Eating the Right Amount of Fiber

Remember back in the 1980s, when oat bran bread became the toast of the town? Research suggested that eating oats and other high-fiber foods could fight heart disease and some cancers, making consumers weaned on white bread switch to dark loaves. Boring bran cereal became hip. Bakeries added oat muffins and bagels to their menus.

Food trends come and go, of course, so fiber's reputation as a health savior has faded slightly. However, fiber should never go out of fashion in your diet. There are two kinds of fiber in food:

• Insoluble fiber. As the name suggests, this is fibrous stuff in plants that doesn't dissolve as it passes through the gastrointestinal system, so you can't digest it. Instead, insoluble fiber absorbs water and helps move waste through the colon. Whole-wheat bread is a good source of insoluble fiber, as are many vegetables.

• Soluble fiber. This isn't digested, but it does get gummy in your gut. That allows it to grab fat molecules before they can be absorbed into the blood, whisking them out of the body through the intestines. Along with oat bran, dried peas and beans, barley, apples, oranges, carrots, and other fruits and vegetables are rich in soluble fiber.

Although fiber is a type of carbohydrate, your body can't digest it, so you can't burn it as energy. However, fiber has a long slate of benefits. Health authorities recommend eating 25 to 30 grams of fiber per day, yet Americans only consume about 14 or 15 grams daily, on average. Which is too bad, since:

• Fiber helps control blood sugar. Fiber in a meal slows other carbohydrates from entering the bloodstream, which prevents glucose spikes. It's as though sugar and starch molecules keep bumping into all that roughage while trying to get out of your gut. A 2004 scientific review in the Journal of the American College of Nutrition found that eating high-fiber foods consistently lowers postmeal glucose levels in people with diabetes.

Beans and lentils are packed with fiber, in addition to protein, B vitamins, and other nutrients.

• Fiber lowers cholesterol and other blood fats. The same review found solid evidence for the theory that daily doses of dietary fiber reduce cholesterol and triglycerides, another form of artery-clogging fat. That seems to be true of soluble fiber in particular; it sops up cholesterol and fat in the diet before it can enter the bloodstream.

• Fiber fills you up. So does fat -- but fat has almost twice as many calories per gram as high-fiber foods. Eating plenty of low-calorie foods that provide satiety -- that belly-pleasing sense of fullness that persuades you to set down your fork and push away from the dinner table -- can help control weight.
  

• Fiber is a freebie. Since you don't digest fiber, it has no calories. In fact, if you count carbs and consume a meal that includes more than five grams of fiber, you can subtract them from the overall gram count for the meal.
  

• Fiber has lost a tiny bit of its miracle-food image in recent years. That's because studies suggest that roughage may not reduce the risk of colon cancer, as doctors once believed. Furthermore, if you develop gastroparesis or certain other gastrointestinal complications of diabetes, your doctor may recommend cutting back on fiber-rich foods, at least temporarily.

A final caveat: While fiber supplements can offer a convenient and effective way to add bulk to your diet, try to get your fill from foods. High-fiber pills, powders, and snacks contain natural substances such as psyllium seed husks (which come from a type of plantain). But fiber-dense foods are also excellent sources of vitamins, minerals, and other salubrious stuff. What's more, it's worth noting that fiber supplements are commonly used as laxatives, so it's important to use them as -- and only when -- prescribed.

For more information on diabetes, diet, and related topics, try the following links:

• For more information about how diet affects diabetes, see our Diabetic Diet page.
• To learn how exercise relates to diet when you have diabetes, see our Diabetes and Exercise  page.
• For more information on diabetes in general, whether you want to learn about type 1 or type 2, visit the main Diabetes page.
• To learn about how to take care of yourself when you have diabetes, visit our main Diabetes Treatment page.

ABOUT THE AUTHOR:

Timothy Gower is a freelance writer and the author of several books. His work has appeared in many magazines and newspapers, including Prevention, Health, Reader's Digest, Better Homes and Gardens, Men's Health, Esquire, Fortune, The New York Times, and The Los Angeles Times.

ABOUT THE CONSULTANTS:

Dana Armstrong, R.D., C.D.E., received her degree in nutrition and dietetics from the University of California, Davis, and completed her dietetic internship at the University of Nebraska Medical Center in Omaha. In private practice for 21 years, she has developed educational programs that have benefited more than 5,000 patients with diabetes. She is the cofounder and program director of the Diabetes Care Center in Salinas, California.

Allen Bennett King, M.D., F.A.C.P., F.A.C.E., C.D.E., received his degrees and training at the University of California, Berkeley; Creighton University Medical School; the University of Colorado Medical Center; and Stanford University Medical Center. He is the author of more than 50 papers in medical science and speaks nationally on new advances in diabetes.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.