Osteoporosis occurs due to weak and fragile bones. Those who have osteoporosis are more prone to fractured bones, especially in the hip, spine and wrist. You should try to build strong bones in earlier stages for which adequate calcium intake is essential. This will help bones remain strong later in life. Millions of people across the globe are affected by osteoporosis and many more are developing osteoporosis as our population ages. Osteoporosis affects more women than men. Osteoporosis occurs over a long period of time. A person with osteoporosis may easily get a fracture. The disease in advanced stages may bring more damage. The major cause of osteoporosis is lack of hormones. Lack of estrogen in women and androgen in men may cause osteoporosis. Menopause and lower estrogen levels increase the risk of osteoporosis. Other factors include inadequate intake of calcium and vitamin D, and other age-related changes in the body. It is reported that the symptoms of osteoporosis may vary from individual to individual.