Get the calcium you need—and not just from milk
By Suzanne Girard Eberle, MS, RD
Affirmations keep rolling in that consuming a calcium-rich diet makes a better body. Although it's been known for decades that calcium is key for building and maintaining strong bones and warding off osteoporosis, evidence now points to calcium as also being an important factor in improving blood pressure, in thwarting certain cancers, and perhaps even in regulating the body's ability to keep off unwanted pounds.
Dairy foods have traditionally occupied center stage during any discussion of calcium, thanks to their calcium-rich nature (and a great advertising campaign by dairy companies). However, concerns about hormone-laden milk and lactose intolerance have prompted some shoppers to seek out calcium-rich dairy alternatives. Once you know what to look for, it's easy to get your daily dose of this essential mineral from a number of sources.
Calcium is a critical component to good health. It builds a strong skeleton, helps muscles to contract and relax, enables nerves to send messages, and helps blood to clot. To maintain the support of these bodily functions, calcium (regulated by hormonal signals) constantly moves in and out of bones as needed. Ninety-nine percent of the body's calcium is stored in bones.
As adults, we require 1,000 mg of calcium a day. Pregnant women, kids, and teens need even more. Children need 1,300 mg during the prime bone-building years from ages 9 to 18. Bone mass accumulates rapidly during adolescence; we begin to make calcium "withdrawals" from this "bone bank" at around ages 30 to 35, when bones stop growing. Those 50 and older need to push their daily calcium intake up to 1,200 mg to guard against osteoporosis, a disease marked by frail bones and an increased risk of fractures as bone loss outpaces bone formation. Those with a family history of bone loss need to be especially careful about their calcium intake because a poor diet featuring inadequate vitamin D or excessive intake of soft drinks, salt, caffeine, and animal protein may increase the body's urinary excretion of calcium and thus decrease the body's calcium stores.
Is Dairy For You?
If your body tolerates lactose (milk sugar), organic dairy foods offer a safe and convenient way to meet your calcium needs. A cup of low-fat milk or yogurt or 1-1/2 ounces of cheese (about the size of a ping-pong ball) each delivers 300 mg of calcium, almost one-third of the daily 1,000 mg adult requirement.
Periodically, large population-based studies reveal both negative and positive associations between dairy product consumption and specific health issues. Researchers performing one recent study found that men who consumed more than 2.5 servings of dairy foods a day were one-third more likely to develop prostate cancer compared with those who ate one-half a serving or less (American Journal of Clinical Nutrition, 2001, vol. 74, no. 4). On the other hand, data from a new ten-year study of more than 3,000 overweight young adults, ages 18 to 30, showed that those who consumed dairy products five or more times daily were 70 percent less likely to develop insulin resistance syndrome, also known as Syndrome X (characterized by the body's inability to control blood sugar, increasing the risk of weight gain, heart disease, and diabetes), compared with those eating two or fewer dairy foods per day (Journal of the American Medical Association, 2002, vol. 287, no. 16). Results such as these warrant further research because population studies reveal statistical relationships but cannot definitively show cause and effect.
Recent findings have uncovered several additional benefits of calcium. Although the mechanisms aren't clear, it's thought that adequate calcium helps lower blood pressure, alleviates symptoms of premenstrual syndrome, and acts as an ally against colon cancer, the second-leading cause of cancer deaths in both men and women. Researchers suggest that increasing your calcium intake may also help you lose weight. According to one recent study, calcium—especially from dairy sources—appears to temporarily suppress parathyroid hormone (which helps regulate fat storage), thereby encouraging cells to burn fat rather than store it (Journal of the American College of Nutrition, 2002, vol. 21, no. 2).
Many dietitians believe the best strategy for getting enough calcium is to eat a wide variety of calcium-rich foods. Canned sardines and salmon (with bones) and calcium-fortified foods such as breakfast cereal, fruit juice, soy and rice milk, and tofu are good nondairy options. Round out your diet with dark green leafy vegetables, especially broccoli, bok choy, beet greens, collards, Chinese cabbage, turnip greens, and kale, as well as legumes (all-stars include lentils, chickpeas, black beans, great Northern beans, navy beans, and baked beans); sea vegetables; sesame seeds; almonds; soy nuts; and figs. To determine how much calcium a food contains, look for calcium on the food label and add a zero to the amount listed as the Percent Daily Value. For example, one-quarter cup of almonds provides 7 percent, or 70 mg, of calcium.
Getting the calcium you need is easier than ever these days, even if you opt to eat dairy-free. Make calcium a priority. Not just your bones will benefit; your overall health will get a boost, too.
Suzanne Girard Eberle, MS, RD, is a nutrition educator, speaker and author of Endurance Sports Nutrition (Human Kinetics Publishers, 2000).