About 80% of people do not get enough vitamin (维生素) D every day. But this vitamin is very important for your health. 

Vitamin D is really important for our bones (骨骼). When we are young, vitamin D builds up our bones and makes them strong. When we are older, we still need vitamin D to keep our bones strong. Our bodies keep the vitamin D in our bones and teeth. Then we lose vitamin D as we work and exercise during the day. But our bodies can't make vitamin D. So we have to get it from outside of our bodies.

Where can a person get this very important vitamin? Vitamin D is in foods like fish and eggs. Sometimes, vitamin D is added to bread, milk, and orange juice. Food is not the only way our bodies can get vitamin D. The sun also gives us vitamin D. If we want to be healthy, we should spend some time in the sun each day. Too much sun is not good for you, but about 15 minutes a day is usually enough. And we should be sure to eat foods that are rich in vitamin D, too.