The Role of Calcium Calcium is needed for our heart, muscles, and nerves to function properly and for blood to clot. Inadequate calcium significantly contributes to the development of osteoporosis. Many published studies show that low calcium intake throughout life is associated with low bone mass and high fracture rates. National nutrition surveys have shown that most people are not getting the calcium they need to grow and maintain healthy bones. To find out how much calcium you need, see the Recommended Calcium Intakes (in milligrams) chart below. Recommended Calcium Intakes Life-stage group mg/day Source: Food and Nutrition Board, Institute of Medicine, National Academy of Sciences, 2010. Infants 0 to 6 months 200 Infants 6 to 12 months 260 1 to 3 years old 700 4 to 8 years old 1,000 9 to 13 years old 1,300 14 to 18 years old 1,300 19 to 30 years old 1,000 31 to 50 years old 1,000 51- to 70-year-old males 1,000 51- to 70-year-old females 1,200 70 years old 1,200 14 to 18 years old, pregnant/lactating 1,300 19 to 50 years old, pregnant/lactating 1,000 To learn how easily you can include more calcium in your diet without adding much fat, see the Selected Calcium-Rich Foods list below. Selected Calcium-Rich Foods Food Calcium (mg) Source: The 2004 Surgeon General’s Report on Bone Health and Osteoporosis: What It Means to You. U.S. Department of Health and Human Services, Office of the Surgeon General, 2004, pages 12–13. Fortified oatmeal, 1 packet 350 Sardines, canned in oil, with edible bones, 3 oz. 324 Cheddar cheese, 1½ oz. shredded 306 Milk, nonfat, 1 cup 302 Milkshake, 1 cup 300 Yogurt, plain, low-fat, 1 cup 300 Soybeans, cooked, 1 cup 261 Tofu, firm, with calcium, ½ cup 204 Orange juice, fortified with calcium, 6 oz. 200–260 (varies) Salmon, canned, with edible bones, 3 oz. 181 Pudding, instant (chocolate, banana, etc.) made with 2% milk, ½ cup 153 Baked beans, 1 cup 142 Cottage cheese, 1% milk fat, 1 cup 138 Spaghetti, lasagna, 1 cup 125 Frozen yogurt, vanilla, soft-serve, ½ cup 103 Ready-to-eat cereal, fortified with calcium, 1 cup 100–1,000 (varies) Cheese pizza, 1 slice 100 Fortified waffles, 2 100 Turnip greens, boiled, ½ cup 99 Broccoli, raw, 1 cup 90 Ice cream, vanilla, ½ cup 85 Soy or rice milk, fortified with calcium, 1 cup 80–500 (varies) Calcium Culprits Although a balanced diet aids calcium absorption, high levels of protein and sodium (salt) in the diet are thought to increase calcium excretion through the kidneys. Excessive amounts of these substances should be avoided, especially in those with low calcium intake. Lactose intolerance also can lead to inadequate calcium intake. Those who are lactose intolerant have insufficient amounts of the enzyme lactase, which is needed to break down the lactose found in dairy products. To include dairy products in the diet, dairy foods can be taken in small quantities or treated with lactase drops, or lactase can be taken as a pill. Some milk products on the market already have been treated with lactase. Calcium Supplements If you have trouble getting enough calcium in your diet, you may need to take a calcium supplement. The amount of calcium you will need from a supplement depends on how much calcium you obtain from food sources. There are several different calcium compounds from which to choose, such as calcium carbonate and calcium citrate, among others. Except in people with gastrointestinal disease, all major forms of calcium supplements are absorbed equally well when taken with food. Calcium supplements are better absorbed when taken in small doses (500 mg or less) several times throughout the day. In many individuals, calcium supplements are better absorbed when taken with food. It is important to check supplement labels to ensure that the product meets United States Pharmacopeia (USP) standards. Vitamin D The body needs vitamin D to absorb calcium. Without enough vitamin D, one can’t form enough of the hormone calcitriol (known as the “active vitamin D”). This in turn leads to insufficient calcium absorption from the diet. In this situation, the body must take calcium from its stores in the skeleton, which weakens existing bone and prevents the formation of strong, new bone. You can get vitamin D in three ways: through the skin, from the diet, and from supplements. Experts recommend a daily intake of 600 IU (International Units) of vitamin D up to age 70. Men and women over age 70 should increase their uptake to 800 IU daily, which also can be obtained from supplements or vitamin D-rich foods such as egg yolks, saltwater fish, liver, and fortified milk. The Institute of Medicine recommends no more than 4,000 IU per day for adults. However, sometimes doctors prescribe higher doses for people who are deficient in vitamin D. A Complete Osteoporosis Program Remember, a balanced diet rich in calcium and vitamin D is only one part of an osteoporosis prevention or treatment program. Like exercise, getting enough calcium is a strategy that helps strengthen bones at any age. But these strategies may not be enough to stop bone loss caused by lifestyle, medications, or menopause. Your doctor can determine the need for an osteoporosis medication in addition to diet and exercise.