Is fluoride making us smarter?

Fluoride has been a cornerstone of dental health for decades, helping reduce tooth decay across all ages. Recently, new research covered last month in ADA News has added important insight into fluoride’s safety and effects—especially regarding community water fluoridation and cognitive health.

Key Findings from the Recent Study

A large national study published in late 2025 examined the cognitive outcomes of U.S. adolescents with varying levels of fluoride exposure through community water systems. Researchers looked at data from more than 26,000 students across the United States and followed fluoride exposure from before birth through teenage years.

The researchers found that:

Notes on the study and findings

• Typical exposure to fluoride—at levels recommended in U.S. water fluoridation programs—was linked with modestly better cognitive performance in areas like reading, math, and vocabulary during secondary school.

• The study did not find evidence of harm to cognitive functioning later in life.

• These results do not prove causation but support the idea that fluoride at recommended levels is not harmful to brain health and may coincide with positive educational outcomes.

Why This Matters

This study is especially relevant because it focuses on fluoride concentrations typical in U.S. community water fluoridation—about 0.7 milligrams per liter (mg/L)—rather than the much higher levels found in some areas of other countries. Previous research that suggested potential cognitive risks often involved significantly higher fluoride levels, far above what people in the U.S. typically encounter.

Because the study used a large, nationally representative sample and controlled for factors like socioeconomic status, the results add meaningful context to ongoing conversations about fluoride safety and public health policy.

Fluoride and Public Health Policy

While this recent research is encouraging, the ADA continues to emphasize that public health decisions should be based on the totality of high-quality evidence. Optimally fluoridated water is supported by decades of research demonstrating its safety and effectiveness in reducing tooth decay.

This topic remains under discussion in scientific and policy circles, including debates about how federal agencies regulate fluoride and how communities choose to maintain or remove water fluoridation. Still, major health organizations including the ADA, CDC, and American Academy of Pediatrics affirm the benefits of fluoridated water at recommended levels.

Take Aways

• Fluoride at recommended levels in drinking water is safe and effective for preventing dental decay.

• Recent research does not support claims that such exposure harms cognitive development; in fact, it may be linked with modest cognitive benefits.

• Fluoride remains a well-supported public health tool—especially for children and populations at higher risk of cavities.

If you have questions about fluoride use for your family’s dental care, ask us!