Confused about Fiber?

              The Craze, at first, delivered a simple message: eat oat bran an stop worrying about cholesterol. Bombarded with advertising and worried about our health, we decided that more is better. Sales of oat-bran cereals soared, and supermarket shelves began to sag under the weight of new oat-bran products pretzels, pasta ,pie shells, potato chips, waffles and licorice. There's even an oat-bran beer.

             Then came a Harvard University study showing that oat bran may have no direct effort on cholesterol. Doer this mean oat fiber is useless? And what about wheat bran, which is touted for its ability to fight cancer? Will we soon learn that it, too, is ineffective?

            First and foremost, fiber is good for us. Moderate amounts guard against constipation and diarrhea, and probably discourage overeating. People who consume adequate fiber are less likely to contract heart disease, colon cancer and many intestinal disorders. But the benefits do not follow magically from switching breakfast cereals. Fiber must be incorporated sensibly into every meal of the day.

            The term "dietary fiber" refers to the parts of plants that pass through the human stomach and small intestine undigested - ranging from the brittle husks of whole wheat to the stringy pods of green beans to the gummy flesh of barley grains. There are two principal types: soluble and insoluble.

           When soluble fiber reaches the colon, bacteria break it down into fatty acids that can be absorbed. Two common types of soluble fiber are pectins (found in apples, or anges, and other fruits) and gums (found in foods such as oat bran and barley).

           Insoluble fiber is not broken down by bacteria in the colon. All fibrous foods contain some insoluble fiber, but the most concentrated superbly is found in corn and wheat bran. Whole grains and lentils are also rich sources.

           A balance of soluble and insoluble fiber gives digesting food a soft and bulky consistency, helping it move at a steady pace neither too fast nor too slow through the digestive tract. For centuries doctors have prescribed dietary fiber for patients suffering from both constipation and diarrhea.

          In the 1970s, however, Denis Burkitt, an English physician who ministered to rural Africans for 20 years, reported that he had rarer seen cases of heart disease, colon cancer, diverticulitis, gallstones, ulcers, hemorrhoids or irritable-bowel syndrome among his African patients. Burkitt attributed this to the ample supplies of fiber they ate each day.

          When Burkitt's claims that fiber seemed to protect against certain diseases sparked international interest, scientists began to investigate. Most of their research has focused on the two most deadly diseases: heart disease and colon cancer.

          Several studies have reported that a daily intake of oat products, which are high in soluble fiber, can lower blood cholesterol as much as 15 percent. Although the Harvard study shows no suck benefit, its results need confirmation, in put because the research subjects already bad normal cholesterol levels.

           Some scientists think soluble fiber can sweep bile acids from the small intestine, forcing the liver to use up cholesterol to manufacture more bile acids. It also appears that when intestinal bacteria ferment soluble fiber, they produce substances that travel to the liver and may block cholesterol production.

          Elevated cholesterol increases a person's chances of developing heart disease. But no research suggests that fiber directly prevents heart disease.

          Scientists trace a similarly indirect line from insoluble fiber to coon cancer. Moderate amounts of wheat bran may slow the proliferation of cells in the colon lining, which would slow the development of precancerous colon polyps. The fiber may do this by blocking the action of acids in the colon that help cancer-causing chemicals do their ditty work.

         Fiber may also battle hunger. Fibrous foods hold water and thus create more bulk, so they fill up the stomach and make you fed satisfied. What's more, a stomach full of sticky, soluble fiber such as oatmeal empties more slowly, prolonging the time until you feel hungry again.

The crucial factor is we do benefit from fiber. Here are some suggestions:

1. Think of fiber as food, not medicine. Nutritionists advise against using powdered supplements or pills, because these contain very few, if any, nutrients. Fiber's benefit come from eating a variety of plant foods.

2. Eat an assortment of fibrous foods - not just bran. Variety ensures that you get enough soluble and insoluble fiber. It also allows you to take advantage of all the different nutrients fibrous foods contain. The idea is to eat fruits, vegetables, legumes and whole grains instead of your usual high-fat foods. The U.S National Research Council recommends five or more daily servings of fruits and vegetables, and at least six of whole grains and legumes. A serving consists of one slice of bread; a small roll or muffin; a half-cup of vegetables, chopped fruits, legumes or cooked cereal; a single piece of whole fruit. If you don't want to count serving, just see that foods from plants takes up three-fourths of your plate.

3. Remember that some foods are more fibrous than others. A carrot contain about twice as much fiber as a stalk of celery. An apple, eaten with the skin, has about five times the fiber of a watermelon slice. Pinto beans pack nearly double the fiber of chickpeas. Whole-grain crackers have four to six times as much fiber as saltines. Pay attention to the way food is prepared. Processing can reduce fiber content. A cup of apple juice, for example, has only about one twentieth the fiber of a single whole apple because, in preparing the juice, the skin and other textural components of the apple are left behind. In the case of breads, crackers or cereals, simply read the labels, but remember that names can be misleading. Many brown-color breads called wheat or multi-grain are made with highly refined flour, meaning most of the fiber has been milled out.

4. Add fiber to your diet gradually. Bacteria in the colon ferment fiber, and you have to give them a chance to get ready. Nutritionists recommend taking up to six weeks to bring your intake of fiber to a healthy level. Begin, for example, by eating a banana and a small bowl of bran cereal at breakfast instead of sweet pastry. In a week or so, switch to whole-grain bread. At dinner, gradually increase the brown rice, vegetables and fruits, as you pare your servings of meat and desert. If you experience gas of cramps, cut back for a few days And try exercise, such as walking 20 to 30 minutes a days. Also remember, the more fiber you eat, the more water and other fluids you need to drink. Like any sponge, fiber is pliable only when wet.

5. Don't overdo. Because fiber is so bulky, it takes some effort to overeat. But there are some people who, assuming more is better, stuff themselves with bran muffins or cereal. Discomfort is not the only danger. An oversupply of fiber can keep the body from absorbing adequate amounts of minerals critical for growth. With a varied diet, most people won't have to worry, but if may be a problem for the elderly and small children, who don't eat as much.

           Children under age two need generous amounts of calories to grow, and they need fat to help build a healthy brain and nervous system. “Too much fiber can cause little tummies to get full before they can eat enough calories for normal growth and development,” says Felicia Busch, a registered dietitian, and spokesperson for the American Dietetic Association. “As children grow, they mimic the diets of their parents. If you eat a varied diet that includes lost of fiber-rich foods, your children will too.”

           These suggestions add up to a timeless piece of advice: eat a variety of foods in moderation. Indeed, that nugget of dietary wisdom, known at least since the time of Hippocrates, is well supported by the latest scientific research on fiber.

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