Osteopenia refers to bone mineral density (BMD) that is lower than normal peak BMD but not low enough to be classified as osteoporosis. Bone mineral density is a measurement of the level of minerals in the bones, which shows how dense and strong they are. If your BMD is low compared to normal peak BMD, you are said to have osteopenia. Having osteopenia means there is a greater risk that, as time passes, you may develop BMD that is very low compared to normal, known as osteoporosis.
What causes osteopenia?
Bones naturally become thinner as people grow older because, beginning in middle age, existing bone cells are reabsorbed by the body faster than new bone is made. As this occurs, the bones lose minerals, heaviness (mass), and structure, making them weaker and increasing their risk of breaking. All people begin losing bone mass after they reach peak BMD at about 30 years of age. The thicker your bones are at about age 30, the longer it takes to develop osteopenia or osteoporosis.
Some people who have osteopenia may not have bone loss. They may just naturally have a lower bone density. Osteopenia may also be the result of a wide variety of other conditions, disease processes, or treatments. Women are far more likely to develop osteopenia and osteoporosis than men. This is because women have a lower peak BMD and because the loss of bone mass speeds up as hormonal changes take place at the time of menopause. In both men and women, the following things can contribute to osteopenia:
Eating disorders or metabolism problems that do not allow the body to take in and use enough vitamins and minerals
Chemotherapy, or medicines such as steroids used to treat a number of conditions, including asthma
Exposure to radiation
Having a family history of osteoporosis, being thin, being white or Asian, getting limited physical activity, smoking, regularly drinking cola drinks, and drinking excessive amounts of alcohol also increase the risk of osteopenia and, eventually, osteoporosis.
Osteopenia is treated by taking steps to keep it from progressing to osteoporosis and, for a few people, by taking medicine. Lifestyle changes can help reduce the bone loss that leads to osteopenia and osteoporosis.
What you eat is very important to bone development. Calcium is the most critical mineral for bone mass. Your best sources of calcium are milk and other dairy products, green vegetables, and calcium-enriched products.
Your doctor may also want you to take a calcium supplement, often combined with vitamin D. Vitamin D helps your body absorb calcium and other minerals. It is found in eggs, salmon, sardines, swordfish, and some fish oils. It is added to milk and can be taken in calcium and vitamin supplements. In addition to what you take in from food, your body makes vitamin D in response to sunlight.
Exercise is important for having strong bones, because bone forms in response to stress. Weight-bearing exercises such as walking, hiking, and dancing are all good choices. Adding exercise with light weights or elastic bands can help the bones in the upper body. Talk to your doctor or a physical therapist about starting an exercise program.
In addition to diet and exercise, quitting smoking and avoiding excessive use of alcohol and cola will also reduce your risk of bone loss.
There are medicines for treating bone thinning. But these are more commonly used if you have progressed past osteopenia to the more serious condition of osteoporosis. Medicines that may be used for osteopenia include bisphosphonates, raloxifene, and hormone replacement. For more information on these medicines, see the topic Osteoporosis.
How can osteopenia be prevented?
Whether you will tend to develop osteopenia is, in part, already determined. Things like whether you have any family members who have had osteoporosis or osteopenia, whether you have chronic asthma that requires you to take steroids, and how much calcium and vitamin D you got while you were growing up are beyond your control now. But if you are a young adult or if you are raising children, there are things you can do to help develop strong bones and help slow down osteopenia and prevent osteoporosis.
Your bones don’t reach their greatest density until you are about 30 years old, so for children and people younger than 30, anything that helps increase bone density will have long-term benefits. To maximize bone density, make sure you get plenty of calcium and vitamin D through your diet and by spending a little time in the sun, get weight-bearing exercise on a regular basis, don’t smoke, and avoid cola and excessive alcohol. If you have children, teach them to eat healthy, get regular exercise, and avoid smoking and alcohol. Also, get them to play a little in the sunshine to help their bodies make more vitamin D. Talk with your doctor about how much and what sources of vitamin D are right for your child.
If you’re older than 30, it’s still not too late to make these lifestyle changes. A balanced diet and regular exercise will help slow the loss of bone density, delay osteopenia, and delay or prevent osteoporosis.