A new study published in Jama Health Forum estimates that if the US were to remove fluoride from public drinking water supplies – as Donald Trump’s health secretary Robert F Kennedy Jr has advocated – American children would suffer an additional 25.4m cavities in five years.
The additional cases represent a 7.5% increase in cavities, an added cost of $9.8bn and the loss of 2.9m quality-adjusted life years. Those cases would disproportionately be borne by children most at-risk for tooth decay – those on public health insurance or who lack insurance entirely.
“We know fluoride is remarkably effective at preventing tooth decay – it’s one of the great public health success stories of the 20th century,” said Dr Lisa Simon, assistant professor at Brigham and Women’s Hospital and Harvard Medical School, and a dentist and an internist.
However, she added, the US did not “have great numbers to say: ‘What is the value of all of that? What would happen if we were to take it all away?’”
The study comes as Kennedy has made the end of water fluoridation a major policy of his time as the president’s health secretary. Fluoride was most recently featured in the “Maha report”, led by Kennedy and published amid fanfare by the White House last week. The report was later found to have invented citations and mischaracterized research.
Although the Maha report correctly characterized a recent metaanalysis on the dangers of high levels of fluoride, it downplayed fluoride’s protective effects and did not comment further on cavities – a chronic condition that affects almost half of American kids.
The new study finds that if fluoride were eliminated from water supplies, there would be “one newly decayed tooth for every third child in America”, Simon said.
To conduct the new study, Simon and her coauthor, Harvard assistant professor of oral health and epidemiology Sung Choi, used nationally representative data from the US National Health and Nutrition Examination Survey (NHANES). They then used a statistical model to estimate the cost and prevalence of tooth decay in children aged 0-19-years-old after both five and 10 years. The data examined was from 2013-16 and the analysis was conducted between November and February this year.
Kennedy argues the US should stop fluoridating water on the basis that it can negatively impact IQ, which is true at very high levels. At a recent stop in Utah Kennedy said: “The evidence against fluoride is overwhelming.”
Evidence that fluoride causes harm is not, in fact, overwhelming – though the science is nuanced. The best current evidence follows a medical adage: the dose makes the poison. Recent research shows that high levels of fluoride can have neurotoxic effects. However, those harms have not been found at levels below 1.5 parts per million – more than twice the level recommended by the CDC (0.7 parts per million).
In his tenure, Kennedy has instructed the Centers for Disease Control and Prevention (CDC) to review its guidance on fluoride, which still promotes its use in community water systems; eliminated the CDC’s office of oral health, which made those recommendations; and acted as a cheerleader to states like Utah, which have banned fluoride.
“We’re talking about quite low, very safe, very regulated levels of water fluoridation,” said Simon, adding that documented neurotoxic effects are at rates “10-15 times what people are exposed to in public water fluoridation.”
