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 do not 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 and can lead to serious injuries. This is why it is 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 protects 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 (mg)
• Ages 4 to 8 years: 1,000 mg
• Ages 9 to 18 years: 1,300 mg
• Ages 19 to 50 years: 1,000 mg

How can you get enough calcium?

Calcium is in foods such as milk, cheese, and yogurt. Vegetables like broccoli, kale, and Chinese cabbage have calcium. You can get calcium if you eat the soft edible bones in canned sardines and canned salmon. Foods with added (fortified) calcium include some juices, soy or other plant-based beverages, and tofu. The food label will show how much calcium 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 1,100 mg. So if one serving of a food has a daily value of 20% of calcium, that food has 220 mg of calcium in one serving.

Some people who do not 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 helps your body absorb the calcium better. Try not to take more than 500 mg of calcium supplement at a time.