A new study suggests a link between high levels of fluoride and lowered IQ. It's heating up arguments over fluoridating drinking water, which dentists say is critical for protecting teeth.

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Fluoridating the public water supply has been common practice for nearly 80 years in the U.S. It's an acclaimed public health intervention that helps prevent cavities. For just as long, some have raised concerns about the practice that can veer from evidence-based to unsubstantiated conspiracy. An analysis by government researchers, published Monday in JAMA Pediatrics, is adding to the debate. The research found that exposing babies and kids to high levels of fluoride might be associated with neurodevelopmental harm. Frankly, it's a lot to digest — so we invited health correspondent Pien Huang onto the show to wade through the debate.

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2024 was full of science news. There was a total solar eclipse, the Paris Olympics, elections in the United States and elsewhere, technological breakthroughs and many space launches. But perhaps above all, it was a huge year in health. So, today, we're talking through some of 2024's biggest health stories — from what's in our drinking water supply, to bird flu, obesity drugs and this year's record heat. They're also the stories we think will continue to be big in 2025. See you in the new year, Short Wavers! <3

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Florida's surgeon general, Dr. Joseph Ladapo, cited developmental concerns from higher levels of fluoride than are found in most U.S. water supplies.

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A Canadian study suggests that fluoride consumed by pregnant women can affect the IQ of their children. No single study provides definitive answers, but the findings will no doubt stir debate.

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If the whir of a drill as it bores into a molar terrifies you, we have some good news. Dentists have better ways to prevent cavities in adults with fluoride treatments most commonly used on kids.

Excess fluoride consumption is leading to tiny white marks on many people's teeth. It's mainly a cosmetic problem, but one that could be solved by lowering the fluoride in drinking water.

Despite evidence to the contrary, many Americans believe cellphones cause cancer and that health officials are covering it up. Discredited theories about vaccines and fluoridation also remain popular.