Is fluoride in drinking water safe?
This question has become a popular one during the last year, as states continue to consider legislation that will influence communities across the US. Recently, the Environmental Protection Agency (EPA) announced plans to review public health risks from fluoride in drinking water, keeping the discussion firmly in the spotlight.
Lisa Simon, MD, DMD
Research on the topic has never been more important.
Last year, findings showed ending water fluoridation could result in more than 25 million additional decayed teeth among children in the next five years and an estimated $9.8 billion in added health care costs. And now, a new study, “Community Water Fluoridation and Birth Outcomes,” published in JAMA Network Open, shows that community water fluoridation is not associated with infant health as measured by birth weight.
“Our paper is part of the attempt to prove that fluoride is safe and that its benefits far outweigh the potential for harm,” says Lisa Simon, MD, DMD, coauthor of the study. Dr. Simon was recently appointed to serve as the new director of Harvard School of Dental Medicine’s (HSDM) Initiative to Integrate Oral Health and Medicine. She also serves as an assistant professor of Oral Health Policy and Epidemiology at HSDM, assistant professor of Medicine at HMS, and associate physician at Brigham & Women’s Hospital.
Below, Dr. Simon dives deeper into the reasons she and her coauthors conducted the research and the potential next steps.
What are the key findings of this study?
Our study found that babies born between 1968 and 1988 in counties that added fluoride to public drinking water did not have a lower birth weight than babies born in those same counties before fluoride was added, or in counties that never added fluoride to public drinking water.
What motivated you and your coauthors to undertake this study? Was there a gap in existing research you hoped to address?
There is ample evidence of fluoride’s benefits to teeth, but a few small observational studies have suggested that community water fluoridation could cause neurologic damage. These studies have, unfortunately, had traction in alternative health circles, leading to proposals for fluoride bans, like those that have taken effect in Utah and Florida. Yet, a growing body of work using the best scientific techniques available has not found any evidence of harm from fluoride exposure at typical, safe levels.
Clinicians often field questions from patients about fluoride safety — how do these results influence those conversations?
Based on our study, dentists can tell patients that, using the best evidence available, being exposed to fluoride during gestation does not negatively affect fetal brain development. And we know that fluoride exposure before birth strengthens the already-developing primary teeth!
Does your study tell us anything about fluoride and IQ or neurodevelopment? If not, are there any plans to study those?
While birth weight doesn’t directly tell us about cognitive outcomes, it is one measure of infant development that may be associated with cognition. We also have plans to study this more directly in future work.
What are the next steps for this line of research?
Our next project, funded by CareQuest Institute, will use a similar model to identify whether fluoridated water exposure in childhood has effects on cognitive measures in early and late adulthood.
Why are you personally passionate about this research? Why is community water fluoridation important to you?
Fluoridated water is a public health success that makes me proud to be a dentist, and one of the best tools we have to equitably deliver an oral health benefit to people regardless of whether they can access a dentist or dental supplies. Along with CareQuest Institute’s advocacy, researchers need to play a role in teaching people about the safety and benefits of fluoride and help protect this beautiful piece of public health infrastructure.
Editor’s Note: Visit CareQuest Institute’s Community Water Fluoridation page for more information on the benefits of fluoride.