A landmark NIH-funded study published this week offers evidence supporting the benefits and safety of community water fluoridation, The study directly refutes the false claims Secretary Kennedy has made about community water fluoridation.
Drawing on data from nearly 27,000 individuals across more than 1,000 U.S. high schools the research finds that children raised with recommended levels of fluoride in their drinking water tend to perform better on standardized tests in math, reading, and vocabulary, compared to peers in non-fluoridated communities.
The study reported no negative cognitive effects among older adults (around age 60) exposed to the same fluoride levels during their youth (despite what Kennedy says).
Childhood fluoride exposure and cognition across the life course | Science Advances
Key Findings
- Improved High School Test Scores
- The study used the “High School and Beyond” cohort, a nationally representative sample of students followed from 1980 into the 2020s.
- Adolescents who drank optimal fluoride (around 0.7 mg/L, the U.S. public health recommendation) scored modestly but consistently higher in mathematics, reading comprehension, and vocabulary.
- The cognitive advantage was small (about 7% of a standard deviation), but statistically clear.
- No Evidence of Harm Later in Life
- When researchers followed up with participants around age 60, they found no statistically significant link between childhood fluoride in drinking water and cognitive function (memory, fluency, attention) in older adulthood.
- Robustness & Quality
- The study controlled for a wide range of confounders (e.g., socioeconomic status, residential moves) and ran sensitivity analyses to rule out alternative explanations.
- By focusing on fluoride exposures typical of U.S. water systems, it avoids the critiques of earlier studies that examined much higher levels found overseas.
Childhood fluoride exposure and cognition across the life course | Science Advances
- Fluoridation is a Local Decision in Arizona: In Arizona, municipal or county governments decide whether to fluoridate their water systems. This new study provides strong, locally relevant evidence to support continued or renewed fluoridation.
- Leveraging the Study for Advocacy: AZPHA members can bookmark and reference this study in discussions with city councils, county boards, or public health committees. It’s not just theory — it’s real-world, long-term data from U.S. communities.
- Countering Misinformation: For years, opponents of fluoridation have claimed U.S.-level fluoride harms IQ or health. This rigorous, NIH-funded research directly refutes those claims at the very levels used in public systems.
- Dental Health + Broader Health Equity: We know that fluoridation reduces tooth decay by at least 25% in children and adults. With this new cognitive data in hand, AZPHA can make an even stronger public health case — not just for preventing cavities, but for supporting brain development and long-term wellness.
Call to Action
- Share the Evidence: Use blog posts, newsletters, and presentations to spread awareness among elected officials, water utility managers, and community stakeholders.
- Engage the Community: Host forums, webinars, or coffee talks in your jurisdiction to explain the significance of the study in plain language.
- Policy Letters with Impact: When writing to local decision-makers, include a link to the full study (Science Advances, DOI: 10.1126/sciadv.adz0757) as well as key take-home messages (academic performance, safety, long-term benefits).
- Align with Other Public Health Messaging: Integrate these findings into broader oral health and local prevention strategies — fluoridation isn’t just about teeth, it’s about lifelong health.
Childhood fluoride exposure and cognition across the life course | Science Advances
