Learning About Calcium

What is calcium?

Calcium keeps your bones and muscles—including your heart—healthy and strong.

Your body needs vitamin D to absorb calcium. People who don't get enough calcium and vitamin D throughout life have an increased chance of having thin and brittle bones (osteoporosis) in their later years. Thin and brittle bones break easily. They can lead to serious injuries. This is why it's important for you to get enough calcium and vitamin D as a child and as an adult. It helps keep your bones strong as you get older. And it protects you against possible breaks.

Your body also uses vitamin D to help your muscles absorb calcium and work well. If your muscles don't get enough calcium, then they can cramp, hurt, or feel weak. You may have long-term (chronic) muscle aches and pains.

How much calcium do you need?

How much calcium you need each day changes as you age. Here are the recommended dietary allowances (RDAs) for calcium:

• Ages 1 to 3 years: 700 milligrams
• Ages 4 to 8 years: 1,000 milligrams
• Ages 9 to 18 years: 1,300 milligrams
• Ages 19 to 50 years: 1,000 milligrams
• Males 51 to 70 years: 1,000 milligrams
• Females 51 to 70 years: 1,200 milligrams
• Ages 71 and older: 1,200 milligrams

If you are pregnant or breastfeeding, you need the same amount of calcium as other people your age.

How can you get enough calcium?

Calcium is in foods such as milk, cheese, and yogurt. Vegetables like broccoli, kale, and Chinese cabbage also have it. You can get calcium if you eat the soft edible bones in canned sardines and canned salmon. Foods with added (fortified) calcium include some cereals, juices, soy drinks, and tofu. The food label will show how much of it was added.

You can figure out how much calcium is in a food by looking at the percent daily value section on the nutrition facts label. The food label assumes the daily value of calcium is 1,300 mg. So if one serving of a food has a daily value of 20% of calcium, that food has 260 mg of calcium in one serving.

Some people who don't get enough calcium may need supplements. Two common calcium supplements are calcium citrate and calcium carbonate. Calcium carbonate is best absorbed when it is taken with food. Calcium citrate can be absorbed well with or without food. Spreading calcium out over the course of the day can reduce stomach upset. And your body absorbs it better when it is spread over the day. Try not to take more than 500 mg of calcium supplement at a time.