Eat Grains To Stave Off Diabetes

If decreased risks of heart trouble, bowel diseases, and some types of cancer weren't enough reasons to eat your wheat, researchers have now associated whole grains with better defense against type 2 diabetes (adult-onset diabetes). In a 12-year study of nearly 43,000 men, those who ate at least three servings of whole grains per day were more than 40 percent less likely to develop type 2 diabetes than those who ate few to no whole grains (American Journal of Clinical Nutrition, 2002, vol. 76, no. 3).

A whole grain consists of the entire kernel. This includes the bran, or outer shell of the seed, which contains fiber, B vitamins, and trace minerals (especially magnesium); the endosperm, or inner fat of the seed, which contains carbohydrates and protein; and the germ, or heart of the seed, which contains vitamin E, other antioxidants, and B vitamins. The processing of refined grains, such as white rice and white flour, strips away the fiber, along with much of the nutritional value.

For better health, stock your pantry with unrefined grains, such as barley, brown rice, bulgur, millet, quinoa, whole-wheat flour, and whole-wheat couscous. The mechanism by which whole grains prevent type 2 diabetes remains unknown, but Teresa T. Fung, RD, of Simmons College in Boston, lead author of the study, points to several possibilities. "Whole-grain products are high in fiber, and these slow the absorption of glucose in the digestive system. This, in turn, may create a slower and smaller rise of blood glucose than refined grains would cause," she says. "In addition, whole-grain products are higher in magnesium than refined grain products are, and some evidence exists that magnesium may—to a certain extent—help the body use glucose."

According to the current USDA Food Guide Pyramid, adults should eat six to 11 servings of grain foods daily, at least half of which should be whole grains. Americans, on average, eat only one serving of whole grains per day, which is surprising when you consider that a serving is equivalent to only one slice of bread (see sidebar).