What is primary osteoporosis?

The vast majority of people with osteoporosis have primary osteoporosis. It is usually a late-onset osteoporosis caused by a lack of estrogen, calcium, and vitamin D. It is characterized by a lack of bone density and weak bones. Women with primary osteoporosis have usually been through menopause and men with primary osteoporosis are usually older too.

David Slovik, MD
Endocrinology Diabetes & Metabolism
The most common form of osteoporosis is primary osteoporosis, which is the result of a normal physiological process, such as menopause or aging.
One manifestation of primary osteoporosis, known as postmenopausal osteoporosis, is the result of a rapid loss of bone associated with the decline in estrogen levels in women during the three to five years preceding menopause, at menopause, and following menopause. Typically, bone loss accelerates in the first few years of menopause and then begins to level off. The effects are most prominent in trabecular bone, which isn't as dense as compact bone. Several factors may contribute to this process. A number of researchers are examining the roles of chemical regulators, such as interleukin-1, interleukin-6, prostaglandin E2, and tumor necrosis factor, which appear to speed up bone resorption by spurring on osteoclasts as estrogen levels decline.
Alternately, primary osteoporosis can result from the cumulative effects of the gradual loss of both trabecular and compact bone that occurs with aging. This variation of the condition develops more slowly than postmenopausal osteoporosis and is usually not apparent until age 75 or later. As with all age-related changes, it probably reflects several factors.
One is the general slowdown in bone formation as you age. Another is a decline in the availability of minerals. With age, the intestines gradually absorb less calcium from food, and the kidneys seem to be less efficient at conserving calcium. Thus, more calcium leaves the body in feces and urine, and less reaches the bloodstream, making it more likely that the body will need to tap the bones' calcium stores.
To make matters worse, most people consume less dietary calcium as they age, further straining the bones' calcium supplies. The body's production of vitamin D frequently drops with age as well. Your skin cells use sunlight to produce a precursor of vitamin D; the liver and kidneys then convert this precursor into active vitamin D. Vitamin D plays a central role in the body's absorption of calcium and in the process of turning calcium into bone. If you don't have enough vitamin D to signal your intestines to absorb calcium, your body will break down bone to get the calcium it needs -- no matter how much calcium you're getting from food or supplements.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.