American Academy of Pediatrics


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What Calcium Is and Why You Need It

Calcium is a mineral that your body needs. Its main job is to build strong bones and teeth. Your bones store calcium for the rest of your body, like a bank keeps money for when you need it.

You need the most calcium when you are between 9 and 18 years old. By the time you are 21 years old, your bones are as strong as they will ever be. From then on, your body mainly takes calcium out of your bones.

If you don't get enough calcium, your body will take the calcium it needs from your bones. They will get weak. They can break when you run or dance.

When you get older, you could have a disease called osteoporosis (ah-stee-yoh-puh-ROH-sis). It makes bones so fragile, they can break from just bending over. By then, it is usually too late to rebuild your bones.

How to Get Calcium

The best way to get calcium is by eating foods with lots of calcium. Here are some of the best ones:

  • Low-fat milk, yogurt, and other milk products (These have the most calcium.)

  • Flavored milks, like chocolate or strawberry (These can have more calories than plain milk.)

  • Kale, collard greens, and other dark green, leafy vegetables (but not spinach)

  • Chickpeas, lentils, split peas

  • Canned salmon and sardines (and other fish with bones)

  • Cereals and juices with added calcium(No more than 1 cup of juice a day, or you’ll get too much sugar.)

  • Tofu, soy milk with calcium added (Check the label.)

Ask the doctor if you think you need to take extra calcium or if you have trouble digesting milk.

How Much Calcium Do You Need?

This depends on your age. Here's what is recommended:

Daily Calcium Needs

Age You Need This Much Calcium (mg per day)

4–8 years

800 mg

9–18 years

1,300 mg

19–50 years

1,000 mg

Calcium is measured in milligrams.

The short way to write milligrams is mg.

Source: National Academy of Sciences

Tips for Getting More Calcium

  • Choose milk or smoothies instead of soda pop.

  • Add calcium to salads with low-fat cheese, tofu, or beans.

  • Choose low-fat yogurt as a snack. Add it to pancakes, waffles, shakes, salad dressings, dips, and sauces.

  • Look for foods with added calcium.

How to Read Food Labels

Food labels list the amount of calcium in a serving as “% Daily Value,” not as milligrams (mg). 100% of the Daily Value = 1,000 mg of calcium per day for an adult.

But, if you’re between 9 and 18 years old, you need 1,300 mg a day (not 1,000 mg).

Here's an easy way to find out how many milligrams of calcium are in a serving. Then you can add them up.

Put a “0” at the end of the number listed for the daily value to get the number of milligrams.

For example, a serving of orange juice with added calcium might list the amount of calcium as 30% of the daily value.

30% Daily Value = 300 mg calcium

Usually, foods with at least 20% daily value (200 mg) are high in calcium. Foods with less than 5% of the daily value are low in calcium.

Other Tips for Strong Bones

Calcium doesn't work alone. You need 3 more things:

  • A healthy diet—Eat lots of fruits, vegetables, and whole grain foods.

  • Exercise—Get lots of weight-bearing exercise. This is any exercise you do on your feet, like walking, running, dancing, tennis, or soccer. You can also lift weights to help your bones.

  • Vitamin D—This can come from:

    • Sunlight. (Your body makes vitamin D when the sun shines on your skin.)

    • Milk, other dairy products, drinks, and foods, like cereals, with added vitamin D. (Check the label.)

    • Multivitamins (mull-tee-VYE-tuh-minz).

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