Osteoporosis, one of the most common bone diseases, causes bones to become weak, brittle and at risk for breaks. Though more common in women, it also affects men.
Bone is living tissue that constantly broken down and re-formed through a two-part process called remodeling. Remodeling consists of resorption, when old bone tissue is broken down, and formation, when new bone tissue is formed.
Osteoporosis occurs when bone removal happens too quickly, replacement too slowly or both. The main cause is age. Remodeling is controlled by hormones that decline with age, including estrogen (in women) and testosterone (in men).
Who's at risk?
- Women - particularly after menopause. Women who experience menopause before age 50 are at even higher risk.
- Caucasians and Asians more than African Americans and Hispanics
- People with a family history of osteoporosis
- Thin, small-boned people
- People who smoke, or drink excessive alcohol
- People with inadequate calcium and vitamin D intake
- People who do not regularly engage in weight-bearing exercise
- Men and women undergoing prolonged steroid therapies
Osteoporosis has been called a "silent" disease because there are few symptoms in its early stages. It cannot be detected by conventional X-ray until 40 percent of bone mass is lost. Fortunately, bone mineral density testing can catch the disease early, but some people don't learn they have osteoporosis until a bone breaks, most commonly in the hip, wrist and spine.