Association of total calcium and dietary protein intakes with fracture risk in postmenopausal women: The 1999–2002 National Health and Nutrition Examination Survey (NHANES)

Abstract

Objective We examined the associations of total calcium intake (TCI) and dietary protein intake (DPI) with risk of fracture. Methods A total of 2006 postmenopausal women ≥50 y of age who were measured in the 1999–2002 National Health and Nutrition Examination Survey were included in the study. Weighted mean TCI and DPI and percentage of distributions of selected characteristics were estimated by TCI category and fracture status. Multivariate logistic regression models were used to assess the effect of TCI and DPI on risk of fracture. Results Thirteen percent of participants reported a fracture history, of whom 17.8% consumed a total of ≥1200 mg of calcium per day and 23.8% consumed <400 mg/d. TCI was not associated with fracture risk when controlling for all selected covariates. In women who consumed <46 g/d of dietary protein, those with a TCI ≥1200 mg/d had a significantly higher risk of fracture than those with the lowest TCI (adjusted odds ratio 5.98, 95% confidence interval 1.15–31.13), whereas in women who consumed >70 g/d of dietary protein, those with a TCI ≥1200 mg/d had an insignificant lower risk of fracture (adjusted odds ratio 0.69, 95% confidence interval 0.20–2.39). Conclusion TCI is not associated with risk of fracture among postmenopausal women. Adequate TCI in the presence of inadequate DPI may not be protective against fractures. Optimal proportion of TCI and DPI warrants further investigation among older women.