Even before Robert F. Kennedy Jr. took office as health secretary, he promised to take action on water fluoridation. He would provide “good information” to municipalities, which regulate the water supply, and “fluoride will disappear,” he said in November.

 

In just over a couple of months, some places have made this a reality. Utah and Florida have both banned the addition of fluoride in water, with advocates of the laws like Kennedy arguing that adding the mineral to water poses a risk to children’s developing brains.

A new study tried to predict the consequences if the rest of the nation were to follow suit. In five years, the researchers estimated, 7.5% more U.S. children ages 0-19 would get cavities, affecting 25.4 million additional teeth and costing the country around $9.8 billion. While these findings are worrisome, several experts said, they were unsure if the new data would move the needle on a debate that has become so heated and politicized.