A recent analysis has confirmed that exposure to high levels of fluoride can negatively impact children’s cognitive development. According to the National Institutes of Health (NIH), concentrations of fluoride in drinking water greater than 1.5 milligrams per liter (mg/L) are associated with lower IQ scores in children, reinforcing previous data released in a U.S. government report.
The study, published in JAMA Pediatrics, is the largest meta-analysis ever conducted on the health impacts of fluoride. After nine years of research, the U.S. National Toxicology Program reviewed 74 studies, of which 64 indicated a direct link between higher levels of fluoride exposure and lower childhood intelligence.
Fluoride Exposure Limits
The analysis found that the relationship between fluoride and lower IQ is significant only when concentrations in water exceed 1.5 mg/L, which is higher than the current standard of 0.7 mg/L adopted by the U.S. Environmental Protection Agency (EPA). Additionally, the report highlighted that a 1 mg/L increase in urinary fluoride levels was associated with an average reduction of 1.14 to 1.63 points in IQ.
These results prompted a federal court to order the EPA to review its water fluoridation standards. The decision was prompted by a lawsuit from the environmental organization Food & Water Watch, which argued that current levels pose a significant risk to children’s neurodevelopment.
Public health impacts
Fluoride can be ingested through a variety of sources, including fluoridated drinking water, foods, beverages, and oral hygiene products. Experts point out that fluoride’s ability to cross the blood-brain barrier and accumulate in areas of the brain linked to cognition and memory may explain its impacts on neurocognitive development, although the mechanisms are not yet fully understood.
Despite these findings, there is disagreement among experts. Some point out that fluoride at safe levels plays a key role in preventing tooth decay. Critics have also questioned the study’s methodology, such as the use of urinary fluoride as an indicator of exposure, due to its variability.
Final thoughts
While fluoride is widely recognized as an effective tool for oral health, increasing exposure through different sources may pose additional risks, especially for children and pregnant women. Researchers emphasize the need for more detailed risk assessments to balance the benefits of fluoridation with potential negative impacts on neurodevelopment.
These new data reinforce the importance of public health strategies to monitor and adjust fluoride exposure levels, ensuring both the protection of oral health and children’s cognitive development.
