The number of osteoporosis cases is increasing primarily due to several reasons. Firstly, changes in modern lifestyles, such as lack of exercise and unhealthy eating habits, mean that bones don't get enough exercise and nutrition. Secondly, with an aging population, the proportion of elderly people is increasing, and they are more prone to osteoporosis. Lastly, advances in medical technology allow more people to be diagnosed with osteoporosis, increasing the number of cases. To prevent osteoporosis, it's crucial to maintain a healthy diet and regular exercise.