Community Water Fluoridation is Effective at Preventing Cavities

CHICAGO, October 4, 2024 — The American Dental Association (ADA) is aware of a recent review released from the Cochrane Library about water fluoridation’s impact on the prevention of tooth decay. The ADA, along with other major health organizations such as the American Academy of Pediatrics and the U.S. Centers for Disease Control and Prevention, continue to endorse community water fluoridation at optimal levels to help prevent tooth decay. The ADA believes the review does not present any new or significant findings on the subject.

“Optimally fluoridated water is accessible to communities regardless of socioeconomic status, education or other social variables,” said Linda J. Edgar, D.D.S., president of the American Dental Association. “Even in an era with widespread availability of fluoride from various sources, other studies show that community water fluoridation prevents at least 25% of tooth decay in children and adults throughout their life span. The scientific weight of sound evidence around the benefit of community water fluoridation is clear and compelling.” 

According to the U.S. Centers for Disease Control and Prevention, water fluoridation and fluoride toothpaste work together to help prevent tooth decay and offer more protection against decay than using either one alone. Fluoridated water keeps a low level of fluoride in the mouth throughout the day, while fluoride toothpaste delivers higher concentrations at important times of the day, such as bedtime .¹

The National Fluoridation Advisory Committee (NFAC), an expert committee of the ADA, examined the review and noted important limitations in the criteria the investigators used for the inclusion of studies and omission of significant findings. It should be noted that a co-author of the study, Dr. Anne-Marie Glenny, was quoted as saying, “There’s no evidence to suggest that where water fluoridation programs are in place, that they should necessarily be stopped...Contemporary studies are showing that water fluoridation is beneficial.”

The ADA is aware of many other recent studies excluded from the Cochrane review that show negative impacts on public health once fluoride is removed from the water supply.

“The study’s exclusion criteria means that highly relevant research from over the past decade that show significant increases in tooth decay in communities like Juneau, Alaska, Calgary, Canada and other countries after their decision to remove fluoride from water supplies were not included” says NFAC member Catherine Hayes, D.M.D., SM, DMSc.

The NFAC also notes that the review did not rely on enough high-quality studies. NFAC suggested the authors must emphasize caution in interpreting results based on the very small number of recent studies.

“Normally, meta-analyses and systematic reviews are only conducted with substantial numbers of relevant high-quality studies,” Dr. Hayes states. “However, there were only a small number of recent studies on which the conclusions are based only two for primary caries [cavities in baby teeth] outcomes and maybe a few more for permanent caries [cavities in adult teeth],” says Dr. Hayes.  

“The analysts at Cochrane also excluded reliable studies because of the year of data collection rather than the quality and reliability of the data. This is an important oversight that cannot be ignored. In addition, Cochrane researchers noted a significant cost-savings due to fluoridation, and this was also not included in the summary,” said Dr. Hayes.

The review advises, “the implementation or cessation of CWF [community water fluoridation] requires careful consideration of this current evidence, in the broader context of a population’s oral health, diet and consumption of tap water, movement or migration, and the availability and uptake of other caries (cavity) prevention strategies.”

“We welcome new research and must always carefully examine the evidence-based scientific methodology of each study and question whether or not the review is complete and impartial in conducting the overall analysis with similar outcomes (e.g. cavities prevention) measured consistently across the globe,” said Dr. Hayes. 

To learn more about the benefits of fluoride, please visit MouthHealthy.org or view Fluoridation Facts on the ADA website.

¹ https://www.cdc.gov/fluoridation/faq/index.html

About the American Dental Association
The not-for-profit ADA is the nation's largest dental association, representing 159,000 dentist members. The premier source of oral health information, the ADA has advocated for the public's health and promoted the art and science of dentistry since 1859. The ADA's state-of-the-art research facilities develop and test dental products and materials that have advanced the practice of dentistry and made the patient experience more positive. The ADA Seal of Acceptance has long been a valuable and respected guide to consumer dental care products. The Journal of the American Dental Association (JADA), published monthly, is the ADA's flagship publication and the best-read scientific journal in dentistry. For more information about the ADA, visit ADA.org. For more information on oral health, including prevention, care and treatment of dental disease, visit the ADA's consumer website MouthHealthy.org.