Robert F. Kennedy Jr. says he'll be serving in a major health care policy role in the upcoming Trump administration, where his to-do list includes telling local communities to stop adding fluoride to drinking water.

"On January 20, the Trump White House will advise all U.S. water systems to remove fluoride from public water," Kennedy posted to the social media site X.

There is no federal mandate requiring fluoride in water.

Fluoride is a mineral long proven to strengthen teeth and prevent cavities when added to water in small amounts. Local utilities across the country have been putting fluoride in water since 1945 to help fight tooth decay. The CDC considers the practice one of the great public health achievements of the 20th century.

Kennedy calls fluoride "industrial waste," linking it to arthritis, bone fractures, cancer and cognitive decline.

"The faster it goes out the better," Kennedy said in an interview with NBC News. "I'm not going to compel anyone to take it out. But I'm going to advise the water districts about their legal liability, their legal obligation."

In defending his push to take out fluoride, Kennedy points to a recent ruling by a federal judge that found enough of a risk from fluoridated water to warrant ordering the Environmental Protection Agency to study the effect on children's IQ. The opinion did not say one way or another if there is a health risk.

"This finding does not conclude with certainty that fluoridated water is injurious to public health," it said.

Too much fluoride in water can be a health hazard for children, according to a government backed study.

That found levels of fluoride two times greater than the recommended amount in drinking water "are associated with lower IQ in children," but not adults.

The report, by the National Toxicology Program, said more research is needed to understand the potential for lower amounts of fluoride to affect children's IQ.

The CDC says there's not "convincing scientific evidence" showing any adverse health effects. The American Dental Association has long advocated for fluoride in water, calling it a "safe and effective" way to prevent at least 25% of tooth decay in children and adults.

"It's one of those very few public health interventions that benefits everyone regardless of the color of their skin, their socioeconomic status, their access or lack of access to dental care," said Dr. Russell Maier, associate dean for graduate medical education at Pacific Northwest University. "If fluoride, which has been in public water systems for 80 years, had significant health problems, we'd know."

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