The cause of osteoporosis isn’t fully understood. What is known is that the condition involves a disruption in the bone-building process. Hormonal factors—namely, the hormone changes that occur during menopause in women or natural aging in men—also play a significant role in the development of osteoporosis.
Age is the primary risk factor of osteoporosis. Under normal conditions in the body, new bone is made and old bone is broken down in a consistant ratio that results in increased deposits of new bone and bone density. Peak bone mass is generally reached at approximately age 25 to 30. Peak bone mass is primarily determined by genetic factors including race and gender. Until the approximate age of 30, your body forms new bone faster than it can break down old bone. After age 35, both men and women begin to lose peak bone mass at a rate of 0.5 to 1% per year. This means that bone is broken down faster than it’s being built. Gradually, this results in a loss of bone mass. A small loss of bone mass is normal. However, in people with osteoporosis, there is a greater rate of bone loss. Bones become porous and fragile, and therefore, more likely to fracture.
The hormone estrogen appears to suppress osteoclasts, the cells in your body that break down and absorb bone. When women reach menopause, estrogen levels decline, which triggers a rapid loss of bone mineral density. The accelerated rate of bone loss after menopause is most prominent in the certain areas, such as the spine, where the rate of loss can be 3 to 5% per year during the 10 years after menopause.This deficit can lead to osteoporosis.