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JAMA Pediatrics Publishes Study Connecting Fluoride in Drinking Water to Lower IQ in Children

Yesterday, the journal JAMA Pedriatrics published “Association Between Maternal Fluoride Exposure During Pregnancy and IQ Scores in Offspring in Canada,” a study that links higher levels of fluoride exposure to lower IQ scores. The study, which has not been released without criticism, measured the maternal urinary fluoride and self-reported maternal daily fluoride intake of around 600 pregnant women in six Canadian cities. About 40% of the sample population lived in cities with fluoridated drinking water and had an average maternal urinary fluoride level of 0.69 mg/L, which was contrasted with the 0.40 mg/L of the sample population that did not live in cities with fluoridated water.

Three to four years after the women gave birth, the researchers assessed the children’s IQ using the Wechsler Primary and Preschool Scale of Intelligence-III. The study concluded that higher levels of fluoride exposure during pregnancy were associated with lower IQ scores in children measured at age three to four years.