Water Fluoridation: A Proven Solution

Fluoride is a proven way to prevent tooth decay in children and adults. Treating drinking water with fluoride, or "fluoridation" has been shown to decrease tooth decay. The mean 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: Is tooth decay a serious problem in Sonoma County?

A: According to the Sonoma County Smile Survey 2009, about 1 in 6 kindergarteners (16%) and 1 in 6 third graders (17%) had untreated tooth decay. Also, about 2 in 3 Latino kindergartners had tooth decay (65%) as compared to 1 in 3 (32%) of their White counterparts. In fact, Latino children were almost 4 times as likely as white children to need urgent dental treatment. The survey examined the oral health status of children in "Higher Income" schools (where less than 25% of students are eligible for free lunch) as compared to "Lower Income" schools (at least 75% of students eligible for free lunch). Students from lower income schools were more than twice as likely as those from higher income ones to have experienced tooth decay. Approximately 1 in 3 students from "Higher Income" school experienced tooth decay (30.6%) compared with 2 in 3 (67.3%) of students in "Lower Income" schools.

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. It is especially important for children, for whom it makes the teeth more resistant to decay. A major risk for tooth loss in older adults is cavities, especially root caries. Root caries most 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. Some water is bottled directly from fluoridated community tap water and resold to consumers. Fluoride can occur naturally in source waters used for bottling or be added. 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.

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: Which health organizations support and endorse water fluoridation?

A: American Dental Association (ADA)
California Dental Association (CDA)
Centers for Disease Control and Prevention (CDC)
American Medical Association (AMA)
American Academy of Pediatrics (AAP)
U.S. Surgeon General
National Institute of Dental & Craniofacial Research (NIDCR)
World Health organization (WHO)

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: How can I learn more about water fluoridation?

A: Visit these websites:

Centers for Disease Control and Prevention

American Dental Association

Fluoridation Science: Frequently Asked Questions

Where does fluoride come from?

Fluoride is extracted from phosphate rock, and so is phosphoric acid-an ingredient in Coke and Pepsi. Neither one of them comes from fertilizer.

Fluoride is extracted from the same phosphate rock that is later used to create fertilizers that will enrich soil. This is accomplished through an efficient process, and opponents are wrong to suggest that fluoride "comes from fertilizer."

Is water fluoridation safe?

The quality and safety of fluoride additives are ensured by Standard 60, a program commissioned by the Environmental Protection Agency (EPA). Standard 60 is a set of standards created and monitored by an independent committee of health experts. This committee provides regular reports to the EPA. More than 80 percent of fluoride additives are produced by U.S. companies, but no matter where they come from, Standard 60 uses on-site inspections and even surprise "spot checks" to confirm the additives meet quality and safety standards.

Is fluoridated water safe to drink, even in large quantities?

The Institute of Medicine's Recommended Daily Allowance for adult males is 4.0 milligrams.

Community water fluoridation concentration averages 0.9 milligram/Liter. If you drink 2 quarts (1.9 Liter) of water in a day, that amounts to 1.71 milligrams of fluoride each day.

The maximum level of daily nutrient intake that is likely to pose no risk of adverse effects is 10.0 milligrams. In order to reach the maximum daily intake an adult male would need to consume nearly 12 quarts of fluoridated water. That's 600 percent the recommended intake of water each day.

Are additives to the water considered "pharmaceutical" quality?

Additives used in water fluoridation meet standards of the American Water Works Association and National Sanitation Foundation, International and are tested for purity. Chlorine is added to drinking water using the same standards.

Are there issues of civil liberty?

Filters are available to de-fluoridate water, if that is a personal choice. Or distilled water can be consumed instead. Fluoride is not a medication. It is a mineral, and when present at the right level, fluoride in drinking water has two beneficial effects: preventing tooth decay and contributing to healthy bones.

U.S. court decisions have rejected the argument that fluoride is a "medication" that should not be allowed in water. The American Journal of Public Health summarized one of these rulings, noting that "fluoride is not a medication, but rather a nutrient found naturally in some areas but deficient in others."

Participation in civil society involves numerous examples where public policies are initiated for common good. The law requiring helmets by motorcyclists and bicyclists "infringes on personal freedom" to protect society from the burden of caring for an injured individual.

There are several examples of how everyday products are fortified to enhance the health of Americans - iodine is added to salt, folic acid is added to breads and cereals, and Vitamin D is added to milk.

Is fluoride safe for human health?

Cancer: Scientists at National Cancer Institute evaluated the relationship between the fluoridation of drinking water and the number of deaths due to cancer in the United States during a 36-year period, and the relationship between water fluoridation and number of new cases of cancer during a 15-year period. After examining more than 2.2 million cancer death records and 125,000 cancer case records in counties using fluoridated water, the researchers found no indication of increased cancer risk associated with fluoridated drinking water.

Thyroid: Four separate studies have been conducted to evaluate the effect of the amount of fluoride in community water fluoridation on the thyroid gland. The studies found no association between optimal levels of fluoride in drinking water and thyroid cancer, nor hypothyroidism.

Pineal Gland: One small study of 11 cadavers, whose average age at death was 82 years old. The pineal gland of older individuals calcifies as part of the normal aging process. Fluoride was found in the pineal gland, as would be expected given that 99% of fluoride present in the body is associated with hard or calcified tissues. The study concluded fluoride levels were not indicators of long-term fluoride exposure.

Many other studies on specific target organs and disease have been conducted. Please visit the websites listed below for more information.

If I use fluoride toothpaste, will I get too much fluoride from water fluoridation?

Every single day, millions of Americans use fluoride toothpaste without any negative effect whatsoever. This warning label simply reflects two facts:

  • The fluoride concentration in toothpaste is roughly 1,000 times higher than that of fluoridated water.
  • Young children's use of toothpaste should be supervised by a parent.

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."

What research has been done on water fluoridation?

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.

Fluoride Science
Source: The Center for Fluoride Research Analysis.

Fluoridated Water
Source: National Cancer Institute.

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

Children and Tooth Decay

Most Sonoma County children do not have access to fluoridated drinking water. As a consequence they are suffering high rates of preventable tooth decay. Fluoridated drinking water has proven to be the most effective public health measure for prevention of tooth decay. Though most Americans, 72%, receive fluoride through the public water supply, the vast majority of Sonoma County residents do not: only 3% of the public water supply in Sonoma County is fluoridated. Among the cities, only Healdsburg fluoridates its water. Those living outside the cities may draw their drinking water from private wells and usually do not fluoridate the water they draw. 

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 Hygientists' 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:

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