Water Fluoridation Study Finds No Evidence of Cognitive Harm
New PNAS study using Wisconsin cohort data finds no negative association between community water fluoridation and adolescent IQ or cognitive performance across the life course.
By
Kerri Miller
April 23, 2026
Clinical Scorecard: Water Fluoridation Study Finds No Evidence of Cognitive Harm
At a Glance
Category Detail
Condition Cognitive Functioning and IQ Key Mechanisms Assessment of fluoride exposure and its potential impact on cognitive outcomes across the lifespan. Target Population Adolescents and adults in Wisconsin, USA. Care Setting Community settings with varying levels of water fluoridation.
Key Highlights
No significant association found between water fluoridation and cognitive outcomes. Study utilized a large, representative sample from the Wisconsin Longitudinal Study. Cognitive assessments included standardized tests at multiple life stages. Findings contrast with recent state-level decisions to end community water fluoridation. Study accounted for socioeconomic factors and geographic mobility. Guideline-Based Recommendations
Diagnosis
No diagnostic criteria established; focus on cognitive assessment. Management
Continue community water fluoridation based on lack of evidence for cognitive harm. Monitoring & Follow-up
Monitor cognitive outcomes in populations with varying fluoride exposure. Risks
No identified risks associated with community water fluoridation regarding cognitive function. Patient & Prescribing Data
Individuals exposed to varying levels of fluoride in drinking water.
Fluoride exposure classification includes both community fluoridation and naturally occurring fluoride.
Clinical Best Practices
Utilize population-representative samples for future studies on fluoride exposure. Consider socioeconomic factors when assessing cognitive outcomes related to fluoride. References
