Vitamin D Status in Males in Jerusalem Area and Its Correlation to Parathyroid Hormone (PTH) Level and Bone Mineral Density

Because of its high sun exposure, Israel was traditionally supposed to be protected from vitamin D deficiency, and the country food products hardly contain vitamin D supplements. However the Jerusalem ultra-Orthodox population, which constitutes a significant fraction of the city population, is at risk of developing vitamin D deficiency due to low sun exposure, as consequence of its dressing code covering most of the body and very limited time of outside activities. The investigators aim is to check whether vitamin D deficiency is found more frequently in the ultra-Orthodox male population in comparison to a non-ultra-Orthodox male population, and to study its eventual consequences. Correlation between vitamin D levels and PTH levels will be examined, according to age and to creatinine levels. Bone mineral density (BMD) will be evaluated in 2 selected subgroups of subjects (with lowest and highest vitamin D levels), and re-evaluated after 6 months of vitamin D supplementation in vitamin D-deficient subjects. An increase in BMD within 6 months would suggest osteomalacia as the main cause of low BMD in these subjects.