Fluoride is consumed from foods, fluoridated water, toothpaste, and some dietary supplements. Apart from some teas, most foods do not contain a substantial amount of fluoride. There is no dietary reference intake (DRI) for fluoride, but adults consume less than about 0.5 mg daily. The maximum safe daily dose of fluoride is 4 mg in adult men and 3 mg in women.^[1] In Europe, a number of combination mineral supplements for bone health containing 0.95 mg of fluoride per dose have been on the market for 40 years without reported side effects.^[1]

In community drinking water, the concentration of fluoride to prevent tooth decay ranges between 0.5 and 1.1 mg/L. The US Public Health Service recommends a fluoride concentration of 0.7 mg/L, and the US Environmental Protection Agency set the maximum level as 4 mg/L. The World Health Organization (WHO) guideline recommends 1.5 mg/L fluoride in the drinking water.^[2]