Fluoride in pregnancy may harm child’s brain development: study

A new study suggests a link between greater fluoride intake in pregnancy and toddlers with behavioral problems.

Children in the womb exposed to higher levels of fluoride — a mineral found naturally in water in varying amounts — later were more likely to experience temper tantrums, headaches, stomachaches, anxiety and symptoms linked to autism, according to research published Monday in JAMA Network Open.

“Exposure to fluoride during pregnancy does not mean that a child will experience greater neurobehavioral problems,” senior study author Tracy Bastain, an associate professor of clinical population and public health sciences at the University of Southern California’s Keck School of Medicine, told The Post.

“We found an association between higher prenatal exposure and more neurobehavioral problems at age 3 but more studies are needed to establish a causal link,” she explained.

Data for the study came from USC’s MADRES Center for Environmental Health Disparities.

MADRES follows predominantly Hispanic families in Los Angeles from pregnancy throughout childhood.

Researchers calculated fluoride exposure from urine samples collected from 229 pregnant moms during their third trimester.

Children whose mothers had higher levels of fluoride were 83% more likely to show “internalizing” behavioral problems, the study authors said.

No tie was found to “externalizing behaviors” such as aggression and attention problems.

“This is the first US-based study to examine this association,” lead study author Ashley Malin, an assistant professor of epidemiology at the University of Florida’s College of Public Health and Health Professions and College of Medicine, said in a statement.

“Our findings are noteworthy, given that the women in this study were exposed to pretty low levels of fluoride — levels that are typical of those living in fluoridated regions within North America,” she added.

Communities have been adding fluoride to their drinking water for decades to help prevent tooth decay.

Fluoride has been shown to strengthen enamel, inhibit the growth of bacteria and replenish lost minerals.

According to the Centers for Disease Control and Prevention, as of 2020, more than 209 million people, or 72.7% of the US population, receive fluoridated water through public water systems.

However, the anti-fluoridation movement is hoping to reduce that number. Anti-fluoridationists say fluoridation violates their health freedom, with some even successfully pushing for bans in their cities.

Others point to a 2019 Canadian study in the journal JAMA Pediatrics that tied higher levels of fluoride exposure during pregnancy to lower IQ scores for 3- and 4-year-olds.

The authors of that study stopped short of recommending fluoridation bans but did say “these findings indicate the possible need to reduce fluoride intake during pregnancy.”

The authors of the new study are also not saying that water should not be fluoridated, instead suggesting the “need to establish recommendations for limiting fluoride exposure during the prenatal period.”

“There are no known benefits to the fetus from ingesting fluoride,” Malin said. “And yet now we have several studies conducted in North America suggesting that there may be a pretty significant risk to the developing brain during that time.”

Bastain told The Post that studies conducted in North America over the last seven years have associated exposure to fluoride during pregnancy with adverse outcomes such as reduction in IQ, greater ADHD symptoms and altered executive function and cognition.

Bastain and her colleagues plan to explore how exposure to fluoride during pregnancy affects brain development among infants.

In the meantime, the research team suggests pregnant women drink filtered tap water — “even some tabletop pitcher filters do a pretty good job of filtering fluoride,” Bastain said.