Public water fluoridation, once a celebrated preventive dentistry milestone, is increasingly being reevaluated in light of current scientific, ethical, and policy considerations. While initially justified based on data suggesting systemic benefits from ingestion, current evidence demonstrates fluoride’s primary anticaries mechanism is topical, not systemic. Simultaneously, recent studies have linked fluoride ingestion—even at levels considered safe (0.7 mg/L) by the U.S. Department of Health and Human Services (HHS)—to neurodevelopmental harm, endocrine disruption, and musculoskeletal risks. This article presents a review of the scientific literature addressing fluoride’s mechanisms of action, its systemic risks, and the ethical challenges posed by involuntary mass medication. Based on recent epidemiological findings, policy developments, and bioethical principles, the continued practice of public water fluoridation appears scientifically outdated and ethically untenable.

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