Too much fluoride increases risk of mild fluorosis in kids

Oct 24, 2010

Young children who consume substantial amounts of fluoride through infant formula and other beverages mixed with fluoridated water or by swallowing fluoride toothpaste are at increased risk of developing mild enamel fluorosis, according to research published in the October issue of the Journal of the American Dental Association (Vol. 141:10, pp. 1190-1201) and supported by the National Institute of Dental and Craniofacial Research.

But children can continue using fluoridated water and fluoride toothpaste because fluoride has been proven to prevent tooth decay, and mild fluorosis does not negatively affect dental health or quality of life, the study authors found.

Researchers from the University of Iowa recruited mothers of newborn infants from eight Iowa hospital postpartum wards between 1992 and 1995 for their children's participation in what would become known as the Iowa Fluoride Study, an investigation of dietary and nondietary fluoride exposures, dental fluorosis, and dental cavities. They sent questionnaires to the parents at regular intervals and 630 children underwent visual dental examinations using standardized techniques and portable equipment.

They found that substantial fluoride consumption from beverages with fluoridated water, including infant formula, by children between the ages of 3 to 9 months, elevates a child's risk of developing mild enamel fluorosis. Substantial fluoride consumption from beverages with fluoridated water and from fluoride toothpaste by children between the ages of 16 to 36 months also elevates a child's risk of developing mild enamel fluorosis, the researchers said.

"Nearly all of the fluorosis in our study participants was mild. A recent review of the effects of mild dental fluorosis on oral health-related quality of life concluded that the effect of mild fluorosis was not adverse and could even be favorable," they noted. "This suggests that concerns about mild dental fluorosis may be exaggerated. Therefore, no general recommendations to avoid use of fluoridated water in reconstituting infant formula are warranted."

Mild enamel fluorosis appears as barely noticeable faint white lines or streaks on tooth enamel that may occur when children ingest excess fluoride while their teeth are developing, according to the ADA.

The American Academy of Pediatrics recommends breastfeeding for infants. The researchers also encourage parents to follow recommendations to use small (smear or pea-sized) amounts of fluoridated toothpaste and ensure proper supervision of the child's toothbrushing.