Osteoporosis is the thinning of bone tissue and loss of bone
density over time
General information about Osteoporosis
Osteoporosis is a serious public health problem. Some 28 million people in the United
States are affected by this potentially debilitating disease, which is responsible for 1.5
million fractures (broken bones) annually. These fractures, which are often the first sign
of the disease, can affect any bone, but the most common locations are the hip, spine, and
wrist. Breaks in the hip and spine are of special concern because they almost always
require hospitalization and major surgery, and may lead to other serious consequences,
including permanent disability and even death.
Information on how Osteoporosis developes
To understand osteoporosis, it is helpful to understand the basics of bone formation.
Bone is living tissue that's constantly being renewed in a two-stage process (resorption
and formation) that occurs throughout life. In the resorption stage, old bone is broken
down and removed by cells called osteoclasts. In the formation stage, cells called
osteoblasts build new bone to replace the old. During childhood and early adulthood, more
bone is produced than removed, reaching its maximum mass and strength by the mid-30s.
After that, bone is lost at a faster pace than it's formed, so the amount of bone in the
skeleton begins to slowly decline. Most cases of osteoporosis occur as an acceleration of
this normal aging process. That's referred to as primary osteoporosis. The condition can
also be caused by other disease processes or prolonged use of certain medications that
result in bone loss--if so, it's called secondary osteoporosis.
Information on how Osteoporosis occurs
Osteoporosis occurs most often in older people and in women after menopause. It affects
nearly half of all those, men and women, over the age of 75. Women, however, are five
times more likely than men to develop the disease. They have smaller, thinner bones than
men to begin with, and they lose bone mass more rapidly after menopause (usually around
age 50), when they stop producing a bone-protecting hormone called estrogen. In the five
to seven years following menopause, women can lose about 20% of their bone mass. By age 65
or 70, though, men and women lose bone mass at the same rate. As an increasing number of
men reach an older age, there's more awareness that osteoporosis is an important health
issue for them as well.
Researchers estimate that about 20% of American women over the age of 50 have
osteoporosis. In addition, another 30% of them have osteopenia, which is abnormally low
bone density that may eventually deteriorate into osteoporosis, if not treated.
About half of all women over the age of 50 will suffer a fracture of the hip, wrist, or
Women who are white, especially those with a family history of osteoporosis, have a
greater risk of developing osteoporosis. Other risk factors include smoking, eating
disorders, low body weight, low amount of calcium in the diet, heavy alcohol consumption,
early menopause, absence of menstrual periods (amenorrhea), and use of certain
medications, such as steroids and anticonvulsants