©2006 Publications International, Ltd. Weight-driven exercises are an important bone-building tool.

More than 28 million Americans are at risk for osteoporosis, and more than 10 million already have been diagnosed with this bone-degenerating disease. Women make up an astounding 80 percent of those who are affected by osteoporosis. Though most people associate osteoporosis with older people, the disease strikes young and old alike. But osteoporosis does become much more common as you age -- affecting one in two women over age 50.

Bone Up on Osteoporosis

As you grow your bones get stronger and longer. By the time you reach the age of 20, you've got 98 percent of your bone mass; by the time you reach your thirtieth birthday, your bones are their strongest. If you were able to take a look inside your bones during those peak years, you'd see a hard outer shell and something that looks like a honeycomb on the inside. About 80 percent of your bone mass is that tough, hard outer bone called cortical bone. The rest of your bone make-up is the honeycomb-like material called trabecular bone. After you hit 30, your bone mass begins to decline. Trabecular bone is typically the first to lose critical density, and as you get older, cortical bone mass also declines, but at a slower pace.

Osteoporosis literally means porous bones. That means someone diagnosed with the disease has lost so much density that there's not much there to hold their bones together, putting them at greater risk for bone breaks and fractures. The National Osteoporosis Foundation calls osteoporosis the "silent disease" because there are virtually no symptoms of bone loss. Unless you're aware of the risk factors and take action, you may not know you have the disease until some benign bump on the garage door turns into a fracture.

Because the symptoms are not obvious, it's important to know whether or not you are at risk. Go to the next page to find out if you are a potential candidate for osteoporosis.

For more information on disorders and symptoms related to osteoporosis, try the following links:

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