Copyright © 2012
Oregon Osteoporosis Center
All rights reserved
What is Osteoporosis?
Osteoporosis is a disorder in which the calcium content of the skeleton is gradually depleted until the bone becomes fragile and more susceptible to fracture. During childhood and adolescence, calcium is deposited in bones as they grow. This process continues until peak bone mass is reached at about age thirty. From then on, bone loss occurs gradually and progressively in both men and women for the remainder of our lives. In women, there is an acceleraton of bone loss in the first few years after menopause. This period of rapid bone loss is related to the deficiency of estrogen (female hormone) which occurs at that time, and is an important reason for the increased frequency of osteoporosis in women compared to men.
Osteoporosis can occur due to a decrease in the amount of bone made during the growth years (low peak bone mass), or to the increased rate of bone loss which happens in adulthood, or due to both. Peak bone mass is mainly determined by heredity. Individuals with a family history of osteoporosis frequently have lower than average bone mass, even as young adults. Peak bone mass may also be influenced by calcium intake and the amount of exercise during the growth years. Many factors can influence the rate of bone loss. These include the age at which menopause occurs, calcium intake, level of physical activity, lifestyle factors such as the use of alcohol and tobacco, and a variety of medical problems which can interfere with bone health, including low male hormone levels in men. All of these risk factors for osteoporosis increase the normal rate of bone loss. When we measure bone density, we determine the combined effects of peak bone mass and the subsequent loss of bone.
According to the National Institutes of Health, more than 28 million Americans are affected by osteoporosis today, and the disease leads to a million and a half fractures each year in this country. One out of every two women and one in eight men over 50 will have an osteoporosis-related fracture in their lifetime.
Copyright ©2012 Oregon Osteoporosis Center. All rights reserved.