Decreased bone mass, known as osteoporosis, can be treated with vitamin D supplementation, calcium, and bone metabolism-modifying drugs. 1. Vitamin D supplementation: Vitamin D accelerates intestinal absorption of calcium and reduces renal excretion of calcium, increasing the body’s utilization of calcium. Supplementation of calcium alone may not only aggravate the gastrointestinal burden, but also have a lower absorption rate. 2. Calcium supplements: Calcium tablets and other supplements available on the market, such as calcium lactate tablets. 3. Bone metabolism regulating drugs: such as calcitonin and osteotriol. Osteoporosis is a common cause of bone fracture in the elderly, and bed-ridden elderly with bone fracture for a long time will increase the probability of thrombotic diseases in the elderly. Therefore, it is important to prevent and treat osteoporosis in the elderly. The dosage of the drug should follow the doctor’s instructions.