Water fluoridation

Water fluoridation is the controlled addition of <a href="/facts/Fluoride/LpqNMzwa">fluoride</a> to <a href="/facts/Public_water_supply/1UuexMtl">public water supplies</a> to reduce <a href="/facts/Tooth_decay/trECbk2z">tooth decay</a>. Fluoridated water maintains fluoride levels effective for cavity prevention, achieved naturally or through supplementation. In the mouth, fluoride slows <a href="/facts/Tooth_enamel/ffUMmssl">tooth enamel</a> <a href="/facts/Demineralization_(physiology)/StwHQBgq">demineralization</a> and enhances <a href="/facts/Remineralization/jqr6FrfB">remineralization</a> in early-stage cavities. <a href="/facts/Defluoridation/75QqRvWs">Defluoridation</a> is necessary when natural fluoride exceeds recommended limits. The <a href="/facts/World_Health_Organization/YNN3bgug">World Health Organization</a> (WHO) recommends fluoride levels of 0.5–1.5 mg/L, depending on <a href="/facts/Climate/f57XrNFU">climate</a> and other factors. In the U.S., the recommended level has been 0.7 mg/L since 2015, lowered from 1.2 mg/L. <a href="/facts/Bottled_water/rYhTeJLQ">Bottled water</a> often has unknown fluoride levels.
Tooth decay affects 60–90% of schoolchildren worldwide. Fluoridation reduces cavities in children, with <a href="/facts/Cochrane_(organisation)/UlmdJ1H8">Cochrane</a> reviews estimating reductions of 35% in baby teeth and 26% in permanent teeth when no other fluoride sources are available, though efficacy in adults is less clear.[needs update] In Europe and other regions, declining decay rates are attributed to <a href="/facts/Topical_fluoride/PKPff9ml">topical fluorides</a> and alternatives like salt fluoridation and <a href="/facts/Nano-hydroxyapatite/SqcXuXVQ">nano-hydroxyapatite</a>.
The United States was the first country to engage in water fluoridation, and 72% of their population now drinks fluoridated water as of 2022. Globally, 5.4% of people receive fluoridated water, though its use remains rare in Europe, except in <a href="/facts/Ireland/35vYxXdP">Ireland</a> and parts of Spain. The <a href="/facts/WHO/YNN3bgug">WHO</a>, <a href="/facts/FDI_World_Dental_Federation/oeamhFpU">FDI World Dental Federation</a>, and <a href="/facts/Centers_for_Disease_Control_and_Prevention/NmoJNDV5">Centers for Disease Control and Prevention</a> endorse fluoridation as safe and effective at recommended levels. Critics question its risks, efficacy, and ethical implications.
Recent <a href="/facts/Systematic_reviews/dGvq3BGx">systematic reviews</a> suggest an association between higher <a href="/facts/Fluoride/LpqNMzwa">fluoride</a> exposure and lower <a href="/facts/IQ/rozfcXsk">IQ</a> in children. These findings remain debated among experts and public health organizations.

Water fluoridation open-in-new

Water fluoridation