Osteoporosis, or porous bone, is a disease of progressive bone loss and skeletal deterioration in which bones become fragile and more likely to break, or fracture. The disease often develops unnoticed over many years, with no symptoms or discomfort, until a fracture occurs.

Fractures at the hip, spine, and wrist are most common, although any bone can be affected. Many of these fractures are due to a fall, however, even simple household tasks can produce a fracture of the spine if the bones have been weakened by the disease. These fractures often lead to chronic pain, disability and reduced quality of life.

Fractures due to osteoporosis are common. One in two women and one in four men over age 50 will sustain a bone fracture in their remaining lifetime. For women, the chance of having a fracture is greater than the combined chances of having breast, ovarian and uterine cancer.

Any bone can be affected, but of special concern are fractures of the hip and spine. A hip fracture almost always requires hospitalization and major surgery. It can impair a person’s ability to walk unassisted and may cause prolonged or permanent disability, or even death. Most hip fracture patients who previously lived independently will require help from their family or home care. Spinal or vertebral fractures also have serious consequences, including loss of height, severe back pain, and deformity.

The exact medical causes of osteoporosis are not completely known. However, many of the major factors that can lead to the disease have been identified, and are listed below:

Aging
Everyone loses bone with age. After age 35, the body builds less new bone to replace losses of old bone. In general, the older you are, the lower your total bone mass and the greater your risk for osteoporosis.

Heredity
A family history of fractures; a small, slender body build; fair skin; and a Caucasian or Asian background can increase the risk for osteoporosis. Heredity also may help explain why some people develop osteoporosis early in life.

Nutrition and lifestyle
Poor nutrition, including a low calcium diet, low body weight and a sedentary lifestyle have been linked to osteoporosis, as have smoking and excessive alcohol use.

Medications and other illnesses
Osteoporosis has been linked to some medications, including steroids, and to other illnesses, including some thyroid problems.