Even before Robert F. Kennedy Jr. took office as health secretary, he promised to take action on water fluoridation. He would provide “good information” to municipalities, which regulate the water supply, and “fluoride will disappear,” he said in November.
In just over a couple of months, some places have made this a reality. Utahand Florida have both banned the addition of fluoride in water, with advocates of the laws like Kennedy arguing that adding the mineral to water poses a risk to children’s developing brains.
A new study tried to predict the consequences if the rest of the nation were to follow suit. In five years, the researchers estimated, 7.5% more U.S. children ages 0-19 would get cavities, affecting 25.4 million additional teeth and costing the country around $9.8 billion. While these findings are worrisome, several experts said, they were unsure if the new data would move the needle on a debate that has become so heated and politicized.
“I think this is very important, because it really helps us sort out what the course of action would be if communities choose to stop fluoridation, and it informs the calculation of the impact,” said Mark Moss, a dental epidemiologist at East Carolina University, who was not involved with the study. “We know a lot about the benefits of fluoride, and this paper really brings that home.”
Fluoride has been artificially added to water in the United States for decades, after dentists discovered that people living in towns with higher levels of naturally occurring fluoride had fewer cavities. It was considered one of the greatest public health achievements of the 20th century. But it has not been without controversy. In the 1960s, the John Birch Society, a conservative advocacy group, promoted the idea that fluoridation was part of a Communist plot.
More recently, there has been growing concern in some communities that fluoride could be negatively impacting the IQ of children — an idea that became much more prominent because it was promoted by Kennedy.
The authors of the new study began their project after noticing more and more attention surrounding fluoridation.
“I think fluoride is an amazing public health success. I think it’s something that we know works. We’ve seen huge, dramatic decreases, not only in the amount of dental disease that children have, but you know, it’s been since 1945, we now have a population of older adults that have more teeth than any other generation in history,” said Lisa Simon, a health services researcher, dentist, and internist at Brigham and Women’s Hospital, who was an author of the study. “I understand that people are nervous about the idea of something being added to their water that they can’t control, and it’s important to study it, but we have, and we know that what it does is not only increase the oral health for everybody and provide for the vast majority of Americans a lot of benefit, but especially benefits Americans who can’t get to a dentist or don’t have access to preventive care.”
The study used a nationally representative dataset of children to predict what would happen if the public water supply were to no longer be fluoridated. The model incorporated the level of fluoride in the water supply as a proxy for how much fluoride the children are exposed to — then predicted the increase in cavities that would come about because of the loss of that fluoride.
Outside experts said the author’s cost estimate could be conservative, because it doesn’t account for all of the costs associated with ceasing fluoridation. Parents would have to take off work to go to the dentist, children with severe tooth decay would have to have more intensive surgeries and emergency room visits for pain that results from cavities, and a larger dental workforce would have to be trained to deal with the influx of cavities.
“We already struggle trying to provide care to people who are on Medicaid or who don’t have insurance, and to increase the burden in those populations, the system’s going to implode. I mean, we just don’t have the capacity to manage that,” Moss said.
The study did not include the potential effects on IQ that have garnered concern, because much of the literature suggests that at the levels most children are exposed to fluoride in the U.S., there are no effects on IQ. But, should those concerns be borne out in future research, that could also have massive economic implications, said Bruce Lanphear, a medical epidemiologist at Simon Fraser University who has done work on fluoride and IQ in Canada.
He questioned the study’s use of levels of fluoride in the water as a proxy for fluoride exposure, given that children can have other exposures. In his studies, he has used urine tests, which other researchers have pointed out may be flawed.
“If we use only water fluoride, we are picking up a major, probably the major, source, but we’re still missing other important sources, and so while both of them can be meaningful, water fluoride and urinary fluoride, if you want to understand total exposure, you’ve got to use urinary fluoride,” he said.
Part of the justification for removing fluoride from water was to allow for individuals to choose how much fluoride they are exposed to. But even alternatives to fluoridated water have come under attack by politicians in recent weeks.
The Texas attorney general opened up an investigation into companies that make fluoridated toothpaste. The FDA took action to remove fluoride tablets, a common alternative in areas without fluoridated water, from the market.
“It was just embarrassingly weak evidence. I can’t believe that the U.S. Food and Drug Administration, with a straight face, put that out to the public,” said Scott Tomar, a dentist and epidemiologist who has also studied the economic benefits of fluoride.
Across the board, experts lamented that the debate on fluoride has strayed from focusing on science or evidence.
When asked if the new study would affect HHS’s guidance around fluoride, an agency spokesperson responded, “Fluoride is the only chemical added to drinking water that does not treat the water. … The CDC now concedes that fluoride’s predominant benefit to teeth comes from topical contact with the outside of the teeth, not from ingestion. There is no need, therefore, to ingest fluoride.” The spokesperson also referred to a 2024 monograph and 2025 meta-analysis by the National Toxicology Program, which found a potential link between fluoridation and IQ. “That said, HHS is directing the CDC to reconvene the Community Preventative Services Task Force to study and make a new recommendation on fluoride.”
Lanphear said it is high time for the National Academies to reassess the benefits and potential risks of fluoride. But that may be difficult to do. The body, which advises the government on health and science related issues, has experienced layoffs in recent weeks because government contract cuts led to budget shortfalls.
“I don’t know that it could be done that thoughtfully in this political climate, given who would probably be the one convening that,” he said. ”This would probably happen under Kennedy’s watch.”
Original article online at: https://www.statnews.com/2025/05/30/fluoride-drinking-water-ban-could-lead-to-25-million-cavities-cost-billions-new-study-says/