Calcium

Calcium is a soft, silver-white metal found all around the world. It is one of the most common things in Earth's crust. Calcium is very important for living things. Your bones and teeth are made mostly of calcium. It helps them grow strong and hard.

Calcium in Your Body

Your body needs calcium every day to build strong bones. Kids need extra calcium because they are still growing. You can get calcium from milk, cheese, and yogurt. Green veggies like broccoli and spinach also have calcium. Without enough calcium, bones can become weak and break easily.

Calcium in Nature

Calcium is found in many rocks like limestone, marble, and chalk. Seashells, eggshells, and coral are also made of calcium. When caves form, dripping water leaves calcium behind to make stalactites and stalagmites. Even the white cliffs in some places are made of calcium from tiny sea creatures. Calcium helps shape much of our world.

Fun Facts

• About 99 percent of the calcium in your body is in your bones and teeth.
• Chalk used on blackboards is made from calcium.
• Cows make milk with lots of calcium to help baby cows grow.

Did You Know?

Your bones keep getting stronger until about age 30, so eating calcium when you are young is very important.