Osteoporosis Tips: Build Stronger Bones
Nutrition for Strong Bones continued...
“You can pick and choose from a wide variety of sources, and can vary it day by day. On the days when you don't get as much calcium, you can take a supplement, such as calcium citrate,” says Sellmeyer.
For vitamin D, often called the key that unlocks calcium in your body, the Institute of Medicine recommends between 600 and 800 IU per day. That's harder to get, because our bodies mostly synthesize vitamin D in response to sunlight. “Between November and March, most places anywhere north of, say, Oklahoma, don't get enough UV rays to make vitamin D even if you stay out all day on a sunny winter day,” Sellmeyer says. Good sources of vitamin D include:
- Fatty fish like salmon, mackerel, and tuna
- Cod liver oil
- Fortified dairy products
- Fortified cereals
- Beef liver
- Fortified orange juice
The IOM's recommendations about vitamin D have, in fact, been somewhat controversial. Many bone experts suggest that they're on the low end of optimal. “They're a good place to start, and probably good recommendations for the general public,” says Sellmeyer. “But if you have bone issues -- a history of fractures, say, or long-term steroid use, or a lot of osteoporosis in your family -- you may need to see a doctor and get your D levels checked.”
Don't forget the third nutritional building block of strong bones: protein. Your diet should contain plenty of lean protein sources, such as lean meats and fish, beans, and cheese.
Exercise Your Right to Strong Bones
One way to see just how important exercise is to bone health is to look at what happens to bone strength when people don't exercise.
“People who have been put on bed rest, people who undergo limb immobilizations, and astronauts, who have very reduced physical activity because of the minimal actions of gravity and muscles pulling on the bone -- they all see a rapid and profound effect on the skeletal system,” says Wendy Kohrt, PhD, a professor of medicine and the director of research for geriatric medicine at the University of Colorado. “People confined to bed rest for even four months lose about 10% of their bone density in critical regions of the skeleton. It takes a very long time to get that back.”
Kohrt says the evidence shows that weight-bearing exercise can build about 1% to 3% of bone. That may not sound like a lot, but exercise may also strengthen existing bone in ways that are harder to quantify. Research from the landmark Nurses' Health Study (NHANES) shows that women who walk at least four hours per week reduce their risk of hip fracture by about 40%.
Weight-bearing exercises include walking, dancing, jogging, playing tennis. Swimming, although it's a wonderful exercise in many ways, doesn't particularly benefit bone health because it isn't a weight-bearing activity.