Good nutrition counts just as much as exercise for bone health. "The two work synergistically," says Dee Sandquist, R.D., a spokeswoman for the American Dietetic Association (ADA).
Start with a well-rounded whole-foods diet, which should provide the vitamins, minerals, and protein needed for strong bones. Mind your alcohol, salt, and caffeinated soda intake (excessive amounts may be detrimental to skeletal health). And keep these key nutrients in mind.
Calcium helps your body build and maintain healthy bones. The Institute of Medicine (IOM) suggests that women ages 19 to 50 get 1,000 milligrams daily; women older than 51 need 1,200. Foods naturally high in calcium tend to come from dairy -- milk, yogurt, cheese (go for the low-fat versions) -- although canned versions of sardines and salmon (with bones; they're edible) make excellent sources, too.
Next best? Try almonds, broccoli, and leafy greens (Chinese cabbage, kale, collard greens, and turnip greens) -- or turn to calcium-fortified foods, including orange juice, tofu, soy milk, and cereals. If you supplement, keep in mind that your body can't efficiently absorb more than 500 milligrams at a time.
Vitamin D plays a crucial role in the development of strong bones and helps the body absorb and use calcium. The IOM recommends 200 IU daily until you reach 50 and then bumps up the amount to 400 IU; after you reach 71, it goes up even more to 600 IU. However, experts are re-evaluating that amount in light of recent research showing just how much we need this vitamin -- and how many of us aren't getting enough. Some would like to see the level raised as high as 1,000 IU daily, but don't expect a final IOM decision until next year.
For most people, the best source for D remains the sun, says Lona Sandon, R.D., a spokesperson for the ADA. Aim for 10 to 15 minutes of exposure without sunscreen during peak hours. Not many foods naturally contain D, though some fish, such as salmon and tuna, serve as good sources. You'll also find certain D-fortified products, including orange juice, milk, and cereal. If you supplement, look for D3 (cholecalciferol); your body may better metabolize this form.
Vitamin K is relatively new on the bone health scene, notes Sandquist. It appears to be a significant boost for bone metabolism and health, although its role is not clear. The IOM recommends a daily intake of 90 mcg, an amount easily obtainable through food. Indulge in a one-cup serving of leafy greens such as kale, collards, dandelion, or spinach and you'll get more than a day's worth of K. Lots of other fruits and veggies contain K, too, so load up.
Potassium helps the body maintain a normal pH level. Why should you care? When acid levels rise too high, the body pulls calcium from your bones to work its way back to normal. The IOM advises getting 4,700 milligrams a day. That might sound like a lot, but so many good-for-you foods contain potassium -- fruits, vegetables, legumes, nuts, seeds -- that it should be a breeze if you eat a whole-foods diet. Studies show that fruits and vegetables in particular may play an important role in neutralizing acid, so get the recommended five to eight servings.
Magnesium influences bone matrix and bone mineral metabolism, and studies suggest it may increase bone mineral density. Aim for 320 milligrams a day through a whole-foods diet. Particularly good sources include halibut, spinach, pumpkin seeds, and artichokes. Many legumes -- black beans, chickpeas, lentils, and soybeans, to name a few -- offer excellent amounts, too, as do a number of nuts, such as almonds, cashews, and Brazil nuts.