Many factors can put someone at risk for the bone-weakening conditions of osteopenia and the more serious osteoporosis, says endocrinologist Jennifer Kelly, DO. Among them are a woman‘s postmenopausal drop in estrogen, a sedentary lifestyle, smoking and endocrine diseases such as hyperthyroidism, says Kelly, clinical director of the bone density unit at Upstate‘s Joslin Diabetes Center. She also describes the lifestyle changes and drugs recommended to treat osteoporosis.