Fiber decreases blood cholesterol levels and helps prevent diverticulosis. It is also well known for preventing constipation. However, in order for fiber to do all that it is claimed to do, it is important to know that there is more than one type of fiber, and each type reacts differently in the digestive system. Consider this information.
• Fiber is the portion of a plant that is not digested by enzymes in the intestinal tract. Different types of plants also vary in the amount and type of fiber, so it is necessary to know the source of fiber.
• Fiber in plants may be identified as pectin, gum, mucilage, cellulose, hemicellulose and lignin. Pectin and gum are water-soluble fibers found inside plant cells. They slow the passage of food through the intestines but do nothing to increase bulk. Insoluble fibers such as cellulose, hemicellulose and lignin increase bulk and speed up the passage of food through the digestive tract. Wheat bran and whole grains contain the highest amounts of insoluble fiber, but vegetables and beans are also good sources.
• One benefit of a diet with the proper amount of fiber is a lower cholesterol level that is beneficial for heart health and diabetes. There is also research that links it to reduced chances of colon cancer due to proper digestive health. Finally, fiber has been linked to weight loss because of its ability to provide a “full” feeling.
• Dietary fiber is found only in plant foods, including fruits, vegetables, nuts and grains. Meat, milk and eggs do not contain fiber. The form of the food may or may not affect its fiber content. Canned and frozen fruits and vegetables contain the same amount of fiber as those that are raw. Other types of processing, though, may reduce fiber content. Dehydration doesn’t seem to reduce fiber content significantly; however, drying to a crisp state or crushing vegetables, herbs, etc., may destroy the water-holding qualities of the fiber.
• Estimates are that the average adult American consumes 14 grams of dietary fiber a day, which is considerably less than the recommended level. The current Dietary Guidelines for Americans (2010) recommends 14 grams per 1,000 calories. This averages to about 25 grams per day for women and 38 grams per day for men.
• For a label on a product to claim it is “high in fiber,” it must contain 5 grams or more of fiber per serving. Labels claiming it is a “good source” of fiber must provide 2.5 to 4.9 grams per serving.
• Although fiber is important, it is just one part of a properly balanced diet. It is possible that too much fiber may reduce the amount of calcium, iron, zinc, copper and magnesium that is absorbed from foods.
• Fiber supplements are sold in a variety of forms, from bran tablets to purified cellulose to powdered psyllium. Many laxatives sold as stool softeners are actually fiber supplements. It is important to note that the top recommendation for fiber intake is to eat a variety of fiber-rich foods. This is the best way to receive the maximum fiber benefit and obtain the necessary nutrients.
By: Kathlene Riggs - Aug. 19, 2011