The Food and Drug Administration (FDA) announced Tuesday it will be moving to take ingestible prescription fluoride products for children off the market, citing concerns that the mineral alters the gut microbiome of children.
In a press release, the agency said ingestible fluoride products differ from topical goods like toothpaste and mouthwash because they have been “shown to alter the gut microbiome, which is of magnified concern given the early development of the gut microbiome in childhood.”
The FDA has set an Oct. 31 deadline for completing a safety review and public comment period for removing ingestible fluoride.
Ingestible fluoride products are prescribed for children who are at a high risk of tooth decay. The majority of municipal water systems in the U.S. also fluoridate their water, but ingestible fluoride may be prescribed if a child lives in an area where the water has low concentrations of fluoride. The mineral is naturally occurring and protective against cavities.
While the benefits of fluoride are most often associated with topical products, ingesting fluoride allows the mineral to incorporate into teeth, making them more resistant to cavities.
Health and Human Services Secretary Robert F. Kennedy Jr. said the removal of ingestible fluoride was “long overdue.” Kennedy has long spoken out against the use of fluoride in public health, saying earlier this year he would direct the Centers for Disease Control and Prevention (CDC) to stop recommending fluoride in drinking water.
FDA Commissioner Marty Makary said in a statement, “The best way to prevent cavities in children is by avoiding excessive sugar intake and good dental hygiene, not by altering a child’s microbiome.”
“I am instructing our Center for Drug Evaluation and Research to evaluate the evidence regarding the risks of systemic fluoride exposure from FDA-regulated pediatric ingestible fluoride prescription drug products to better inform parents and the medical community on this emerging area,” he added. “When it comes to children, we should err on the side of safety.”
The agency cited several analyses, including one published in 2023 that found “acute fluoride toxicity” can “detrimentally perturb the normal microbiome.”
“Overall, while fluoride exposure does appear to impact the human and animal microbiome, the long-term consequences of this requires further study,” the article stated, also noting “evidence suggests that the use of fluoride containing oral hygiene products may have beneficial effects on the oral microbiome regarding caries prevention.”
Another analysis that the FDA cited, published earlier this year, concluded that “fluoride at low levels (<2 mg L–1 NaF in humans and <25 mg L–1 NaF in animals) did not affect gut microbiota.” In the U.S., water fluoridation levels are 0.7 milligrams per liter.