Dr Mercola - What's Driving the Decline in IQ Scores?

Fluoride Exposure Linked to Lower IQ

The featured study didn’t look in-depth into the environmental exposures that could be affecting IQ but other studies have. In the U.S., two-thirds of Americans’ tap water contains fluoride, which is added under the guise of preventing cavities. Water fluoridation continues to occur in the majority of the U.S. even as research stacks up that fluoride is a neurotoxin that can harm brain function. Fluoride also leaches lead out of old pipes, which further magnifies its neurological risks.

A study of Mexican women and children, published in 2017, found that higher exposure to fluoride while in utero is associated with lower scores on tests of cognitive function in childhood, both at the age of 4 and 6 to 12 years.3

While the children’s fluoride levels at ages 4 and 6 to 12 were not associated with their intelligence, the study found that exposure that occurs prenatally was linked to lower intelligence scores. In fact, women with higher levels of fluoride in their urine during pregnancy were more likely to have children with lower intelligence.

Specifically, each 0.5 milligram per liter increase in pregnant women’s fluoride levels was associated with a reduction of 3.15 and 2.5 points on the children’s General Cognitive Index (GCI) and Wechsler Abbreviated Scale of Intelligence (WASI) scores, respectively. In 2012, Harvard researchers also revealed that children living in high-fluoride areas had significantly lower IQ scores than those who lived in low-fluoride areas4 and suggested high fluoride exposure may have an adverse effect on children’s neurodevelopment.

Then, in 2014, a review in Lancet Neurology classified fluoride as one of only 11 chemicals "known to cause developmental neurotoxicity in human beings,"5 alongside other known neurotoxins such as lead, methylmercury, arsenic and toluene. Among the proposed mechanisms of harm, studies have shown fluoride can:........................................