More than a year after Utah banned fluoride in public drinking water, a St. George dentist is pushing back against what he says are misconceptions about the mineral, arguing that decades of research support its role in preventing tooth decay and improving oral health.
Fluoride in drinking water has been a topic of discussion among many American cities, especially since Utah Gov. Spencer Cox signed Fluoride Amendments, known as HB 81, in the 2025 legislative session. The law effectively banned the use of fluoride in the state’s drinking water as of May 7, last year. This decision has sent ripples across the dental scene throughout the Beehive State.
Dr. Richard Denos, a general dentist practicing in St. George, is one of the dentists speaking out against the ban. Denos cited a study conducted by the National Institutes of Health that linked fluoride consumption to lower IQ levels.
“The problem with that was that the study on the first review was not passed; it wasn’t passed on the second review because they didn’t feel the science was very good on it,” Denos said. “On the third review, they finally got it to be published, and it wasn’t because of a governmental agency saying something about this. It was a judge in San Francisco who actually said that there shouldn’t be any more fluoridation until there’s a follow-up study.”
Dental experts like Denos say that fluoride in drinking water can improve residents’ overall dental health. Denos said the trend of adding fluoride to drinking water originated in parts of Texas and New Mexico, where water had higher fluoride levels.
Researchers found that those residents experienced less tooth decay than residents in areas without fluoridated water.
Denos said studies on the negative effects of fluoride in the human body appear every 10 to 15 years, and it does have a negative impact when consumed in large quantities.
“Fluoride is like any other chemical, and in excessive quantities, it’s poison, just like chlorine or anything else,” Denos said. “But in really small quantities, I believe that the thing we’re looking for mainly is about .4 parts to (.7) parts per million. In that low concentration, there’s a lot of significant benefits to it. That study actually went as high as 1.5 parts per million, instead of .4 parts per million, so it’s roughly four times as high. Even if you go to .7, which is the higher end of it, that study was using fluoride concentrations which were twice what the suggested fluoride concentrations would be.”
In an interview with SciLine, Dr. John Robert Warren, a professor of sociology at the University of Minnesota, echoed Denos’ statement on fluoride concentration levels.
“There are also well-established harms if you have extremely high levels of fluoride, but that isn’t relevant for public policy debates because nobody’s talking about putting in massive doses,” Warren said. “There’s also contested evidence about whether fluoride has any meaningful connection to children’s IQ or cognition.”
Warren’s study at the University of Minnesota conflicted with a National Institutes of Health study.
“We found no relationship between fluoride exposure in adolescence from community drinking water and either IQ in the study that came out last week or students’ academic test scores in the study that came out late last year, or in both studies with cognition later in life,” Warren said.
Both Denos and Warren cited other studies that reported similar findings, including those in the Proceedings of the National Academy of Sciences.
Both professionals said fluoride is vital for dental health and that the levels of fluoride in drinking water are far lower than what skeptics worry about.
Original article online at: https://www.stgeorgeutah.com/news/st-george-dentist-pushes-back-on-fluoride-concerns-after-utah-ban/article_f030beaa-7c21-4d2a-830c-86a7cd10fa0b.html