How important are whole grains in my diet?

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Q. I eat plenty of fruits and vegetables, but are whole grains also important?

A. Fruits and vegetables seem to get top billing on the healthy food list, but I put whole grains right up there. There are two types of grain: whole and refined. All grains grow as kernels, and each kernel has three layers:

• The inner germ contains many of the kernel's vitamins, minerals, and healthy oils.
• The middle layer is called the endosperm. It is primarily starch and provides the energy the kernel needs to grow.
• The outer coating, known as bran, contains most of the grain's fiber.

Common whole grains include whole-wheat flour, oatmeal, brown rice, and whole cornmeal. Refined grains are milled, which removes the bran and inner germ. White flour and white rice are examples. You want to eat more whole grains and restrict refined grains. When you eat a whole grain, you get more than just the fiber from the bran. You also get all the vitamins, minerals, good fats, protein, antioxidants, and other healthful parts of the grain's germ. Whole grains reduce your risk of heart disease and type 2 diabetes. People who follow a diet rich in whole grains also live longer compared with those who eat foods made from refined grains.

Men ages 51 and older should eat at least 6 ounces of whole grain (about 168 grams) per day. In general, 1 ounce of whole grain equals a slice of bread, 1 cup of cereal, or 1/2 cup cooked rice. It's easy enough to decide between heathier brown rice and refined white rice. But selecting whole-grain breads and cereals often requires a close reading of the product label. Don't be fooled by terms such as "wheat flour," "unbleached wheat flour," and "enriched wheat flour." They can refer to refined white flour.

The same goes for "stone-ground," "multigrain," "fortified," "stoned wheat," "cracked wheat," and "organic." None of these terms guarantees that the product is whole grain. And it's not enough that "made with whole grain" appears somewhere on the label because it may make up only a small proportion of the product.

To be sure you get real whole grains, look for the word "whole" or "whole grain" before the grain's name as the first ingredient; for example, "stone-ground whole wheat" or "100% whole wheat." Another tip is to look for the Whole Grains Council stamp on the label. (See below for other food label examples.)

— Howard LeWine, M.D.
Editor in Chief, Harvard Men's Health Watch

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