Children exposed to higher fluoride levels have lower IQs, a government study finds

Children exposed to higher fluoride levels have lower IQs, a government study finds

By Brenda Goodman, CNN
8 minute read
Updated 2:38 PM EST, Mon January 6, 2025

https://edition.cnn.com/2025/01/06/health/children-higher-fluoride-levels-lower-iqs-government-study/index.html

CNN
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A rigorous nine-year research review looking at the relationship between fluoride and intelligence in children concludes that as fluoride levels rise, IQ drops.

Every 1 part per million increase in fluoride in urine — a way of measuring all the sources of fluoride a person consumes — was associated with a roughly 1 point drop in a child’s IQ score, the review concluded.

Although an impact like that may seem small for any one person, on a wider scale, the study authors note, the consequences are significant, especially for those who are vulnerable because of risk factors like poverty and nutrition.

“A 5-point decrease in a population’s IQ would nearly double the number of people classified as intellectually disabled,” they write in their conclusions.

The study, which was published Monday in the journal JAMA Pediatrics, comes with a backstory. It was conducted by scientists at the government’s National Toxicology Program, which evaluates chemicals and other things people are exposed to, like Cell Phone radiation, for their potential to harm health. It began in 2015 and was subject to several rounds of reviews in a process that some critics charge was designed to delay its public release.

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The full review was finally published as a lengthy monograph in August, and in September, the study became the basis of a federal judge’s ruling ordering the US Environmental Protection Agency to further regulate fluoride to protect children’s intellectual development.

“Simply put, the risk to health at exposure levels in United States drinking water is sufficiently high to trigger regulatory response by the EPA” under federal law, US District Judge Edward Chen wrote in the ruling.

In November, Robert F. Kennedy Jr., President-elect Donald Trump’s pick for US Health and Human Services secretary, made headlines after he called fluoride “an industrial waste” and pledged that the Trump administration would advise utilities to stop adding to public water supplies.

Fluoride is a naturally occurring mineral that’s found in soil, rocks and water to varying degrees. It is also a byproduct of fertilizer production. On the recommendation of the US Centers for Disease Control and Prevention and the World Health Organization, many cities have added fluoride to their treated drinking water for decades to protect teeth from cavities.

As it washes over teeth, fluoride can stop early decay by putting minerals back into tooth enamel. It also makes teeth more resistant to acid and interferes with bacteria’s ability erode teeth.

In some places, including areas that have well water that’s naturally high in fluoride, children were getting so much fluoride that it left streaks and spots on their teeth, a condition called dental fluorosis. In 2015, HHS lowered its recommended levels for fluoride in drinking water from a range of 0.7 parts per million to 1.2 parts per million to 0.7 parts per million, to prevent fluorosis.

The CDC reiterated its faith in the health benefits of fluoride in 2015, naming water fluoridation one of the “10 Greatest Public Health Achievements of the 21st Century.”

Now, though, environmental health experts say health agencies need to reassess the risks and benefits of fluoride, because of its potential neurotoxicity.