Vitamin D insufficiency in internal medicine residents

Medical residents may be vulnerable to low vitamin D status because of long work hours and lack of sun exposure. We conducted a prospective cohort study to measure serum 25-hydroxyvitamin D concentrations among internal medicine residents, document seasonal variation in vitamin D status, and assess risk factors for inadequate vitamin D stores. Dietary intake of calcium and vitamin D, lifestyle characteristics, and serum concentrations of 25(OH)-vitamin D and intact parathyroid hormone (iPTH) were measured in 35 resident volunteers before and after the winter season. A total of 63-69% of medical residents consumed