By Lindsay Edwards

Nutrition experts agree that you should eat at least three servings of whole-grain foods every day. But how do you know exactly which foods are whole grain? And just what is whole grain?

Before they are milled or refined, all grains are considered whole. Whole is defined as containing all the original components of grains: an inner layer of germ, a middle layer called the endoderm, and an outer layer of bran. When grains are milled or refined, the germ and bran layers are removed, leaving the starchy endoderm. That's the layer you enjoy when you eat white rice or foods made from white flour.

So, what are some examples of whole-grain foods? Many popular foods contain whole grains, including whole-grain breakfast cereals and whole-wheat and whole-grain breads and waffles. Make sure the ingredient list on the food label says "whole" or "whole-grain."