Get to Know Grains: The Foundation of Good Nutrition
Susan M. Kleiner, PhD, RD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 25 - NO. 6 - JUNE 97
Thousands of years ago, the Israelites took unleavened bread with them on their flight from Egypt into the desert. Today, bread and cereal products form the base of the US Department of Agriculture (USDA) food guide pyramid. For ages, grains have been the foundation for good nutrition.
The food guide pyramid shows that you need generous amounts of these foods each day to maintain health and prevent disease. But according to most surveys, at about 21% of total calories—a little over a third of the ideal percentage—Americans consume much less grain food than the rest of the world. Perhaps this article will help you include more grains in your diet.
What Is a Grain?
Grains are the seeds or fruits of cereal grasses. The unprocessed kernels are made up of several layers surrounding a core. Within the core is the "germ," which contains unsaturated fat, protein, iron, niacin, thiamin, and riboflavin. The germ is surrounded by the endosperm, a layer of starch embedded in a protein matrix. A layer of bran, made up mainly of indigestible fiber but also containing iron, thiamin, niacin, riboflavin, and some protein, surrounds these inner parts. Finally, an outermost inedible layer, the hull, protects the entire seed.
The word "cereal" is derived from the name of the Roman grain or harvest goddess, Ceres. Naturally occurring grains include amaranth, barley, buckwheat, millet, wheat, rice, corn, rye, and oats. Triticale is a man-made hybrid of wheat and rye. Cereal products made from grain include breakfast foods, rice, flours, and pastas.
Although primitive humans may have gnawed on the whole berries, today we grind or mill grains to improve their cooking time, satisfy taste preferences, and improve shelf life.
The process of milling involves a subdivision of the grain. Wheat can be milled into coarse cracked wheat, fine granular wheat, or whole wheat or white flour. Hominy, the endosperm of the corn kernel, can be cracked for grits or ground into cornmeal. Rice bran is removed to yield white or "polished" rice, and barley bran is removed to make pearl barley.
When the bran and germ are removed in processing as in refined white flour or white rice, the nutrients they contain are lost. Enriched cereals have had iron, thiamin, niacin, and riboflavin—the main nutrients lost during processing—added back in after the milling process. Sometimes calcium and vitamin D are also added.
High in carbohydrates and low in fat, grains are the ideal food to fuel your muscles. When you're getting 55% to 60% of your energy from carbohydrates, the glycogen in your muscles stays at peak supply— and you'll stay well-fueled for high-energy sports.
Recently, grains have gained popularity with the realization of their preventive health benefits. The water-insoluble fibers found in wheat bran help prevent constipation and diverticular disease and have been associated with a decreased risk for bowel cancer. The water-soluble fibers in oat bran and barley have been shown to lower blood cholesterol and blood glucose levels, which helps in the prevention and management of cardiovascular disease and diabetes. Since refined cereal products have had the bran removed, you need to eat whole- grain products if you want to reap the health benefits of bran.
Grains can also provide protein; they provide almost half (47%) of the dietary protein needs of the world population (1). The percentage is much lower in the United States, where 90% of the edible plant protein is fed to animals. Although no individual grain provides the full complement of essential amino acids (protein building-blocks), the combination of grain foods with a reasonable variety of other foods such as beans can be a complete protein source. This is true even for people who don't eat meat or dairy foods.
Going With the Grain
Grains have been thought of mainly as side dishes. But according to the USDA, a healthy diet includes 6 to 11 servings of grain foods every day, as compared with a maximum of 5 servings from any of the other food groups. But serving sizes specified in the guidelines are small, so it's not difficult to get the recommended amount each day. One serving of a grain product is defined as 1 slice of bread, 1 ounce of ready-to-eat cereal, or H cup of cooked cereal, rice, or pasta. If you had 2 slices of French toast at breakfast, a sandwich and 2 granola bars at lunch, 4 graham crackers as an afternoon snack, and a pasta dish with a large square of corn bread at dinner, you've eaten about 11 grain servings.
Cooking instructions are usually printed on prepackaged grains. But if you buy them in bulk, you're on your own to figure out cooking times and proportions of grain and water. See table 1 (not shown) for a guide that should help you as you learn to add more grains to your diet.
We're well accustomed to eating wheat, corn, and oats, and eating more of the same might not sound very interesting. You can give your menus variety and an international flair by incorporating less-familiar grains in place of the standard pastas or rice. For instance, tabbouleh, a Middle Eastern dish, is a delicious cold salad made from bulgur. The Russians traditionally use kasha (roasted buckwheat groats) to make both warm and cold dishes and stuffings. Barley makes a hearty soup, and pearled semolina is the usual variety of wheat for couscous, a Moroccan stew.
You can also increase your fiber and nutrition intake and boost your number of grain servings when preparing foods or baking. Oat bran can be added to just about any hot or cold cereal, or to cake or muffin batter. Substitute whole-wheat flour for one third to half of the all-purpose flour in your favorite recipes. And experiment with triticale, barley, rye, and oat flours when making breads and muffins. To put some variety into your flapjacks, try the blueberry buckwheat pancake recipe on page 108 (not shown).
Remember: You, your physician, and your nutritionist need to work together to discuss nutrition concerns. The above information is not intended as a substitute for appropriate medical treatment.
Dr Kleiner is a private nutrition consultant to athletes in the Seattle area. She is a member of the American College of Sports Medicine; a member of the American Dietetic Association and its practice group, Sports and Cardiovascular Nutritionists (SCAN); and a fellow of the American College of Nutrition.
Copyright (C) 1997. The McGraw-Hill Companies. All Rights Reserved