Fluoride Intake from Foods and Beverages in Japanese Children

Objective: The main aim of this study was to measure the amount of fluoride intake (F-intake) from foods and beverages in Japanese children in view of estimating the adequate intake (AI) of fluoride, which has not been decided in Japan. Another aim was to assess how fluoride concentration of water can reflect on F-intake in Japanese dietary habits. Methods: We enrolled 54 children aged 1-12 years living in two neighboring areas with different fluoride concentrations in drinking water. Thirty-two out of 54 children lived in an area with a community water fluoride concentration of 0.56 ppm (moderate fluoride area: MFA) while 22 children lived in an area where fluoride concentration in the community water was less than 0.1ppm (low fluoride area: LFA). To measure the fluoride intake, foods and beverages were collected by a duplicate-diet technique from their families. The fluoride concentrations in each sample were measured by difussion technique of Taves (1968) and electrode technique. Results: The mean daily F-intake of children living in MFA and LFA were 0.025 mg/day/kg (body weight) and 0.015 mg/day/kg, respectively. There was a statistically significant difference in F-intake (p<0.001) between children in the MFA and in the LFA. When compared by category of materials, such as boiled rice, side dishes and beverages, the mean daily F-intake from rice and beverages only in the MFA was shown to be significantly higher (p<0.01) than that in the LFA. Conclusions: These results suggest that fluoride concentration in drinking water can reflect on total F-intake. However, the mean daily F-intake of children who even lived in MFA was almost 50% lower than the AI defined in the United States (0.05mgF/day/kg). This work was supported by a Grant-in-Aid from the Ministry of Health, Labour and Welfare of Japan (H12-Iryo-003)