They protect your organs, provide support and help you move, but you might take your bones for granted. Osteoporosis, a bone disease that causes weak bones that break easily, affects 4.5 million women over the age of 50 and 0.8 million men over age 50, according to the Centers for Disease Control and Prevention. Calcium, phosphorus and vitamin D are all nutrients your body needs to support healthy bones. Getting the right amount of these nutrients daily can help keep your bones healthy and strong.

About the Nutrients

Calcium and phosphorus are both minerals, while vitamin D is a fat-soluble vitamin. Ninety-nine percent of the calcium in your body is stored in your bones, the other 1 percent is used for other functions such as muscle contractions and nerve transmissions. Like calcium, most of the phosphorus in your body is found in your bones and teeth, but it is also found in every cell in your body. In addition to helping your body form bones and teeth, you also need phosphorus to help make proteins. Vitamin D helps you absorb calcium, and you also need it to promote bone growth.

Food Sources of Calcium

Adults need 1,000 to 1,200 milligrams of calcium a day. Women are more likely than men to not meet their calcium needs, according to the Office of Dietary Supplements. Good food sources of calcium include plain low-fat yogurt, with 415 milligrams of calcium per 8-ounce serving, part-skim mozzarella cheese with 333 milligrams per 1.5-ounce serving and nonfat milk, with 299 milligrams per 8-ounce serving. Other good sources of calcium include tofu, kale and turnip greens.

Food Sources of Phosphorus

Adults need 700 milligrams of phosphorus a day. Phosphorus deficiencies are rare, because the mineral is found in a variety of different foods. Good food sources include plain, nonfat yogurt, with 356 milligrams per 8-ounce serving, all bran cereal, with 339 milligrams in a 1/2-cup serving and nonfat milk, with 247 milligrams in an 8-ounce cup. Cheese, meat and beans are also good sources of phosphorus.

Food Sources of Vitamin D

Adults between the ages of 19 and 50 need 600 International Units of vitamin D a day, and adults over the age of 70 need 800 International Units. Most Americans do not meet their recommended needs for vitamin D, according to the Office of Dietary Supplements, but you are able to manufacture your own vitamin D through sun exposure. Vitamin D is found in only a few foods. Good sources include swordfish with 566 International Units in a 3-ounce portion, sockeye salmon with 447 International Units in a 3-ounce portion and vitamin D fortified nonfat milk with 115 to 124 International Units in an 8-ounce cup. Eggs and liver also contain vitamin D.