With Utah’s first-in-the-nation ban on fluoride in public drinking water set to take effect Wednesday, dentists who treat children and low-income patients say they’re bracing for an increase in tooth decay among the state’s most vulnerable people.

Republican Gov. Spencer Cox signed the law against the recommendation of many dentists and national health experts who warn removing fluoride will harm tooth development, especially in young patients without regular access to dental care.

The bill’s sponsor, Republican Rep. Stephanie Gricius, said she does not dispute that fluoride can have some benefits but thinks people should not be given it by the government without their informed consent.

U.S. Health Secretary Robert F. Kennedy Jr. applauded Utah for being the first state to enact a ban and said he plans to direct the Centers for Disease Control and Prevention to stop recommending fluoridation nationwide.

Florida could soon become the second state to ban fluoride under a bill awaiting Republican Gov. Ron DeSantis’ signature. The Ohio and South Carolina legislatures are considering similar measures.

Many patients not in the know

A majority of Utah water systems already did not add fluoride. The state ranked 44th in the nation for the percentage of residents receiving fluoridated water, with about 2 in 5 receiving it in 2022, according to CDC data. The law will impact about 1.6 million people in Salt Lake City and elsewhere in northern Utah who are losing fluoridation, state officials say.

Dentists in Salt Lake City over the past week said many patients were unaware of the upcoming ban, and most did not realize the city had been adding fluoride to their drinking water for nearly two decades.

“I did not know about a ban,” said Noe Figueroa, a patient at Salt Lake Donated Dental Services, a clinic that provides free or heavily discounted dental treatment to low-income residents. “Well, that’s not good. I don’t think that’s good at all.”

At Donated Dental, providers expect their monthslong waitlist for children’s procedures to grow significantly and their need for volunteer dentists to skyrocket. The effects of the ban in children’s teeth will likely be visible within the next year, said Sasha Harvey, the clinic’s executive director.

“Right now, we’re scheduling into August and September for some 2-, 3-, 4-year-olds that are in so much pain that they can’t eat properly, and there’s nothing we can do but tell parents, ‘You’re gonna have to wait.’ It’s heartbreaking,” Harvey said, adding that it’s likely to get much worse.

A public health achievement under scrutiny

The fluoridation process involves supplementing the low levels of naturally occurring fluoride in most water to reach the 0.7 milligrams per liter recommended by the CDC for cavity prevention. Water treatment plants dump fluoride into the water in liquid or powder form and often use dosing pumps to adjust the levels.

Nearly two-thirds of the U.S. population receives fluoridated drinking water, according to health officials. It was long considered among the greatest public health achievements of the last century.

Fluoride fortifies teeth and reduces cavities by replacing minerals lost during normal wear and tear, according to the CDC. It’s especially important to children whose teeth are still developing. For some low-income families, public drinking water containing fluoride may be their only source of preventative dental care.

Some supporters of the Utah law pointed to studies linking high levels of fluoride exposure to illness and low IQ in kids. The National Institutes of Health says it’s “virtually impossible” to get a toxic dose from fluoride added to water or toothpaste at standard levels.

The governor said that, like many people in Utah, he grew up and raised his children in a community without fluoridated water. Before signing the bill, Cox said there is no difference in health outcomes between communities with and without fluoride—a statement Utah dentists say is false.

“Any dentist can look in someone’s mouth in Utah and tell exactly where they grew up. Did you grow up in a fluoridated area or a non-fluoridated area? We can tell by the level of decay,” said Dr. James Bekker, a pediatric dentist at the University of Utah in Salt Lake City.

Barriers to fluoride supplements

The law shifts responsibility to individuals, meaning all Utah residents will need to be proactive about their oral health, Harvey said. Most patients at her clinic only come in when a toothache becomes unbearable, and many cannot spare the few dollars a month needed to buy fluoride supplements to add to their drinking water at home.

Figueroa, the free dental clinic patient, said other expenses take priority.

Fluoride toothpaste alone is insufficient for children because it doesn’t penetrate the tooth’s outer layer, Bekker said. When a person regularly ingests fluoridated water, their saliva bathes the teeth in fluoride throughout the day and makes them stronger.

Bekker said he recommends Utah parents add fluoride supplements to their children’s drinking water. But for families who don’t visit doctors regularly, that may prove difficult.

Fluoride tablets require a prescription from a doctor or dentist. Utah providers are working to make the supplement accessible over the counter, but Bekker said that change may be months or years away.

© 2025 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed without permission.