A Canadian study published this month in JAMA Pediatrics looked at pregnant women’s exposure to fluoride and the corresponding IQ levels of their children at ages 3-4. The researchers looked at data on maternal fluoride intake and children’s IQ from 512 mother-child pairs. According to the paper, “maternal exposure to higher levels of fluoride during pregnancy was associated with lower IQ scores in children aged 3 to 4 years” and the findings “indicate the possible need to reduce fluoride intake during pregnancy.” The authors state the study is “the first to estimate fluoride exposure in a large birth cohort receiving optimally fluoridated water.”
This study has garnered extensive media coverage, but is seen as controversial as fluoridated drinking water has long been used to prevent dental caries, particularly in children, in much of the United States.