In what food source is the nutrient found?

Fluoridated water is the primary source of fluoride. The fluoride content of food depends upon the fluoride content of the soil in which the food was grown. Some infant formulas that are made or mixed with fluoridated water also contain fluoride. Brewed tea can contain significant amounts of fluoride. The amount depends on the amount of tea used, the water fluoridation concentration, and the brewing time. Fish with edible bones, such as canned salmon, also provides some dietary fluoride. Fluoride mouth rinses and toothpastes are sources of fluoride to the outside of the teeth (topical fluoride).

How does the nutrient affect the body?

Although fluoride helps harden the tooth enamel during the time teeth are developing, the main action of fluoride occurs after the teeth have erupted. Water fluoridation has been found to be effective in preventing dental decay in both children and adults. Topical fluoride is important in preventing tooth decay in already erupted teeth. It does this by helping to prevent the destruction of the tooth enamel by acid in the mouth. It also interferes with the formation of dental plaque.

Fluoride that is eaten is secreted in the saliva and can protect teeth in the same way as topical fluoride. Fluoride supplementation can promote bone building, but early studies in people with osteoporosis have found that the structure of the new bone was abnormal. It was weaker than normal bone and possibly more prone to fracture. Gastrointestinal side effects were also a problem. Researchers are working to find a formulation and dosage regimen that will result in building normal bone.