- Fluoride has become almost synonymous with U.S. public water supplies since the mineral is in an estimated 74.4% of peoples’ drinking water.
- A new study suggests when pregnant women consume fluoridated drinking water, it could decrease their children’s brain function.
- Fluoridated water has been touted for its ability to prevent tooth decay.
Although the naturally occurring mineral is usually touted for its ability to help prevent tooth decay, a new study suggests it could actually affect the brain development of children whose mothers drank fluoridated water while pregnant.
A new study, published August 20 in JAMA Pediatrics, looked at 601 Canadian children between the ages of 3 and 4 whose moms either did or didn’t live in regions where fluoride was in the water supply while they were pregnant. After giving the children IQ tests, researchers found that kids whose moms lived in non-fluoridated water regions had higher IQs than the kids whose moms lived in fluoridated water regions.
The findings rattled researchers since healthcare providers have always considered fluoride safe for pregnant women, and beneficial to people overall.
“This decision to publish this article was not easy. Given the nature of the findings and their potential implications, we subjected it to additional scrutiny for its methods and the presentation of its findings,” lead researcher Dr. Dimitri A. Christakis, wrote in an editorial letter. “We hope that purveyors and consumers of these findings are mindful of that as the implications of this study are debated in the public arena.”
Fluoridated water prevents tooth decay
Fluoridated city water has been available in the United States since 1945, when Grand Rapids, Michigan, added the mineral to its water supply following scientific research that showed its ability to promote oral health.
Now, the majority of the U.S. population has fluoride in their water, which according to the Centers for Disease Control and Prevention prevents cavities and the need for fillings, and causes “less pain and suffering because of tooth decay.”
In fact, the decline of tooth decay in the country after fluoride was introduced into water lead the CDC to call water fluoridation one of 10 great public health achievements of the 20th century.
The American College of Obstetricians and Gynecologists also supports fluoride use during pregnancy and recommends that doctors tell their pregnant patients to brush their teeth twice daily with fluoride-containing toothpaste.
New findings suggest fluoride could unintended consequences in the brain
But the researchers’ findings suggest fluoridated water may have unintended consequences. Specifically, they found that for every 1 milligram of fluoride a woman consumed through her water daily, there was a 3.7 point decrease in her child’s IQ score when the child was tested at age 3 or 4.
These findings held true for both boys and girls when they measured fluoride through the women’s overall fluid intake, but only boys’ IQ seemed to be affected when researchers looked at the women’s fluoride concentration in urine.
To measure IQ, researchers used the The Wechsler Preschool and Primary Scale of Intelligence, which takes into account verbal and performance skills. The highest a child can score is 266 since there are 14 subtests that are worth a maximum of 19 points each. The average score for each subtest is between 7 and 12.
This isn’t the first time health professionals have considered if fluoride might have a downside. Fluorosis, for one, is a condition where to much fluoride in water can cause a person’s tooth enamel to decay and, in extreme cases, leads to pits in a person’s teeth, according to the CDC. But the condition is unusual and communities have taken steps to limit the amount of fluoride in public water supplies to prevent it.
The researchers only looked at Canadian women and their children, so the results aren’t generalizable to other parts of the world with fluoridated water. Additionally, the researchers used the pregnant women’s urine samples to measure fluoride intake, but said this measurement tool isn’t always perfectly precise and could’ve therefore skewed the results of the study. When the researchers considered women’s fluid intake, they were relying on self-reported data, which isn’t fool-proof.
The researchers’ findings raise an important question about the safety of city water supplies. Still, expecting moms shouldn’t write off fluoridated tap water until more conclusive studies are done.
*Original article online at https://www.insider.com/drinking-fluoride-water-during-pregnancy-linked-to-lower-childhood-iqs-2019-8