New research Further Debunks Claims Linking Fluoride to Lower IQ
The case for removing fluoride from the drinking water supply just got weaker. Research published today shows no link between water fluoridation and declining cognition in children or adults.
Researchers examined the education and medical records of a large, nationally representative group of Americans. They found no evidence that water fluoridation was associated with lower test scores in high school or lower cognition scores later in life. The findings undermine a common argument against adding fluoride to drinking water, the researchers say.
“If fluoride lowers your IQ, then we should see lower test scores in places where they fluoridate the water.and we didn’t, at all,” lead author John Warren, a sociologist and demographer at the University of Minnesota’s Minnesota Population center, told Gizmodo.
The Fluoride Controversy
Water fluoridation has long been blamed for a range of health problems by some groups.
Robert F. Kennedy Jr. has argued that fluoride causes widespread IQ loss and increased bone cancer, as a notable example. as U.S. Secretary of Health and Human Services under the second Trump administration, he stated he would tell the CDC to no longer recommend water fluoridation nationally.
Many claims made about fluoride are unsubstantiated by current data, including a supposed cancer risk. However,a scientific debate has existed regarding whether water fluoridation can affect children’s IQ. A review published in January by scientists at the National Institutes of Health found a possible link between lower IQ levels in children and greater fluoride exposure.
Study researcher John Warren notes, as others have, that this review largely focused on studies examining much higher and possibly toxic levels of fluoride exposure than typically seen in the U.S. Furthermore, limited research has examined this possible link among American children.
“It really struck me that there was a problem with that meta-analysis,” Warren said.
No Evidence of Harm
Warren and his colleagues believed they could provide a more definitive answer. Their research offers strong evidence against the claim that community water fluoridation negatively impacts cognitive progress.