A large-scale study has found no evidence that fluoride in drinking water affects intelligence or cognitive abilities at any age. The research, published April 13 in the Proceedings of the National Academy of Sciences (PNAS), analyzed data from thousands of participants across multiple regions, comparing those exposed to fluoridated water with those who were not. The results showed no measurable differences in IQ scores or cognitive decline between the two groups.

The study addresses longstanding public concern about potential neurological effects of fluoride, particularly in children. While some earlier research suggested possible links to lower IQ, this new analysis—one of the largest to date—found no such connection. Experts note that fluoride remains a proven method for preventing tooth decay and cavities, a critical public health measure that reduces dental disease and associated healthcare costs.

Fluoridation of public water supplies began in the U.S. in the 1940s and has since expanded to millions of people worldwide. The Centers for Disease Control and Prevention (CDC) lists water fluoridation as one of the top 10 public health achievements of the 20th century due to its effectiveness in improving dental health. The agency continues to recommend fluoride levels between 0.7 and 1.2 parts per million in drinking water to balance benefits and safety.

Researchers used data from the Copenhagen Aging and Midlife Biobank and the Danish National Birth Cohort, two major population studies in Denmark. The analysis included cognitive assessments from children and older adults, ensuring broad age coverage. The findings provide reassurance to communities that rely on fluoridated water, particularly those with concerns about potential health risks.

Public health officials emphasize that the benefits of fluoride in preventing cavities far outweigh any theoretical risks. Tooth decay remains one of the most common chronic diseases in both children and adults, leading to pain, infection, and costly dental treatments. Fluoridation reduces these risks by strengthening tooth enamel and reducing the ability of bacteria to produce acid that erodes teeth.

The study’s authors caution that while their findings are robust, ongoing monitoring of fluoride exposure remains important. They recommend further research to explore any potential effects at extremely high levels of exposure or in populations with unique dietary patterns. For now, the evidence supports the continued use of fluoridated water as a safe and effective public health measure.

The World Health Organization (WHO) endorses fluoride as a safe and beneficial additive to drinking water when used at recommended levels. The organization notes that the benefits of fluoride in reducing dental caries are well-documented and outweigh potential risks when properly managed.

What You Need to Know

  • Source: Healthline
  • Published: May 16, 2026 at 21:16 UTC
  • Category: Health
  • Topics: #health · #wellness · #medicine · #fluoride · #drinking-water-has · #effect

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Curated by GlobalBR News · May 16, 2026

🇧🇷 Resumo em Português

Um estudo internacional de grande porte acaba de derrubar um dos principais mitos que alimentavam a polêmica sobre a presença de flúor na água potável brasileira. Contrariando receios de que o mineral pudesse prejudicar o desenvolvimento intelectual de crianças ou a cognição de adultos mais velhos, a pesquisa não encontrou nenhuma relação entre o consumo de água fluoretada e a queda do QI ou declínio cognitivo.

Publicado em periódico de prestígio, o estudo analisou dados de milhares de participantes ao longo de anos e reafirmou, ainda, a eficácia do flúor na prevenção de cáries — benefício já conhecido e defendido pela Organização Mundial da Saúde (OMS). No Brasil, onde a fluoretação da água é obrigatória desde 1974 e atinge mais de 70% da população, a notícia chega como alívio para gestores públicos e especialistas em saúde bucal, que temiam retrocessos em políticas de prevenção. A polêmica, no entanto, não deve desaparecer: grupos contrários à medida prometem continuar questionando a segurança do flúor, exigindo mais estudos e fiscalização rigorosa.

Agora, a expectativa é de que o governo federal e as secretarias estaduais de saúde reforcem campanhas de conscientização sobre os benefícios comprovados da fluoretação, garantindo que a população continue protegida sem abrir espaço para desinformação.

🇪🇸 Resumen en Español

Un estudio científico de gran envergadura ha cerrado el debate: el agua fluorada no afecta negativamente al coeficiente intelectual de los niños ni al rendimiento cognitivo de los adultos mayores. La investigación, publicada en una de las revistas médicas más prestigiosas, desmonta uno de los mitos más extendidos en torno a los posibles riesgos de esta práctica, que sin embargo sigue generando controversia en algunos sectores.

El estudio, realizado con una muestra representativa de miles de participantes, reafirma además que el flúor en el agua potable sigue siendo una herramienta clave en la prevención de caries, especialmente en poblaciones con acceso limitado a pasta dental o revisiones odontológicas. Para los hispanohablantes, este hallazgo es relevante, ya que países como España o México aún registran altas tasas de caries infantil, donde el fluoruro, ya sea en el agua o en otros formatos, podría seguir siendo una solución efectiva y segura. La evidencia ahora es clara: el miedo a sus supuestos efectos neurológicos carece de fundamento, mientras que su beneficio dental sigue respaldado por la ciencia.