Another New Study Reinforces Safety of Fluoridation
A new study strengthens confidence about the safety of fluoride in drinking water, bolstering other recently published research that finds no link between fluoridated water and cognitive deficits. The results of the analysis have been widely reported by NBC News Science News, ABC News, and other national media. The study was published by the journal of the Proceedings of the National Academy of Sciences, or PNAS.
The authors analyzed data from the Wisconsin Longitudinal Study, one of the longest-running and most comprehensive social science datasets in the U.S. Collected from over 10,000 Wisconsin residents exposed to water both with and without fluoride, the evidence includes the results of cognitive tests. The initial tests were given in the participants’ senior year of high school in 1957. Six additional tests were administered over the subsequent 60 years, resulting in a remarkable time-series. In concluding their analysis, the PNAS authors reported “no evidence that [water fluoridation] is negatively associated with adolescent IQ or adult cognitive functioning.”
Opponents of water fluoridation point to a variety of findings to raise concerns about whether fluoride exposure reduces children’s IQ scores. However, as NBC News explained, those studies “were conducted in China or other countries with much higher fluoride concentrations than allowed in the U.S.” The PNAS study’s lead author, Rob Warren, told ABC News that the fluoride exposures he and his colleagues studied “are much more relevant to policy questions than a lot of other research.”
As state and local officials take a fresh look at water fluoridation policies and practices, they can “do that in light of the best possible evidence about all the benefits and all the risks”, Warren said, “and hopefully this [study] makes a real contribution to that.”
