Background: Randomized controlled trials have shown that high fluoride doses increases both bone mineral density and skeletal fragility. The consequences of long-term low dose exposure to fluoride, primarily via drinking water, on bone health among the general public is however not clear. In the present study, we assessed associations of fluoride in urine or in beverages and diet with bone health in postmenopausal women.
Methods: We used the population-based prospective Swedish Mammography Cohort- Clinical, encompassing 4306 postmenopausal women (aged 56-85), residing in Uppsala county, Sweden, with drinking water fluoride ?1 mg/L. Fluoride was measured in urine (mg/g creatinine), and estimated from diet and drinking water (mg/day) at baseline. Hip and spine bone mineral density was measured at baseline using dual-energy X-ray absorptiometry. Incident cases of fractures were ascertained through linkage to the Swedish National Patient Register during 9.3 years of follow-up. Associations of exposures (comparing tertiles) with outcomes were assessed using regression analyses.
Results: The mean urinary fluoride was 1.2 mg/g creatinine (+/- standard deviation 1.9) and the mean dietary fluoride was 2.2 mg/day (+/-0.9). 78% of the dietary intake originated from water-based beverages. During 40,200 person-years of follow-up, 850, 353 and 187 cases of any fractures, osteoporotic fractures and hip fractures were ascertained, respectively. In the cross-sectional assessment, dietary fluoride, but not urinary fluoride, was associated with a 1-2% higher baseline bone mass at the hip and spine. Both dietary and urinary fluoride was prospectively associated with increased risk of hip fractures, hazard ratios for highest vs lowest tertile 1.59 (95% confidence interval, CI 1.10-2.31) and 1.50 (95% CI 1.04-2.15), respectively.
Conclusion: A high consumption of water and water-based beverages with a fluoride concentration around 1 mg/L, may increase the risk of hip fracture in older women.
*Abstract in the Conference Abstract E-Posters at http://fluoridealert.org/wp-content/uploads/isee2020.abstract-e-posters.pdf
E. Helte, Karolinska Institutet, Stockholm, SWEDEN,
C. Donat Vargas, Universidad Autónoma de Madrid, Madrid, SPAIN
M. Kippler, Karolinska Institutet, Stockholm, SWEDEN,
A. Wolk, Karolinska Institutet, Stockholm, SWEDEN,
K. Michaelsson, Uppsala University, Uppsala, SWEDEN.
A. Akesson, Karolinska Institutet, Stockholm, SWEDEN,