Osteopenia refers to having bone mineral density (BMD) that is below normal levels but not low enough to be classified as osteoporosis.
Having a family history of osteoporosis, being thin, being Caucasian or Asian, lack of adequate physical activity, smoking, and drinking excessive amounts of alcohol also increase the risk of osteopenia and, eventually, osteoporosis.
Until you actually break a bone, osteopenia has no defining symptoms. You notice no pain as the bone becomes thinner, although the risk of breaking a bone increases as the bone becomes less dense.
Osteopenia is diagnosed with a bone mineral density test, the most accurate being a dual-energy X-ray absorptiometry (DEXA) scan. DEXA is a form of X-ray that can detect as little as 2% of bone loss per year. A standard X-ray is not helpful in diagnosing osteopenia due to lack of sensitivity. .