You want to make sure your child gets the right vitamins and minerals. While it may seem as simple as choosing a multivitamin off the shelf, that’s not always true.

The fact that it’s easy to find over-the-counter vitamins doesn’t mean you should use them, says children’s dietitian Marilyn Tanner, R.D., L.D. It’s best for kids to get all the nutrients they need from food. The American Dietetic Association (ADA) says parents should go by the Food Guide Pyramid (www.nal.usda.gov/fnic/Fpyr/pyramid.html).

“There’s no difference between vitamins made in the lab and those in foods — it’s all of the other bonuses in the food, such as phyto-chemicals that we may not yet know about,” says Ms. Tanner, an ADA spokesperson.

But there are some children who may need a supplement. Ask your doctor if your child is one of them. Children who may need supplements include vegetarians, vegans, those with ailments like cystic fibrosis, and those with poor appetites or fickle eating habits.

Teen girls may also need supplements. A lot of them try to cut back on calories, says Ms. Tanner, robbing themselves of vitamins and minerals. Girls who menstruate lose iron each cycle, so a multivitamin with iron may help head off anemia.

If your doctor suggests a vitamin supplement, treat it as medication that can be toxic in large doses. Keep supplements in a safe place where your child can’t get to them. And teach your child that vitamins and candy are not the same thing.