Higher fluoride levels result in low intelligence among children: Study

Excessive exposure to fluoride in tap water and other dental products could hamper child's intelligence, shows new study.

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Fluoride affect child's intelligent
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Women who had higher levels of fluoride during pregnancy tend to give birth to children with lower intelligence, shows a new study. Though drinking water and brushing teeth are good habits, they could have severe consequences for infants, it was found.

Those children exposed to higher levels of fluoride while in the womb tend to have less intelligent compared with those not exposed to fluoride, reiterating several past research findings showing similar results.

Fluoride is a chemical reagent which is often added to drinking water and dental products including toothpaste and mouthwash to prevent oral cavities. Drinking of fluoridated water could help to control tooth decay both in children and adults by around 25%, according to some studies conducted in the past.

However, a 2014 study suggested that high levels of fluoride in pregnant mothers might cause cognitive deficit in infants. A research team headed by Howard Hu, founding dean of the Dalla Lana School of Public Health at the University of Toronto, conducted a study on how prenatal exposure to the higher level of fluoride affects a child's intelligent.

They studied 299 women and their infants in their project on the Early Life Exposures in Mexico to Environmental Toxicants. From the urine samples collected from every expectant mother, and from their offsprings when they were aged 6 to 12 years, they were able to determine the level of fluoride exposure.

The results showed that mothers with higher levels of fluoride in their urine during pregnancy has more probability to children with lower IQ score leading to the finding that fluoride might be a developmental neurotoxicant which affects brain while exposing children to it from the stage of womb itself.

The intelligence of each child was assessed at 4 years using the General Cognitive Index(GCI) of the McCarthy Scales of Children's Abilities, and also between the ages of 6 to 12 years using the Wechsler Abbreviated Scale of Intelligence (WASI).

"For every 0.5 milligrams per litre increase in expectant mothers'fluoride levels, their offspring's GCI and WASI scores were reduced by 3.15 and 2.5 points," said researchers. Even prenatal fluoride exposure may impact neurodevelopment in a way that reduces a children's intelligence, they found.

"Our study shows that the growing fetal nervous system may be adversely affected by higher levels of fluoride exposure. It also suggests that the prenatal nervous system may be more sensitive to fluoride compared to that of school-aged children," said Howard.

The researchers mark that their findings need to be confirmed in other people before any firm conclusions could be made about the link between prenatal fluoride exposure and child intelligence.

This article was first published on October 5, 2017