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vegetables, and legumes (dry beans) as part of the overall recommendation to have an adequate intake of fruits and vegetables (see ch. 2).
Whole Grains
In addition to fruits and vegetables, whole grains are an important source of fiber and other nutrients. Whole grains, as well as foods made from them, consist of the entire grain seed, usually called the kernel. The kernel is made of three components—the bran, the germ, and the endosperm. If the kernel has been cracked, crushed, or flaked, then it must retain nearly the same relative proportions of bran, germ, and endosperm as the original grain to be called whole grain. In the grainrefining process, most of the bran and some of the germ is removed, resulting in the loss of dietary fiber (also known as cereal fiber), vitamins, minerals, lignans, phytoestrogens, phenolic compounds, and phytic acid. Some manufacturers add bran to grain products to increase the dietary fiber content. Refined grains are the resulting product of the grainrefining processing. Most refined grains are enriched before being further processed into foods. Enriched refined grain products that conform to standards of identity are required by law to be fortified with folic acid, as well as thiamin, riboflavin, niacin, and iron. Food manufacturers may fortify wholegrain foods where regulations permit the addition of folic acid. Currently, a number of wholegrain, readytoeat breakfast cereals are fortified with folic acid. As illustrated by the comparison of wholewheat and enriched white flours in table 6, many nutrients occur at higher or similar levels in whole grains when compared to enriched grains, but whole grains have less folate unless they have been fortified with folic acid.
Consuming at least 3 or more ounceequivalents of whole grains per day can reduce the risk of several chronic diseases and may help with weight maintenance. Thus, daily intake of at least 3 ounceequivalents of whole grains per day is recommended by substituting whole grains for refined grains. However, because three servings may be difficult for younger children to achieve, it is recommended that they increase whole grains into their diets as they grow. At all calorie levels, all age groups
should consume at least half the grains as whole grains to achieve the fiber recommendation. All grain servings can be wholegrain; however, it is advisable to include some folatefortified products, such as folatefortified wholegrain cereals, in these wholegrain choices.
Whole grains cannot be identified by the color of the food; labelreading skills are needed. Table 7 identifies names of whole grains that are available in the United States . For information about the ingredients in wholegrain and enrichedgrain products, read the ingredient list on the food label. For many wholegrain products, the words “whole” or “whole grain” will appear before the grain ingredient’s name. The whole grain should be the first ingredient listed. Wheat flour, enriched flour, and degerminated cornmeal are not whole grains. The Food and Drug Administration requires foods that bear the wholegrain health claim to (1) contain 51 percent or more wholegrain ingredients by weight per reference amount and (2) be low in fat. DI E TARY GUIDE L INE S FO R AM E R IC ANS , 2 0 0 5
Increased intakes of fruits, vegetables, whole grains, and fatfree or lowfat milk and milk products are likely to have important health benefits for most Americans.
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