Fluorine Sources

Water fluoridation

The major source of dietary fluoride in the U.S. diet is drinking water. When water is fluoridated, it is adjusted to between 0.7 and 1.2 milligrams (mg) of fluoride per liter or 0.7-1.2 ppm. This concentration has been found to decrease the incidence of dental caries while minimizing the risk of dental fluorosis and other adverse effects. Approximately 62% of the U.S. population consumes water with sufficient fluoride for the prevention of dental caries. The average fluoride intake for adults living in fluoridated communities ranges from 1.4 to 3.4 mg/day. Because well water can vary greatly in its fluoride content, people who consume water from wells should have the fluoride content of their water tested by the local water district or health department. Water fluoride testing may also be warranted in households that use home water treatment systems. While water softeners are not thought to change water fluoride levels, reverse osmosis systems, distillation units, and some water filters have been found to remove significant amounts of fluoride from water. However, Brita-type filters do not remove fluoride.

Food sources

The fluoride content of most foods is low (less than 0.05 mg/100 grams). Rich sources of fluoride include tea, which concentrates fluoride in its leaves, and marine fish that are consumed with their bones (e.g., sardines). Foods made with mechanically separated (boned) chicken, such as canned meats, hot dogs, and infant foods also add fluoride to the diet. Foods generally contribute only 0.3-0.6 mg of the daily intake of fluoride. An adult male residing in a community with fluoridated water has an intake range from 1-3 mg/day. Intake is less than 1 mg/day in non-fluoridated areas. The table below provides a range of fluoride contents for a few fluoride-rich foods.

Food	Serving	Fluoride (mg)
Tea	100 ml (3.5 fluid ounces)	0.1-0.6
Canned sardines (with bones)	100 g (3.5 ounces)	0.2-0.4
Fish (without bones)	100 g (3.5 ounces)	0.01-0.17
Chicken	100g (3.5 ounces)	0.06-0.10

Fluoride supplements

Fluoride supplements are available only by prescription, and are intended for children living in areas with low water fluoride concentrations for the purpose of bringing their intake to approximately 1 mg/day. The American Dental Association recommends fluoride supplements for those children living in areas with suboptimal water fluoridation. The supplemental fluoride dosage schedule in the table below was recommended by the American Dental Association, the American Academy of Pediatric Dentistry, and the American Academy of Pediatrics. It requires knowledge of the fluoride concentration of the local drinking water, as well as other possible sources of fluoride intake. For more detailed information regarding fluoride and the prevention of dental caries, visit the American Dental Association Web site.

American Dental Association Fluoride Supplement Schedule

Age	Fluoride ion level in drinking water (ppm)*
Age	< 0.3 ppm	0.3-0.6 ppm	> 0.6 ppm
Birth - 6 months	None	None	None
6 months - 3 years	0.25 mg/day**	None	None
3 years - 6 years	0.50 mg/day	0.25 mg/day	None
6 years -16 years	1.0 mg/day	0.50 mg/day	None

* 1.0 part per million (ppm) = 1 milligram/liter (mg/L)
** 2.2 mg sodium fluoride contains 1 mg fluoride ion.

Toothpaste

Fluoridated toothpastes add considerably to fluoride intake of children, especially young children who are more likely to swallow them. Researchers estimate that children under 6 years of age ingest an average of 0.3 mg of fluoride from toothpaste with each brushing. Children under the age of 6 years who ingest more than 2 or 3 times the recommended fluoride intake are at increased risk of a white speckling or mottling of the permanent teeth, known as dental fluorosis. The major source of excess fluoride intake in this age group comes from swallowing fluoride-containing toothpaste. In order to prevent dental fluorosis while providing optimum protection from tooth decay, it is recommended that parents supervise children under 6 years of age while brushing with fluoridated toothpaste. In addition to discouraging the swallowing of toothpaste, children should be encouraged to use no more than a pea-size application of toothpaste, and to rinse their mouths with water after brushing.

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