Utah has just become the first U.S. state to ban fluoride from municipal drinking water. Other states will likely follow. It’s a confusing move by a seemingly even-keeled governor to take an evidence-backed public good (fluoride prevents tooth decay) and turn it into something profit-oriented under the guise of personal freedom. In making the decision, he said, “we ran this natural experiment,” comparing people who had grown up with fluoride in the water and people who hadn’t. He said there wasn’t much of a difference, that he’d talked to dentists, and decided to sign the bill.
I asked the governor’s office for more information about the experiment. I asked the state health department if they had any data from such an experiment. The health department told me, “DHHS does not have data about correlations between water fluoride levels and cavities.” The governor’s office did not respond to my requests.
Can Utah be so different from the rest of the country, from the experiments that show a benefit and the dentists who back fluoridated water? There are roughly one million children in Utah, making it the state with the highest percentage of youth in the nation. This decision is going to land hardest on them.
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To unpack the folly of this law, we only need to look to Hawaii. The cities and towns of Hawaii do not add fluoride to their water supplies even though the state hasn’t banned it. Unless you are on a military base, where the drinking water is fluoridated, residents of Hawaii consume only the low levels of fluoride naturally in the water. From May of 2014 through May 2015, 70 percent of third graders in Hawaii had tooth decay. The national average at the time was 52 percent. It’s unclear if there are more recent data; a spokesperson for the state health department said he would look into it.
What’s amazing is that the health department, in its list of ways it offers parents to prevent tooth decay , says in one report, without irony, “drinking fluoridated water.”
What fluoride does is help strengthen our teeth, which are constantly under assault from bacteria in our mouths; these bacteria take in sugar molecules from food and spit out corrosive acid as a waste product that dissolves our teeth. Fluoride stops this corrosion in several ways. It sticks to the crystals that make up enamel, making it harder for acid to dissolve it. The mineral binds to calcium inside the tiny holes caused by bacterial acid, helping to fill them; this makes teeth just a bit more resistant to acid. And it helps strengthen teeth by attracting more calcium to the surface, creating a mineral shield with enamel that is a bit stronger than what we already have.
Governor Spencer Cox’s decision in Utah comes at a time when the head of U.S. Health and Human Services, Robert F. Kennedy, Jr., wants to remove fluoride from water supplies part of his plan to, in the words of President Donald Trump, “go wild” on health. But the only thing that is wild here is how badly the science supporting fluoridation is being distorted or ignored. Even some of Utah’s dentists, who, you could argue, stand to benefit financially from more children needing fillings, think what Cox has done is hasty.
The state’s own data make it clear what’s at stake.
In 2015, 66 percent of children in the state between the ages of six and nine had at least one cavity. That number will surely increase as now even the 44 percent of Utah residents who were supplied with fluoridated drinking water will no longer have access to it. State health department officials said that they are analyzing the latest data, from 2023, but warned that not very many people participated in their surveys. This is troubling because Cox said in signing the bill that “It’s got to be a really high bar for me if we’re going to require people to be medicated by their government.” That bar has to include all the evidence that exists around the safety and efficacy of fluoride in dental health, not just the word of a few dentists and a nebulous “natural experiment.”
For sure, there are other ways than drinking water to get fluoride. But those ways aren’t as simple as turning on a faucet, especially for people with restricted incomes. Fluoride toothpaste helps. Fluoride varnish that a dentist can apply helps. Buying fluoridated water helps.
But in Utah, state records show there are about 1.1 million dental insurance policies, whether commercial or Medicaid/CHIP, that provide dental coverage for lower income children. While many policies cover fluoride varnish for kids, this option is certainly not easier for working families than walking into the kitchen and filling a cup with fluoridated water. As in the rest of the nation, not every dentist in Utah will accept Medicaid/CHIP. And 66 percent of counties in the state report a shortage of dentists. Being able to buy bottled water is a luxury not everyone can afford.
So, in Utah, as municipalities now have to figure out how to get fluoride out of the water supply, this new law is just as much an economic issue as a health issue. People in the state already spent $52 million in an average year on adult visits to the emergency department related to dental or oral health issues, between 2007 and 2017. In that same period, people spent $4.7 million on pediatric visits to the emergency room, despite insurance. The number of visits related to tooth decay or infection will certainly grow.
Public health measures like fluoride in drinking water are, in essence, great equalizers. Everyone has access to them. Everyone benefits from them. One of the things Cox has done with this law is set the stage for further health disparity in the state. And what’s equally disturbing is that the decision endorses a movement that cherry-picks data and misunderstands the nature of scientific research and the nature of risk.
Resting on a federal study that my colleagues at Scientific American report has twice failed peer review, in 2024, the antifluoride movement convinced a judge in Northern California to rule that the Environmental Protection Agency needed to lower its limit of fluoride in drinking water. The argument was based on the study’s finding that at levels above what HHS currently recommends for drinking water (0.7 milligram per liter), fluoride could affect children’s IQs. Even so, that study has been misinterpreted to build this legal challenge to fluoride. That finding about high fluoride levels? It has nothing to do with adding fluoride to water supplies. The water in question—with levels of fluoride twice what HHS recommends—contains naturally occurring fluoride.
In addition, throughout the review process, scientists pointed out concerns over the way the study was carried out, the international, nonstandardized information that the researchers used to establish the IQ link, and that the study didn’t consider benefits of fluoride or whether their findings were really relevant to the amount of fluoride most U.S. municipal systems have.
For sure, high levels of fluoride can cause health issues. And if you conduct a poorly designed, poorly controlled research study, you can find the harmful link you are looking for. But to say that because some researchers find a detriment, even if many others, countless others, over the decades have found more benefits, then no one can have those benefits, is not upholding personal freedom. It’s making something that is accessible and beneficial to many people less so.
That the pendulum has swung again to claims of personal freedom over real public benefit in the case of fluoride fundamentally misunderstands the role of community and society. No win for personal freedom is consequence-free. Taking something away from people, under the guise of giving them a choice whether to use it, effectively undermines choice. And once again, children pay the price with their dental health, and taxpayers pay the price in helping cover the cost of something we know in great detail how to prevent—tooth decay.
This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.
