water additives. Also, fluoride metabolism is not affected by different chemical compounds nor are they affected by whether fluoride is present naturally or artificially.

Q: Do water filters remove fluoride? Will using a home water filtration system take the fluoride out of my homes' water? 

A: Most home point-of-use treatment systems installed at single faucets use activated carbon filtration, which does not remove fluoride. Reverse osmosis point-of-use devices can effectively remove fluoride although the amount may vary given individual circumstances.

Q: Does bottled water contain fluoride?

A: Some bottled waters contain fluoride and some do not. Source waters may be fluoridated community tap water, contain naturally occurring fluoride, or fluoride may be added by the bottler. The U.S. Food and Drug Administration does not require bottlers to list the fluoride content in a bottle of water, but does require fluoride additives to be listed. Contact the manufacturer to ask about the fluoride content of a particular brand of bottled water.

Q: What is enamel fluorosis and when does it occur? 

A: Enamel fluorosis is a hypo mineralization of the enamel surface of the tooth that develops during tooth formation. It may range from barely noticeable white spots to pitting and staining. It can occur only during tooth development. Only children 8 years old and younger are at risk, as this is the time when permanent teeth are developing under the gums. Severe enamel fluorosis can occur when young children consume excess fluoride, from any source, during critical periods of tooth development.

Q: What if my child has been receiving fluoride drops or tablets? 

A: Only children living in non-fluoridated areas should use prescription dietary fluoride supplements between the ages of six months to 16 years of age. When the water is fluoridated, there is no need to continue using fluoride drops or tablets. Please consult with your healthcare provider or dentist before starting or stopping the use of fluoride drops, or other supplements.

Q: Should my family continue brushing with fluoridated toothpaste? 

A: Yes. For most people (children over six years of age, adolescents, and adults) brushing at least twice a day with fluoride toothpaste is recommended. Some simple recommendations are advised to reduce the risk of enamel fluorosis among children aged 6 years and younger:

  • Supervise brushing to discourage swallowing toothpaste.
  • Place only a small pea-size amount of fluoride toothpaste on your child's toothbrush.
  • Seek advice from a dentist or other health care professional before introducing fluoride toothpaste to children less than 2 years of age.

The American Dental Association (ADA) believes the warning label on toothpaste exaggerates the potential for negative health effects from swallowing toothpaste. In 1996, the ADA reviewed studies and concluded that "a child could not absorb enough fluoride from toothpaste to cause a serious problem" and added that fluoride toothpaste has an "excellent safety record."

Q: What are the guidelines for breast-fed infants?

A: Breastfeeding is the most complete form of nutrition for infants. Breast milk has low concentration of fluoride and does not contribute to enamel fluorosis (a defect in the tooth enamel caused by exposure to high concentrations of fluoride during tooth development).

Q: Is it safe to use fluoridated water to mix infant formula?

A: Yes, you can use fluoridated water for preparing infant formula. However, if your child is exclusively consuming infant formula reconstituted with fluoridated water, there may be an increased chance for mild dental fluorosis. To lessen this chance, parents can use low-fluoride bottled water some of the time to mix infant formula; these bottled waters are labeled as de-ionized, purified, demineralized, or distilled.

Q: What is the effect of fluoridation on people with Chronic Kidney Disease (CKD)? 

A: According to the National Kidney Foundation, fluoridation presents no health risks for people with mild renal disease. However, those individuals with end stage renal disease might be at risk for skeletal fluorosis, although there are limited studies addressing this issue. Fluoride concentrations in dialysis machines should follow established guidelines.

Q: Can my pets drink fluoridated water?

A: Yes. Research findings do not support an association between water fluoridation and negative health effects on plants and animals.

Q: What is the effect of water fluoridation on the environment? 

A: Scientists have found a lack of evidence to show an association between water fluoridation and a negative impact on people, plants, or animals.

Q: What is the cost effectiveness of water fluoridation? 

A: The economic analysis found that for larger communities of more than 20,000 people where it costs about 72 cents (in 1999 dollars) per person per year to fluoridate the water, every $1 invested in this preventive measure yields approximately $38 savings in dental treatment costs. In Sonoma County, the average estimated cost of one filling ($146) would provide fluoridation for a family of four over 50 years.

Q: What research has been done on water fluoridation?

A: With over 3,000 studies on fluoridation published, few topics have been as thoroughly researched as water fluoridation. Please see studies published on these websites:

Community Water Fluoridation
Source: The Centers for Disease Control and Prevention.

Fluoridated Water
Source: National Cancer Institute.

Efficacy and Safety of Fluoridation
Source: Australian Government National Health and Medical Research Council.

Supporters of Fluoride

  • Alzheimer's Association
  • American Academy of Family Physicians
  • American Academy of Pediatrics
  • American Association for Community Dental Programs
  • American Association for the Advancement of Science
  • American Cancer Society
  • American Dental Association
  • American Dental Hygienists Association
  • American Dietetic Association
  • American Federation of Labor and Congress of Industrial Organizations
  • American Hospital Association
  • American Medical Association
  • California Dental Association
  • Canadian Medical Association
  • Canadian Nurses Association
  • Consumer Federation of America
  • Hispanic Dental Association
  • Institute of Medicine
  • March of Dimes Birth Defects Foundation
  • National Black Caucus of State Legislators
  • Robert Wood Johnson Foundation
  • American Society for Geriatric Dentistry
  • U.S. Department of Veteran Affairs
  • U.S. Public Health Service
  • Centers for Disease Control and Prevention
  • World Health Organization

Learn More

To learn more about the benefits of community water fluoridation for Sonoma County, please visit: