Your Healthy Bones Action Plan
Why Your Bones Change -- and When
Though we think of bones as being static and unchanging, they aren't. They are composed of living tissue that is constantly in flux. Two types of cells that help with bone formation are osteoblasts, which make new bone tissue, and osteoclasts, which break down current bone tissue in a process known as remodeling. To build and maintain bone, your body needs a steady supply of calcium (along with Vitamin D to maximize calcium absorption) and estrogen. Bones also need weight-bearing exercise, such as walking, strength training, or jogging. But exercise alone won't keep bones healthy, as Koontz learned.
While we're young, this process ticks along smoothly, with the body building bone more rapidly than it loses it, till we reach our peak bone mass in our mid-20s. Then the scenario changes and we gradually lose bone faster than it can be replaced. When estrogen levels fluctuate during perimenopause (it typically starts between ages 45 and 47) then plummet after menopause (about 51), bone loss accelerates.
That's why we need to be vigilant about keeping the bone we have. Indeed, the only way to prevent osteoporosis is to make bones as strong as possible when we're young and keep them healthy as we get older, says Bess Dawson-Hughes, MD, director of the Bone Metabolism Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, in Medford, Massachusetts. Think of eating well and exercising as making deposits in your bone bank. Surveys show that nine out of 10 women don't get enough calcium to help maintain bone health. And only 40 percent of Americans regularly exercise.
If you've been remiss, you can still start helping yourself now. Case in point: Katy Koontz began taking a prescription bone-building medication as well as a calcium supplement to slow down her bone loss and strengthen the bone she had while continuing to walk five miles a day. Each year her bone density improved slightly. Nearly a decade later, though she still has osteopenia, her doctor is so pleased with her improved bone health that Koontz has returned to the slopes.
Your age and your estrogen level determine which strategies make the most sense for you at each stage of your life. Start by finding your age group (and that of your mother or postadolescent daughter) on the following pages. To protect your kids, see "Strong Bones Start Early."