What causes osteoporosis?

From infancy through our late twenties, we add minerals, particularly calcium, to the inner cores of our bones, strengthening them. After the age of 30, we lose more minerals than we add. Osteoporosis affects both men and women as they age, but women lose more bone and begin that loss earlier than men, due to the loss of estrogen with menopause. Estrogen loss leads to bone loss, and bone loss leads to fractures, of the hip, the spine and the wrists.

Heredity and lifestyle can hasten this process. Whites and Asians, tall and thin people, and those with a family history of osteoporosis are at the highest risk. While women develop osteoporosis younger than men, men are not immune. Behavioral factors that increase the risk of osteoporosis and osteoporotic fractures include smoking, alcohol abuse, a diet low in calcium, too little exposure to sunlight (necessary for Vitamin D metabolism and stronger bones) and prolonged inactivity.

A number of diseases, many associated with aging, can also cause osteoporosis. These include kidney failure, cancers, liver disease, Paget's disease, endocrine or glandular diseases, rheumatoid arthritis and gonadal failure (such as from surgical removal of the testes or ovaries). Medications, including steroids, thyroid hormone, seizure drugs and blood thinners, can also cause osteoporosis.