The three levels of preventive measures for osteoporosis are as follows: 1. primary prevention: when there is no osteoporosis, maintain good bone density to avoid the occurrence of osteoporosis when there is a decrease in bone density; 2. secondary prevention: when there is osteoporosis, maintain good bone density and prevent the occurrence of fracture through anti-bone resorption drugs, bone-forming drugs, and interventions on lifestyle, such as increasing muscle strength and preventing falls; 3. tertiary prevention: when there is already a fracture, actively treat osteoporosis, otherwise the patient’s risk of re-fracture is 3-5 times higher than that of non-fracture, and even within 10 years will also increase the risk of death.