1. Calcium Metabolism and Osteoporosis Program (J.M., R.E.-R., G.E.-H.F.), School of Health Sciences, American University of Beirut, Beirut, Lebanon 113-6044
2. Department of Internal Medicine and Department of Pediatrics (M.N.), School of Medicine, American University of Beirut, Beirut, Lebanon 113-6044
3. Department of Laboratory Medicine (R.V.), University of Toronto, Toronto, Canada M5S 3E2
4. Departments of Nutritional Sciences (R.V., S.K.), University of Toronto, Toronto, Canada M5S 3E2
5. Department of Epidemiology and Population Health (Z.M.), School of Health Sciences, American University of Beirut, Beirut, Lebanon 113-6044