Increased Fluoride Levels Associated with Decreased IQ Scores in Children
Recent studies have pinpointed a threshold of 1.5 milligrams of fluoride per liter as a significant concern for child development safety.
In the wake of an August 2024 U.S. government report that linked elevated fluoride levels in drinking water to lower IQ levels in children, a fresh review by the National Institutes of Health seems to corroborate these findings.
The studies analyzed fluoride concentrations in drinking water and urine, utilizing urinary fluoride as an indicator of overall fluoride exposure.
74 Studies Analyzed
Out of the 74 studies reviewed, 64 indicated a correlation between higher fluoride levels and lower IQs in children, with this association being characterized as moderate to strong.
Furthermore, thirty-one studies indicated a dose-response relationship, implying that increased fluoride levels in drinking water corresponded with further declines in children’s IQ scores.
However, this association with lower IQ scores was only observed when fluoride levels in drinking water exceeded 1.5 mg/L, which is higher than the current standard of 0.7 mg/L set for fluoride in drinking water.
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When assessing urinary fluoride levels, researchers found that each increase of 1 mg/L in urinary fluoride was linked to an average decline of between 1.14 and 1.63 IQ points.
Fluoride is capable of crossing the blood-brain barrier and can accumulate in brain regions associated with cognition and memory, although the exact effects on the brain remain uncertain.
The findings from this study could help shape future risk-benefit analyses concerning fluoride exposure, particularly emphasizing the notable contributions from water and beverages made with fluoridated water, such as soft drinks, fruit juices, beers, and certain bottled waters, towards overall fluoride intake.
The World Health Organization has designated 1.5 mg/L as the safe upper intake limit for fluoride in drinking water, while the U.S. Public Health Service recommends a concentration of 0.7 mg/L. Nonetheless, “fluoride levels exceeding 1.5 mg/L are prevalent in wells and municipal water systems serving nearly 3 million individuals across the United States,” stated Christine Bruske Flowers, director of communications at the National Institutes of Health, in an interview with The Epoch Times.
Food & Water Watch v. EPA
In a federal court case in California in September 2024, the environmental nonprofit Food & Water Watch filed suit against the EPA, claiming that fluoridating drinking water is detrimental. The judge ruled in favor of Food & Water Watch, asserting that the existing fluoride level in drinking water (0.7 mg/L) presents an “unreasonable risk” to children’s IQ.
This ruling was based on the NTP’s report, which found that fluoride concentrations near the EPA’s current standard posed a neurodevelopment risk.
The EPA is now obligated to take corrective action to mitigate this risk, potentially resulting in significant changes to drinking water treatment practices.
Experts Divided
Despite the findings of the review, experts remain divided on the implications of the results.
One of the points he raised in contrast to the NTP’s study was the use of urinary fluoride as a metric for long-term fluoride exposure, asserting that such measures are inadequate due to “fluoride’s short half-life and significant daily variability.”
Flowers underscored the long-standing public health benefits of fluoridated water, particularly in reducing dental decay and enhancing overall oral health.
However, increasing routes of fluoride exposure also pose risks to pregnant women and children.
Fluoride consumption via foods and beverages made from fluoridated water, toothpaste, and mouth rinses may elevate total fluoride exposure for children and pregnant women, potentially impacting fetal, infant, and child neurodevelopment, Flowers noted.
Mahalaha pointed out that the fluoride concentration in drinking water is significantly less than that found in toothpaste and mouth rinses, making it crucial to prevent children from swallowing these products.
Warnings against ingestion are included on toothpaste tubes, as excessive fluoride intake can be harmful.
“When applying toothpaste on a child’s toothbrush, a small amount (less than a pea-sized portion) is adequate and secure,” she advised.
“From a public health standpoint, my view is that excessive doses of ingested fluoride, alongside factors such as sugar consumption, processed foods, social media, and screen exposure, negatively impact child development,” Mahalaha concluded.
