In the days before the election, Robert F. Kennedy Jr., who is expected to play a key role overseeing federal health agencies in the second Trump administration, alarmed many health officials by calling for the removal of fluoride from public drinking water. This would overturn decades of public health doctrine and is already incurring the wrath of some influential clinicians.

Here’s the thing: It’s not an entirely crazy idea.

I know what you’re thinking: “Really? We are going to take the rantings of this infamous crank, who advocated against vaccines for years, seriously?” Well, bear with me while I explain how evolving research supports a reexamination of America’s fluoridation policy.

Fluoride is a naturally occurring mineral that has long been known to prevent tooth decay. Bacteria in the mouth produce acid that dissolves the tooth’s surface, eventually leading to cavities. Fluoride replenishes lost minerals from wear and tear and strengthens dental enamel.

Since 1962, the U.S. Public Health Service has recommended adding fluoride to public drinking water. The Centers for Disease Control and Prevention reports that this practice has reduced cavities by about 25 percent and hails it as one of the 20th century’s 10 greatest public health achievements.

Over the years, research has shown that fluoride is not harmless. Higher levels can lead to problems such as tooth discoloration, bone deformities and thyroid diseases. In recognition of these risks, as well as the fact that most people are now getting fluoride through toothpaste, the Public Health Service lowered the recommended fluoride concentration in drinking water in 2015. In 2019, the CDC urged parents to supervise young children’s use of toothpaste to guard against excessive fluoride ingestion.

Multiple studies also show that neonatal fluoride exposure might interfere with brain development. A JAMA Pediatrics study concluded that Canadian women who drank fluoridated water during pregnancy had children with lower IQ scores at ages 3 to 4 years old. There was no statistically significant effect on girls, but IQ scores of boys born to women with higher fluoride consumption were nearly 4.5 points lower.

Another Canadian study found that exposed girls were impacted, with worse cognitive flexibility and executive function. Three studies from Mexico found a link between fluoride intake during pregnancy and a significant drop in IQ, attention-deficit/hyperactivity symptoms and cognitive development problems.

Earlier this year, a U.S. study published in JAMA Network Open found that prenatal fluoride exposure was associated with children developing neurobehavioral problems.

Researchers followed 229 women in the Los Angeles area from pregnancy through about the third year of their child’s life and linked higher amounts of fluoride by the expectant mothers to nearly double the odds of the child having problems such as anxiety and emotional instability.

This study, which was funded in part by the National Institutes of Health and the Environmental Protection Agency, generated significant controversy. Anti-fluoridation groups seized upon it to justify their crusade, while organizations such as the American Dental Association issued statements doubling down on the benefits of water fluoridation.

Both sides have legitimate points. The safety of low-level fluoridation has been demonstrated by decades of research, though emerging studies suggest it could be a risk to pregnant women.

Moreover, although the data are clear that community fluoridation dramatically reduced cavities before fluoride toothpaste became available, the current benefit is much smaller. Indeed, a 2024 Cochrane review — considered the gold standard of medical reviews — concluded that fluoridating water today “may” lead to “slightly less” decay in kids’ teeth. “However, these results also included the possibility of little or no difference in tooth decay,” the authors wrote.

Currently, about 72 percent of Americans receive fluoridated water. At least a dozen states have laws mandating fluoridation. One — Hawaii — has banned it. Most others leave it to individual localities. Municipalities that don’t add fluoride to drinking water include Portland, Oregon, and Wichita, where voters have repeatedly rejected fluoridation proposals. Other localities have been joining them; since 2023, towns in North Carolina, Florida, Pennsylvania and Texas have decided to stop the practice.

Interestingly, most Western European countries, including Denmark, France, Germany, Italy, the Netherlands, Norway and Sweden, have ended public water fluoridation. If Kennedy succeeds in persuading Trump to recommend against fluoridation, he would actually be aligning the United States with peer countries. That could result in a slight increase in tooth decay, but it could also benefit Americans by reducing prenatal exposure.

To be clear, I am deeply concerned about the public health implications of a second Trump administration. His own penchant for spreading medical misinformation and Kennedy’s long history of antiscience propagandism give me nightmares.

But I would caution the medical and scientific community against knee-jerk reactions. Not every proposal from Trump and Kennedy is a five-alarm fire. Stopping fluoridation does not rise to the same level of concern as, for example, defunding schools that require childhood vaccines. Medical experts — and the American public — need to save their outrage for when it’s really warranted.

Leana S. Wen, a Washington Post contributing columnist who is an emergency physician and clinical associate professor at George Washington University.