TUESDAY, Nov. 30, 2004 (HealthDayNews) -- Experts are warning Americans that it's time to bone up on bone health, with a recent U.S. Surgeon General's report estimating that at least half of those over age 50 will suffer osteoporotic fractures by the year 2020.
They stress it's not too late to turn those statistics around, because simple steps in youth and middle age can bring big payoffs in bone strength.
"It's very important to know that our skeletons are sort of like a big house for the body -- and we really do need to maintain it," said Gail Frank, a professor of nutrition at California State University, and a spokeswoman for the American Dietetic Association.
According to Frank, the human body tends to build bone until age 30. "No one wants to think that at 30 they're 'mid-life,' but that's the way it is for bone," she said.
Healthy intakes of nutrients during childhood and young adulthood maximize bone-building potential, she said. But even in those over 30, high levels of dietary calcium and other nutrients slow the gradual loss of bone that comes with age.
"Bone needs what I like to call a 'matrix of nutrients,' " Frank explained. Besides calcium, she listed phosphorous, magnesium, zinc -- "what I call a 'bone soup,' a kind of matrix that supports bone, allows for the creation of enzymes and different proteins needed to keep that bone healthy."
Calcium remains the most important factor in bone-healthy diets, with current U.S. Department of Agriculture guidelines recommending that children consume the equivalent of 2 cups of milk per day, and adults take in the equivalent of 3 cups daily.
"Foods are better than supplements for calcium," Frank added, since calcium retains its integrity better in whole foods than in pill form.
"The analogy I like to use is sandcastles," said Dr. Laura Tosi, an orthopedic surgeon and former chairwoman of the Women's Health Issues Committee at the American Academy of Orthopaedic Surgeons (AAOS).
"If you imagine calcium as being the grains of sand, you've got to build lots of those grains into your castle, or it'll disappear with the first wave," she said. "It's getting that calcium into the bone early on, and keeping it there, that makes it strong."
Then there's vitamin D, which your skin makes naturally whenever it's exposed to UV sunlight.
"Vitamin D is the key that unlocks the door -- it lets your body absorb calcium into the bloodstream," Tosi said. She believes urban, indoor-oriented lifestyles are keeping too many Americans from getting the 15 to 20 minutes of noonday sun that bodies need to build and maintain bone.
"Remember, without vitamin D, you can drink your milk or take your calcium supplement, but it simply goes in your mouth and comes out the other end," Tosi said. "Vitamin D allows calcium to enter the bloodstream and the body as a whole."
Especially for individuals living in northern latitudes, Tosi suggests "going out and doing just a little walk in the sun for 15 to 20 minutes at lunchtime," to boost vitamin D activity.
And she stressed that walking -- or any weight-bearing exercise -- is also crucial to keeping bones strong.
"Bone is a use-it-or-lose-it substance," Tosi said. "If you aren't impact-loading -- walking, etcetera -- bone says 'Oh, I guess I'm not really needed,' and just melts away. So get out there and do a brisk walk for half an hour three or four times a week, or preferably every day. That tells bone to 'stay put.' "
Both experts agreed most younger Americans underestimate their risk for brittle bones in old age.
"They think 'Oh, it's never going to happen to me,' " Tosi said. But in fact, the Surgeon General's report, released in October, found that 34 million Americans over 50 are already at high risk for bone fracture.
And bone fractures, even in youth or middle age, are nothing to take lightly, Tosi said.
"If you have a fracture as a [young] adult, that's a really bad sign," she said. "Whether or not you have low bone density, it declares that you're someone at risk for having far more fractures than other people, becoming disabled and losing your freedom as an older adult."
Current data from the AAOS suggest that "fragility fractures" in adults -- fractures occurring from falls at standing height or less -- are "red flags" that bones aren't as strong as they should be, Tosi said.
And fractures in old age can be even more dangerous. According to the AAOS, one out of every three to four elderly men, and one out of every four to five elderly women, will die within one year of a hip fracture.
Then there's the toll fragile bones take on overall quality of life.
"People need a walker or cane for the rest of their life," said Tosi. "They lose their ability to go to the bank, to the grocery store, meet friends for tea. It's tragic. Those are the things that give life meaning."
But brittle bones are preventable, she stressed. Even in middle age, it's not too late to put the brakes on bone loss.
"It's harder, of course, but luckily our bodies are very forgiving, so get on to it now," she said. "Whatever you've got in that sandcastle -- hold on to it."
More information
For more on bone loss, and how to prevent it, check the U.S. Surgeon General's Report.
