With a push from RFK Jr., baseless fears about fluoride go mainstream

Adding fluoride to water is considered one of the great public health achievements of the 20th century. 

With President-elect Donald Trump in the White House, the 21st century may be another story.

Robert F. Kennedy Jr., whom Trump has pledged to let “go wild” on public health under his administration, is an outspoken opponent of adding fluoride to drinking water. He intends to take action.

“I am going to advise the water districts about their legal liability, their legal obligations, their service to their constituents, and I’m going to give them good information on the science and fluoride will disappear,” RFK Jr. told NBC last week.

Scientific evidence shows that fluoridating water is beneficial to dental health and safe at the levels the U.S. currently maintains, according to experts. But the views voiced by RFK Jr. and others show how Americans’ growing distrust of scientific and civic institutions could culminate in rolling back public health tools with proven benefits — in this case, particularly for children who don’t have access to regular dental care. 

“It’s insane,” said Matthew Dallek, a political historian at George Washington University. Rumors about fluoride date back to the 1960s, when the conservative group The John Birch Society suggested it was a “communist plot” and a prime example of government overreach. 

But even then, “there was no groundswell of popular support to remove fluoride from the drinking water,” Dallek said. “What is most frightening is that in the past decade, and especially in the past few months, it has become a live debate.”

A recent Washington Post opinion piece by emergency physician and former Baltimore health commissioner Leana Wen, for example, suggested that removing fluoride is “not an entirely crazy idea.” 

State and local governments regulate water fluoridation and many other public health measures, which limits what the Trump administration could do directly, according to Lawrence Gostin, the director of the O’Neill Institute for National and Global Health Law. But the administration could pressure states to ban fluoride, and conservative state governments may heed those calls.

“RFK Jr. could also put out false or misleading information about the effects of fluoride in the water supply, which would scare the public and do harm,” Gostin said.

The health benefits of water fluoridation

Almost all water has some naturally occurring fluoride in it. “Some [water sources] have very little, some have too much. Some have just the right amount. It’s a Goldilocks story,” says Howard Pollick, who has advised the state of California on fluoridation. 

Researchers first became aware of water fluoridation in the early 20th century when investigating why people in Colorado Springs had discolored teeth. It turned out that Colorado Springs’ fluoride levels were abnormally high. But at lower levels, under 1 milligram for every liter of water, researchers found no fluorosis, or staining of teeth. 

Fluoride also offered dental benefits. When people eat carbohydrates, the carbohydrates mix with saliva to become acids that slowly chip away at teeth. At levels of at least 0.7 milligrams per liter of water, fluoride helps prevent cavities by providing ions to help rebuild the teeth. 

In the mid-20th century, some areas of the U.S. began artificially adding fluoride to water supplies that otherwise had levels that were too low in it to protect against tooth decay. The first city to fluoridate water, Grand Rapids,  Michigan, saw a 60% decrease in the number of kids with cavities after 11 years. Today, about 70% of Americans have fluoride in their water. 

But fluoridation has also spurred controversy. Because of its ubiquity, it’s “kind of a perfect conspiracy theory. Fluoride is invisible. It’s in the drinking water. The government has forced it down your throat, literally and figuratively,” Dallek adds.  

Different unsubstantiated claims have circulated about the potential harms of fluoride, such as claims it is a neurotoxin or that it is associated with cancer. Side effects such as fluorosis and skeletal fluorosis — which weakens bones — are real, but only apply at higher dosages of fluoridation than is allowed in the U.S. 

A common concern cited by anti-fluoridation activists in recent years is a controversial 2019 study linking small decreases in children’s IQ to maternal exposure to fluoridation. But several experts note that the association is not causative and that there were important limitations to the study, such as conducting IQ tests at ages 3 and 4 — before the test is reliable because most children cannot read at that age. 

“There’s not a real mechanism” to explain the association, said John Fawell, a professor at Cranfield University who has advised the World Health Organization on water quality standards. “So one has to be a little cautious about conclusions.” 

There are reasons to further study fluoride to see if these associations are meaningful, he continued, but that may be difficult in a politicized environment. 

“It wouldn’t go amiss to have a closer look again,” he said. “[But] I think that that may not be possible in a sensible way when you’ve got a senior member of the new government making statements like [RFK Jr.] has.” 

Why water fluoridation is a health equity issue

In recent years, some communities have decided to stop fluoridating their water. Calgary, a city in Canada, ceased fluoridation in 2011. But just a decade later, in 2021, Calgary decided to bring it back. A study from earlier this year found more children in Calgary needed dental surgery during the period without water fluoridation compared to children in a nearby town that continued fluoridating water. 

“We had a whole generation who were born from 1991 to 2001 during 20 years of fluoridation,” said Juliet Guichon, a professor of community health science at the University of Calgary who was involved with the push to reintroduce fluoride. “They couldn’t understand why this had to happen to their children or grandchildren.” 

The city of Juneau, Alaska also removed fluoride from drinking water in 2007. Research showed that dental procedures related to cavities increased after Juneau got rid of fluoride — particularly among children in socioeconomically disadvantaged families. 

“I would go as far as to say that community water fluoridation is probably our best health equity-oriented public health intervention that we have,” said Jennifer Meyer, a nurse and professor of health sciences at the University of Alaska, Anchorage who led that study.  

Do we still need fluoridation? 

Thanks to the widespread availability of toothpastes that contain fluoride today, the benefits of fluoridated water are lower. Early campaigns to add fluoride to water decreased rates of tooth decay by around 60%; nowadays, that number is close to 25%. 

“People forget that we need to have fluoridation because many people in power don’t have a big cavity problem,” said Steven Levy, a professor of preventive and community dentistry at the University of Iowa’s College of Dentistry. “Most people in Congress or in the state house don’t appreciate that a substantial portion of the population still has many dental cavity needs because they themselves aren’t having it.” 

While the benefits may not be as great as they once were, water fluoridation is still very cost-effective. Every dollar spent on fluoridation saves around $20 on preventing the need for procedures, the CDC estimates. The Centers for Disease Control and Prevention, the American Medical Association, American Academy of Pediatrics, and the American Dental Association all recommend community fluoridation programs.  

“I’m not aware of anything that would support stopping fluoridation where it’s already in place,” said Anne-Marie Glenny, a professor of health science at the University of Manchester who was an author on a Cochrane review of fluoridation and tooth decay. Without considering programs to replace the fluoride people currently get from water, “it would be foolish to take fluoride out,” she said. 

If Trump and RFK Jr. succeed in using their positions to discourage fluoridation, the public health effects of the switch will only become apparent in the years to come. 

“What always gets me as a nurse is that the people that profit from this kind of misinformation, none of them are at the bedside while that kid is getting a procedure to deal with extensive tooth decay, or an extraction or full mouth reconstruction in the operating room,” Meyer said. “They’re not there to deal with that. But health care, public health, dental professionals are.”