Fluoride exposure during pregnancy linked with low IQ in children
QUEBEC CITY, Canada: Various studies have investigated the effectiveness of fluoridated water in the prevention of dental caries. A recent study has taken a step further and examined the association between a mother’s fluoride intake during pregnancy and a child’s IQ score. The findings indicate that fluoride exposure in pregnancy may affect a child’s intellectual development and should, therefore, be reduced.
According to the study, water fluoridation is supplied to approximately 66% of U.S. residents, 38% of Canadian residents and 3% of European residents, mostly owing to its perceived advantages to oral health.
The study used data from the Maternal-Infant Research on Environmental Chemicals cohort study and assessed maternal urinary fluoride concentration, self-reported daily fluoride intake and the children’s IQ test scores in 601 mother–child pairs from six major cities in Canada. More than 40% of the participants lived in communities supplied with fluoridated municipal water at the time of the study. The researchers examined the children’s IQ scores at 3 and 4 years old.
The data showed that mothers who lived in areas with fluoride added to tap water had higher concentrations of the mineral in their urine compared with those who lived in areas with nonfluoridated water. A 1 mg/L higher fluoride concentration in a mother’s urine was associated with a 4.5 lower IQ score in boys. However, the researchers found no link between a mother’s urinary fluoride level and a daughter’s IQ score. Finally, a daily increase of 1 mg fluoride in mothers was linked with a 3.66 lower IQ score for both boys and girls.
Although the study raises considerable concerns over community water fluoridation, many researchers have dismissed the findings on the grounds that it lacks sufficient proof. Therefore, more studies need to be conducted on the topic to validate the findings.
The study, titled “Association between maternal fluoride exposure during pregnancy and IQ scores in offspring in Canada,” was published online on Aug. 19, 2019, in JAMA Pediatrics, ahead of inclusion in an issue.