What Causes Osteoporosis?

Osteoporosis occurs when the body fails to form enough new bone, when too much old bone is reabsorbed by the body, or both. Women are at a greater risk than men, especially women who are elderly, thin, or small. Other risk factors include the following:

• Inadequate calcium and vitamin D ingestion
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• Lack of weight-bearing exercises
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• Excessive corticosteroid (for example, prednisone [Deltasone, Meticorten]) use
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• Thyroid problems
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• Bone cancer
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• Postmenopause
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• White or Asian race
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• Cigarette smoking
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• Eating disorders
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• Alcoholism