Water fluoridation by country

Water fluoridation is the controlled addition of fluoride to a public water supply to reduce tooth decay, and is handled differently by countries across the world.

Water fluoridation is considered very common in the United States, Canada, Ireland, Chile and Australia where over 50% of the population drinks fluoridated water.

Most European countries including Italy, France, Finland, Germany, Sweden, Netherlands, Scotland, Austria, Poland, Hungary and Switzerland do not fluoridate water.

Fluoridated water contains fluoride at a level that is proven effective for preventing cavities; this can occur naturally or by adding fluoride. Fluoridated water creates low levels of fluoride in saliva, which reduces the rate at which tooth enamel demineralizes, and increases the rate at which it remineralizes in the early stages of cavities. Typically, a fluoridated compound is added to drinking water, a process that in the U.S. costs an average of about $1.36 per person-year. Defluoridation is needed when the naturally occurring fluoride level exceeds recommended limits. In 2011, the World Health Organization suggested a level of fluoride from 0.5 to 1.5 mg/L (milligrams per liter), depending on climate, local environment, and other sources of fluoride. Bottled water typically has unknown fluoride levels.