Abstract
OBJECTIVES: To assess the relationships between longitudinal fluoride intakes and bone densitometry outcomes in young adults. METHODS: Data were analyzed from the Iowa Fluoride Study and Iowa Bone Development Study, which followed 1,882 infants from birth in 1992. Daily fluoride intakes were assessed using detailed questionnaires sent every 1.5-6 months, and multi-row detector computed tomography (MDCT) scans of distal tibia were obtained from 330 participants aged 23 years. Sex-specific bivariate and multivariable associations with MDCT outcomes were examined using linear regression. Because of the multiple statistical analyses being conducted, p-values < 0.01 were considered statistically significant. RESULTS: In fully adjusted analyses, no statistically significant (p < 0.01) or suggestive (0.01 < p < 0.05) associations were found between period-specific or cumulative fluoride intake and bone measures for either sex, although there were suggestive positive relationships in unadjusted analyses. CONCLUSIONS: Longitudinal fluoride intakes had little association with bone measures at age 23. As there were no adverse effects from fluoride intake on bone health in young adults, results support the continued use of fluorides, particularly community water fluoridation is the most cost-effective method of dental caries prevention.