A high-fiber diet is increasingly popular as people have become more active in maintaining their health. It was once thought that food fibers have no food value as such. Today however, food fibers are considered valuable constituents in the diet. The most commonly recognized benefit of a high-fiber diet is that it keeps one “regular”; that is, it helps prevent constipation.
Often also referred to as roughage, fiber is a nonnutritious material found in food which is not digested by the enzymes in the digestive tract. This indigestible material in food stimulates the intestine to peristalsis – the successive waves of involuntary contraction passing along the intestine’s walls and forcing the contents onward. A high-fiber diet is also helpful in preventing diarrhea, hemorrhoids, diverticulitis (a painful inflammation of the diverticula – small pouches along the colon wall), and irritable bowel syndrome.
There are two kinds of food fiber: insoluble and soluble. Insoluble, or nonabsorbent, food fibers can be found in cereals, seeds, legumes, whole grains, and in many kinds of vegetables and fruits. These food fibers increase the bulk and liquid content of the feces, making them softer and thus easier to pass through the intestines. As the passage of feces is made easier, less strain is placed on the intestines, effectively decreasing the risk of developing hemorrhoids.
Insoluble food fibers reduce the absorption of cancer-causing agents and lessen the amount of time these agents remain in the digestive system; hence, insoluble food fibers may likewise diminish the risk of colon cancer.
Soluble, or absorbent, food fibers – which can be found in legumes, lentils, beans, barley, oats, many types of vegetables, apples, pears, and other fruits – absorb water as they pass through the stomach and intestine. These food fibers produce a feeling of fullness, thus controlling one’s appetite. Also, soluble food fibers slow the digestive tract’s absorption of food; levels of blood cholesterol may be lowered in this way, reducing the risk of heart disease.
When switching to a high-fiber diet, it is necessary to increase the consumption of food fibers gradually to minimize bloating and flatulence. It is also important to drink lots of liquids to avoid constipation. Some fibrous foods are difficult to digest and, therefore, should be excluded from the diet and replaced with other fiber-rich foods.
Also note that fiber supplements can help, but, unlike a high-fiber diet, they contain no nutrients and can be expensive. These supplements should be taken only if a high-fiber diet causes stomach distress. They should not be taken, on the other hand, if you have a serious intestinal disorder.