A refined grain means that the bran and germ have been removed leaving only the starchy endosperm. Refining grains results in a finer-textured product with a longer shelf life. But it also eliminates many important nutrients and fiber.

September celebrates National Whole Grains Month. You’ve likely heard you should eat whole grains, but you may not know what exactly a whole grain is, why they are good for us or how much to eat each day.

“Whole grain” simply means that all of the original parts of the grain — the bran, germ and endosperm — are still present and in the same proportion as when growing in the field. The bran is the multi-layered outer skin of an edible kernel. Bran contains lots of fiber, B vitamins and antioxidants.

The germ is essentially a grain’s embryo and the part that would sprout. The germ contains B vitamins, protein, minerals and fat. The endosperm is the germ’s food supply, providing essential energy to the young plant. The endosperm is the largest part of the kernel and contains starchy carbohydrates and protein but little vitamins or minerals.

A refined grain means that the bran and germ have been removed leaving only the starchy endosperm. Refining grains results in a finer-textured product with a longer shelf life. But it also eliminates many important nutrients and fiber.

Since the early 1940s, refined grains have been fortified by adding back some, but not all, of the vitamins that were removed. This fortification is extremely important in preventing vitamin deficiency diseases such as pellagra and beriberi, as well as decreasing neural tube birth defects.

Whole grains not only provide essential vitamins and minerals not found in other foods but also valuable antioxidants different from those found in fruits and vegetables. Whole grains are an excellent source of fiber, which is found only in plant foods. The soluble fiber in whole grains helps bind with fatty acids in the body to help lower cholesterol. Insoluble fiber, or roughage, keeps the gut pH healthy, helps keep bowels regular and decreases food transit time in the gut, which helps prevent diverticulitis, a painful colon condition. Regularly eating enough fiber also can help reduce the risk of various diseases, including cardiovascular disease, diabetes and cancers. Adults should have between 25 and 35 grams of fiber each day.

Whole grain doesn’t mean just whole wheat. All whole wheat is a whole grain, but not all whole grains are whole wheat. Barley, brown rice, buckwheat, bulgur, corn, millet, oats, quinoa and rye are also types of whole grains. Finding whole grain foods can be a little tricky because many labels are deceptive. Multi-grain, 100-percent wheat, bran, cracked wheat or stone ground are all words that imply a whole grain but likely are not. Color, likewise, is not a reliable indicator of a whole grain. Instead look for the following.

Check the ingredient label for the word “whole.”

Look for a stamp from the Whole Grains Council. This will ensure that there is at least half of a serving of whole grain inside.

Check fiber content. If there is little or no fiber, it can’t be a whole grain. One slice of whole grain bread should have at least five grams of fiber.

Whole grains can be white. Albino wheat yields a lighter color, milder tasting whole wheat product.

Try to make at least half of your grains whole grain. Research from the Whole Grains Council shows that three servings of whole grains daily can reduce your risk for heart disease by 25 to 36 percent, stroke by 37 percent, Type 2 diabetes by 21 to 30 percent, digestive system cancer by 21 to 43 percent and hormone-related cancer by 10 to 40 percent. One serving of a whole grain is about an ounce, or one slice of bread, one cup of cereal or half of a cup of rice or pasta.

Check out these easy ways to incorporate whole grains into your diet.

•Switch to whole grain breads and pastas.

•Substitute brown or wild rice for white rice.

•Choose whole grain cereals such as oatmeal, bran flakes or shredded wheat.

•Add some barley to soups and stews.

•Substitute half the flour in your baking with whole wheat flour. It may be whole wheat pastry flour or white whole wheat flour for a finer texture.

•Use rolled oats or crushed whole grain cereal for breading or fillers in recipes.

•Snack on popcorn, also a whole grain. Just be sure to choose popcorn with minimal salt and butter.