Osteoporosis, or porous bone, is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to bone fragility and an increased risk of fractures of the hip, spine, and wrist. Men as well as women are affected by osteoporosis, a disease that can be prevented and treated. In the United States, more than 53 million people either already have osteoporosis or are at high risk due to low bone mass.
What Is Bone?
Bone is living, growing tissue. It is made mostly of collagen, a protein that provides a soft framework, and calcium phosphate, a mineral that adds strength and hardens the framework.
This combination of collagen and calcium makes bone both flexible and strong, which in turn helps bone to withstand stress. More than 99 percent of the body’s calcium is contained in the bones and teeth. The remaining 1 percent is found in the blood.
Throughout one’s lifetime, old bone is removed (resorption) and new bone is added to the skeleton (formation). During childhood and teenage years, new bone is added faster than old bone is removed. As a result, bones become larger, heavier, and denser. Bone formation outpaces resorption until peak bone mass (maximum bone density and strength) is reached around age 30. After that time, bone resorption slowly begins to exceed bone formation.
For women, bone loss is fastest in the first few years after menopause, and it continues into the postmenopausal years. Osteoporosis—which mainly affects women but may also affect men—will develop when bone resorption occurs too quickly or when replacement occurs too slowly. Osteoporosis is more likely to develop if you did not reach optimal peak bone mass during your bone-building years.
Certain risk factors are linked to the development of osteoporosis and contribute to an individual’s likelihood of developing the disease. Many people with osteoporosis have several risk factors, but others who develop the disease have no known risk factors. Some risk factors cannot be changed, but you can change others.
Risk factors you cannot change:
- Gender. Your chances of developing osteoporosis are greater if you are a woman. Women have less bone tissue and lose bone faster than men because of the changes that happen with menopause.
- Age. The older you are, the greater your risk of osteoporosis. Your bones become thinner and weaker as you age.
- Body size. Small, thin-boned women are at greater risk.
- Ethnicity. Caucasian and Asian women are at highest risk. African American and Hispanic women have a lower but significant risk.
- Family history. Fracture risk may be due, in part, to heredity. People whose parents have a history of fractures also seem to have reduced bone mass and may be at risk for fractures.
Risk factors you can change:
- Sex hormones. Abnormal absence of menstrual periods (amenorrhea), low estrogen level (menopause), and low testosterone level in men can bring on osteoporosis.
- Anorexia nervosa. Characterized by an irrational fear of weight gain, this eating disorder increases your risk for osteoporosis.
- Calcium and vitamin D intake. A lifetime diet low in calcium and vitamin D makes you more prone to bone loss.
- Medication use. Long-term use of certain medications, such as glucocorticoids and some anticonvulsants can lead to loss of bone density and fractures.
- Lifestyle. An inactive lifestyle or extended bed rest tends to weaken bones.
- Cigarette smoking. Smoking is bad for bones as well as the heart and lungs.
- Alcohol intake. Excessive consumption of alcohol increases the risk of bone loss and fractures.
To reach optimal peak bone mass and continue building new bone tissue as you age, you should consider several factors.