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Getting Enough Calcium

With three out of four Americans not eating enough calcium, the government is launching two new campaigns to boost its consumption by children and teen-agers -- the ages bone builds fastest.

Experts say the shortage of calcium in Americans' diets starts in childhood, when kids quickly learn to guzzle colas or sugar-filled "fruit drinks" instead of milk.

"The United States needs a national, comprehensive plan to improve the calcium nutrition of our people," Dr. Robert Heaney of Creighton University told fellow calcium specialists at a meeting last week to discuss how to do just that.

Calcium's claim to fame is building strong bones and teeth. But this versatile mineral also may play other important roles, such as lowering blood pressure or preventing colon cancer. Studies suggest that calcium may cut symptoms of premenstrual syndrome in half.

When you don't eat enough calcium, the body leaches the mineral from your bones, weakening them over time. Ten million Americans, mostly women, already have osteoporosis, where their bones are so brittle they snap.

How much calcium do you need? The Institute of Medicine set 1,000 milligrams a day as an adequate level for most adults. Teen-agers need more, 1,300 milligrams, because their bones are growing so fast.

Need varies for other ages -- 500 milligrams a day for toddlers; 800 milligrams for 4- to 8-year-olds; and 1,200 milligrams for people over age 50.

Overall, dairy products like yogurt, milk and cheddar cheese pack the most calcium. For most children, a few glasses of milk a day would meet the need. For variety, calcium-fortified orange juice has as much calcium per glass as milk.

For chocolate-loving kids, adding cocoa to skim, low-fat or regular milk can give them 300 milligrams of calcium.

Other sources may not have as much calcium as dairy, but can add up: Dark leafy vegetables, broccoli, soybeans, canned salmon.

You may be sneaking in calcium without knowing it: A slice of cheese pizza, for instance, has 220 milligrams. Two tablespoons of blackstrap molasses has about 270. A handful of almonds has 100.

Calcium supplements can help, too, but experts agree that calcium from food is best because calcium-rich foods also pack other vital nutrients.

Use supplements to "top off an otherwise good diet," Heaney advises. "They're not a substitute for good eating."

However, for millions of Americans, especially minorities, digesting lactose, or milk sugar, is a problem.

Aside from non-dairy calcium sources, lactose-free milk and tablets that aid in milk digestion are widely sold. But studies show many lactose-intolerant people can digest some milk as long as they drink it with meals, said Dr. Duane Alexander of the National Institutes of Health. And calcium-rich hard cheeses contain little lactose.

But calcium alone isn't enough. Adequate vitamin D -- from the sun, certain foods like milk or cereal, or supplements -- helps the bodabsorb calcium. High-protein diets, in contrast, can inhibit calcium absorption.

To help parents understand exactly how their children can get enough calcium, the government is offering a free booklet as part of a campaign called "Milk Matters." To get the booklet, call 1-800-370-2943.

And the U.S. Public Health Service plans to launch a special bone health campaign aimed at increasing teen-age girls' calcium consumption.

Written By Lauran Neergaard

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