Community water fluoridation

Evidence Rating  
Evidence rating: Scientifically Supported

Strategies with this rating are most likely to make a difference. These strategies have been tested in many robust studies with consistently positive results.

Disparity Rating  
Disparity rating: Potential to decrease disparities

Strategies with this rating have the potential to decrease or eliminate disparities between subgroups. Rating is suggested by evidence, expert opinion or strategy design.

Health Factors  
Decision Makers
Date last updated

Communities that fluoridate water adjust and monitor fluoride levels in public water supplies to reach optimal fluoride concentrations. Fluoride prevents the demineralization of teeth and enhances tooth enamel1. The U.S. Public Health Service (U.S. PHS) recommends that community drinking water contain .7 ppm of fluoride, down from the previous standard, a range of .7 to 1.2 ppm, set in 1962. This change accounts for other sources of fluoride (e.g., toothpaste) and was intended to avoid the unwanted health effects of excessive fluoride2.

What could this strategy improve?

Expected Benefits

Our evidence rating is based on the likelihood of achieving these outcomes:

  • Reduced cavities

What does the research say about effectiveness?

There is strong evidence that community water fluoridation (CWF) is cost-effective in preventing cavities1, 2, 3, 4, 5 across socio-economic groups1. Effects are strongest in communities with residents with lower incomes6, communities with limited access to oral health care7, and among groups with limited resources to purchase oral health supplies (e.g., toothbrushes, fluoride toothpaste, floss, etc.)8, which are not covered by income support programs such as the Supplemental Nutrition Assistance Program (SNAP)9.

CWF reduces cavities, also known as caries, in children’s baby teeth and permanent teeth4. A systematic review of Brazil-based studies indicates that even with widespread use of fluoride toothpaste, CWF reduces cavities in children under age 1310. High fluoride intake can increase the occurrence of dental fluorosis on children’s teeth, which are mild, white spots that do not impact the function of dental enamel1, 11, 12. Infants who drink formula instead of breast milk may have higher fluoride intake levels and higher occurrence of mild dental fluorosis5. However, the risk of severe dental fluorosis, when pits form in dental enamel, remains low in the U.S.13. Additional research is needed to determine other potential adverse effects of excessive fluoride exposure1, 14.

Recent studies suggest that communities may be more likely to support adding or maintaining fluoride in their water supply as health literacy increases, particularly if neighboring counties have fluoridated water15.

Fluoridation costs an average of 11 cents per person per year in large U.S. communities and under $5 per person per year in very small communities (less than 1000 people), according to data from 2013. Annual cost savings range from $29 to $74 per person in averted dental treatment and productivity losses1, 16.

How could this strategy advance health equity? This strategy is rated potential to decrease disparities: suggested by expert opinion.

Experts suggest community water fluoridation (CWF) has the potential to decrease disparities in cavity rates between children from families with higher incomes and children from families with low incomes. A few descriptive studies suggest CWF may offer the greatest benefit to children from families with low incomes18, 19, 20. Some communities without fluoridation have disparities in cavity rates among children by parental education level and CWF appears to reduce those disparities18, 21. There is little to no research available on the impact of CWF on disparities in cavity rates experienced by children of color18, 21.

The cost of providing care for children with cavities in communities without fluoridated water far exceeds the cost of fluoridating their water. An Alaska-based study of a community that stopped adding fluoride to their water shows a 111% increase in costs six years later to treat cavities for Medicaid-eligible children21. Another analysis found that for every dollar invested in fluoridating New York State water, the state saves about $10 in dental repair services for Medicaid-eligible children22.

What is the relevant historical background?

The practice of fluoridating community water started when Dr. H. Trendley Dean noticed that communities with water sources that were naturally fluoridated experienced less tooth decay than those without naturally fluoridated water23. Grand Rapids, Michigan was the first American city to add fluoride to their water supply in 1945; five years later, children in their city had lower rates of tooth decay than the surrounding communities. Cities and communities across the U.S. quickly adopted the practice. Today, nearly 3 out of 4 Americans are drinking from public water sources with enough fluoride to prevent tooth decay5.

Data from the last half-century show that the implementation of community water fluoridation (CWF) kept pace with U.S. population growth and reduced cavity rates. However, this has changed in the U.S. over the last decade as unsubstantiated claims about CWF have influenced public opinion. Some communities have incorrectly stopped considering cavities as a public health problem and no longer add fluoride to their water supply, despite evidence that cavities are one of the most prevalent chronic diseases that affect communities with low incomes and fewer resources. In some instances, political processes or community members who oppose public health measures can make it difficult to create or maintain CWF policies.24.

Equity Considerations
  • How does your community perceive the benefits of community water fluoridation (CWF)? How does power (i.e., money, knowledge, interpersonal relationships, etc.) shape community perspective?
  • Who experiences poor oral health outcomes (e.g., cavities) in your community? Which strategies, in addition to CWF, can ensure that everyone has the opportunity to practice good oral health?
  • Who may not have access to water treated by CWF policies (e.g., rural areas with private wells)? What are other ways that your community can offer them resources and support to prevent dental diseases?
  • How much trust is there between your community and the municipal water provider? How does the municipal water provider share updates with the community about how they are following federal fluoride recommendations?
Implementation Examples

As of 2018, 73% of Americans (approximately 207 million people) live in communities that fluoridate their water17.

Implementation Resources

Resources with a focus on equity.

CDC-CWF - Centers for Disease Control and Prevention (CDC). Community water fluoridation (CWF).

CDC-CWF Resources - Centers for Disease Control and Prevention (CDC). Community water fluoridation (CWF): Resources for public health partners and professionals.

