Whole grains are grains such as wheat, rice, corn, oats, or rye which have not been refined, meaning that the whole grain is retained, rather than just the endosperm. Because the grain is left intact, these grains have more nutritional value than their refined versions, and they also tend to have a more rich, nutty flavor. Consuming a balanced amount of whole grains is an important part of a healthy diet, and if you are not sure about whether or not a food is whole grain, read the packaging with care.
Cereal grains have three main parts: the bran, the germ, and the endosperm. The bran is a coarse protective outer layer with a high concentration of fiber, niacin, thiamine, riboflavin, magnesium, iron, phosphorus, and zinc. Beneath the bran lies the endosperm, the bulk of the grain, which contains the majority of the protein and carbohydrates of the grain. At the core of the grain is the germ, a small nutrient rich nubbin which contains vitamin E, magnesium, riboflavin, phosphorus, iron, zinc, niacin, and thiamine. Small amounts of protein and fat can also be found in the germ, which is sometimes sold separately as a nutritional supplement.
Because whole grains use the entire grain, they have far more nutrients than processed grains, and are also higher in fiber. A high fiber diet can reduce the risk of cancer, diabetes, heart disease, and intestinal problems. The vital balance of nutrients found in whole grains also supports immune system health, and supplies the body with necessary vitamins and minerals. Many refined grain foods are actually supplemented to make up for the loss in nutrition caused by the removal of the bran and germ.
Many consumers have noted that whole grains tend to be darker. This is because they are not processed with chemicals like bleach, as some refined products are, and because the bran is dark in color. These products are also less shelf stable than refined products, because they contain more oil, which can go rancid if the grains are not properly cared for; the grains should be kept refrigerated until use to prevent them from going bad.
Integrating more whole grains into the human diet is relatively easy. They are available in whole, cracked, or ground form for various uses including breads, side dishes, and breakfast foods. Cooking whole grains tends to take longer because of the protective bran, and for consumers who do not have adequate cooking time, a number of companies sell packaged whole grain products like bread, tortillas, par-broiled rice, quick cooking quinoa, and other grains. Make sure to read the packaging on these items, and try to avoid products which do not list whole grains as the first ingredient.