Vitamins

Vitamins are tiny chemicals that your body needs to stay healthy. You only need a small amount of each one, but you cannot live without them. Your body cannot make most vitamins on its own. You have to get them from the food you eat.

There are 13 vitamins that humans need. Each one has a letter name, like vitamin A or vitamin C. Some have number names too, like vitamin B12. Each vitamin does a different job inside your body. Vitamin A helps your eyes see in dim light. Vitamin C helps cuts heal and keeps your gums healthy. Vitamin D helps your bones grow strong. The B vitamins help your body turn food into energy. Vitamin K helps your blood form scabs when you get a cut.

Vitamins come from many kinds of food. Oranges and strawberries have lots of vitamin C. Carrots and sweet potatoes have vitamin A. Eggs, fish, and milk have vitamin D. Leafy green vegetables like spinach are packed with vitamin K and several B vitamins. This is one big reason grown-ups tell kids to eat fruits and vegetables. A meal of just one food, like only bread, is missing many of the vitamins you need.

Vitamin D is a strange one. Your skin can actually make it when sunlight hits you. Spending a little time outside helps your body build its own supply. People who live in cold, cloudy places sometimes do not get enough sun in winter, so doctors may tell them to take a vitamin D pill.

Without enough vitamins, people get sick in specific ways. A disease called scurvy, caused by a lack of vitamin C, made sailors lose their teeth on long ocean trips hundreds of years ago. A lack of vitamin D can make children's bones soft and bent, a disease called rickets. These illnesses are rare today in places where people eat a wide mix of foods.

You can also get too much of some vitamins. Vitamin pills, called supplements, can be helpful when a person is missing a vitamin. But more is not always better. Some vitamins build up in the body and can cause harm if you take huge amounts. Doctors say most kids who eat a normal mix of foods do not need extra vitamin pills at all.

The word "vitamin" was invented just over 100 years ago. Before that, no one knew these tiny chemicals existed. Yet humans had been eating them, and needing them, the whole time.