[nneonneo]

Note that the association is for levels far higher than those used in drinking water. An updated meta-review (https://www.nature.com/articles/s41598-021-99688-w) also suggests an association between high fluoride intake and lower IQ, but notes that the quality of evidence is very low. It suggests that there is no evidence that low-to-moderate levels, like those used in drinking water, pose any neurotoxic effect; if there are effects, they may only be present at levels 3-10x higher than recommended fluoridation levels.