CDC-MWF Water system - Centers for Disease Control and Prevention (CDC). My water’s fluoride (MWF): Find water system information.

ADA-Fluoridation - American Dental Association (ADA). Mouth Healthy: Fluoridation information.

Pew-CWF - The Pew Charitable Trusts (Pew). Promoting community water fluoridation (CWF). 2015.


* Journal subscription may be required for access.

1 CG-Oral health - The Guide to Community Preventive Services (The Community Guide). Oral health.

2 US PHS-Fluoride - U.S. Department of Health and Human Services (U.S. DHHS) Federal Panel on Community Water Fluoridation. U.S. public health service (U.S. PHS) recommendation for fluoride concentration in drinking water for the prevention of dental caries. Public Health Reports. 2015;130(4):318-331.

3 Truman 2002 - Truman BI, Gooch BF, Sulemana I, et al. Reviews of evidence on interventions to prevent dental caries, oral and pharyngeal cancers, and sports-related craniofacial injuries. American Journal of Preventive Medicine. 2002;23(1 Suppl 1):21-54.

4 Cochrane Iheozor-Ejiofor 2015 - Iheozor-Ejiofor Z, Worthington HV, Walsh T, et al. Water fluoridation for the prevention of dental caries. Cochrane Database of Systematic Reviews. 2015;(6):CD010856.

5 CDC-CWF - Centers for Disease Control and Prevention (CDC). Community water fluoridation (CWF).

6 Burt 2002 - Burt BA. Fluoridation and social equity. Journal of Public Health Dentistry. 2002;62(4):195-200.

7 Pizzo 2007 - Pizzo G, Piscopo MR, Pizzo I, Giuliana G. Community water fluoridation and caries prevention: A critical review. Clinical Oral Investigations. 2007;11(3):189-193.

8 Cochrane-Walsh 2019 - Walsh T, Worthington HV, Glenny AM, Marinho VCC, Jeroncic A. Fluoride toothpastes of different concentrations for preventing dental caries. Cochrane Database of Systematic Reviews. 2019;(3):CD007868.

9 USDA-SNAP buy - U.S. Department of Agriculture (USDA), Food and Nutrition Service (FNS). Supplemental Nutrition Assistance Program (SNAP): What can SNAP buy?

10 Belotti 2022 - Belotti L, Frazão P. Effectiveness of water fluoridation in an upper-middle-income country: A systematic review and meta-analysis. International Journal of Paediatric Dentistry, 2022;32(4):503-513.

11 CDC-CWF-Fluorosis - Centers for Disease Control and Prevention (CDC). Community water fluoridation (CWF) FAQs: Fluorosis.

12 Whelton 2004 - Whelton HP, Ketley CE, McSweeney F, O’Mullane DM. A review of fluorosis in the European Union: Prevalence, risk factors and aesthetic issues. Community Dentistry and Oral Epidemiology. 2004;32(Suppl 1):9–18.

13 Chou 2021 - Chou R, Pappas M, Dana T, Selph S, Hart E, Fu RF, Schwarz E. Screening and Interventions to Prevent Dental Caries in Children Younger Than 5 Years: Updated Evidence Report and Systematic Review for the U.S. Preventive Services Task Force. Journal of the American Medical Association. 2021; 326(21):2179-2192.

14 Peckham 2014 - Peckham S, Awofeso N. Water fluoridation: A critical review of the physiological effects of ingested fluoride as a public health intervention. The Scientific World Journal. 2014;2014:293019

15 Curiel 2020 - Curiel JA, Sanders AE, Slade GD. Emulation of community water fluoridation coverage across U.S. counties. JDR Clinical and Translational Research. 2020;5(4):376-384.

16 CG-Ran 2016 - Ran T, Chattopadhyay SK, Community Preventive Services Task Force. Economic evaluation of community water fluoridation: A Community Guide systematic review. American Journal of Preventive Medicine. 2016.

17 CDC-CWF Data - Centers for Disease Control and Prevention (CDC). Community water fluoridation (CWF). Water fluoridation data & statistics.

18 Matsuo 2020 - Matsuo G, Aida J, Osaka K, Rozier RG. Effects of Community water fluoridation on dental caries disparities in adolescents. International Journal of Environmental Research and Public Health. 2020;17(6).

19 McLaren 2022 - McLaren L, Patterson SK, Faris P, et al. Fluoridation cessation and oral health equity: a 7-year post-cessation study of Grade 2 schoolchildren in Alberta, Canada. Canadian Journal of Public Health. 2022.

20 Sanders 2019 - Sanders AE, Grider WB, Maas WR, Curiel JA, Slade GD. Association between water fluoridation and income-related dental caries of U.S. children and adolescents. Journal of the American Medical Association Pediatrics. 2019;173(3):288-290.

21 Meyer 2018 - Meyer J, Margaritis V, Mendelsohn A. Consequences of community water fluoridation cessation for Medicaid-eligible children and adolescents in Juneau, Alaska. BMC Oral Health. 2018;18(1):1-10.

22 Edelstein 2015 - Edelstein BL, Gary H, Frosh M, Jayanth K. Reducing early childhood caries in a Medicaid population: A systems model analysis. Journal of the American Dental Association. 2015;146(4), 224-232.

23 AADR-Ajiboye 2018 - Ajiboye AS, Dawson DR, Fox CH. American Association for Dental Research policy statement on community water fluoridation. Journal of Dental Research. 2018;97(12):1293-1296.

24 Zokaie 2021 - Zokaie T, Pollick H. Community water fluoridation and the integrity of equitable public health infrastructure. Journal of Public Health Dentistry. 2021.

Related What Works for Health Strategies