The Lowdown on Dietary Fiber

You've probably heard that you should either increase or decrease dietary fiber, so you may be wondering which advice to follow. As with most advice, much depends on the priority of any related problems you are facing: anything from basic, annoying diarrhea to changes in hormones and body shape. In cases of diarrhea, recommendations about fiber range from increasing the soluble forms of fiber to decreasing insoluble forms. Soluble forms, such as pectins and hemicelluloses'found in applesauce, potatoes, oat bran, beans and other legumes, and even the white pith of the rind of oranges'gel things up and slow things down a bit in the gut. The insoluble fibers, such as cellulose found in whole wheat and other grains, fruits, and vegetables, speed things up. But dietary fiber plays a longer-term role in your health. For instance, the problems of lipodystrophy can include high blood fats, changes in glucose tolerance and insulin sensitivity, and changes in the body's fat deposits. Connecting the dots to relate these problems to diet therapy suggests that fiber can play an important role in the treatment and maybe even the prevention of lipodystrophy-associated problems. Fibers have been touted as helping reduce blood cholesterol and have even been suggested to treat other problems, such as insulin resistance, osteoporosis, and cancers. High-fiber diets along with other sensible diet modifications and regular exercise can help you to maintain cardiovascular health and reduce an overenthusiastic insulin response to meals. Fibers work by ' slowing down digestion and absorption of nutrients from food in the stomach and intestines, ' decreasing blood sugar levels after meals, ' increasing insulin sensitivity in your body's tissues, ' increasing the number of insulin receptors to process blood sugar, ' stimulating the body's use of blood sugar, ' reducing the liver's sugar production, ' lowering blood cholesterol, ' lowering blood triglycerides (in both fasting and after-meal states), ' reducing the liver's production of cholesterol, and ' decreasing hunger between meals. General recommendations suggest an increase in fiber of up to 25 grams per day. Fiber should come from a variety of foods in your diet [see the table below]. Fibers in the diet should be increased slowly over a period of time. In some cases, especially if fiber consumption is increased too quickly, you can experience some bloating and gas production or other gastrointestinal discomforts, such as constipation or diarrhea. Fiber also has the potential to interact with medications by reducing absorption. So make an appointment and talk with your dietitian about what types of fibers fit well into your diet and which ones may help you to accomplish your therapeutic and health goals. Fiber Content of Some Typically Consumed FoodsAbout 2 grams 1 small apple 1 small banana 1 small orange 1/2 small pear 1 cup soy milk 1/4 cup miso 1 slice whole wheat, cracked wheat, or rye bread 1/2 biscuit shredded wheat 3 tablespoons Grape-Nuts cereal 1/2 cup barley 1 tablespoon All-Bran cereal 3 tablespoons dry oats (cook before eating) 1 teaspoon wheat bran 1/3 cup carrots 2-inch cob of whole kernel corn 2-inch diameter potato 1 medium tomato 1/2 cup green beans About 8 grams 1/2 cup beans or other legumes Fields-Gardner is the director of services for The Cutting Edge, an HIV nutrition company in the Chicago area. She is a member of the International AIDS Society and the American Dietetic Association's Dietetic Practice Group on HIV and AIDS. She has written a book on HIV medications and a guide to nutritional management of HIV for clinicians.