Most Americans don’t eat enough fiber, according to the U.S. Department of Agriculture. Fiber is a type of carbohydrate found in plants that resists digestion and absorption in the human gastrointestinal tract. Adequate dietary fiber intake has a significant effect on your gastrointestinal system and may help you move your bowels, lose weight and prevent certain types of cancers.
Fiber has a laxative effect that improves the ease and frequency of your stools. Since fiber is not digested, it continues through your gastrointestinal tract, pulling water with it. The additional load of water increases the weight of your stool and softens it, making it pass more quickly through your colon. This is important because the longer stool stays in your colon, the harder it becomes, putting you at increasing risk for constipation. Increase your water intake as you add more fiber to your diet to account for the water lost in the stool, advises the Academy of Nutrition and Dietetics.
As little as 20 grams of fiber per day may help you lose weight, states the Academy of Nutrition and Dietetics. Fibrous foods are lower in caloric density than many other foods. They also take more time to chew and help you feel full so that you consume fewer calories. Fiber slows gastric emptying and the intestinal absorption of nutrients that would otherwise raise blood sugar and lipid levels, contributing to weight gain. A 2001 article in “Nutrition Reviews” suggests that healthy individuals who consume an additional 14 grams of fiber per day eat 10 percent fewer calories and can expect to lose about 4 pounds over a four-month period.
The World Cancer Research Fund concludes that foods containing dietary fiber protect against colorectal cancer, the fourth most common cause of cancer-related deaths in the world. One proposed mechanism is that beneficial bacteria ferment fiber in your intestine, producing short-chain fatty acids which prevent cells from dividing out of control and forming cancerous tumors. The American Gastroenterology Association recommends at least 30 grams of fiber daily to protect against colorectal cancer.
Fiber Sources and Recommendations
Beans, peas, vegetables, fruits and whole grains are excellent sources of fiber. A 1/2-cup serving of beans contains up to 9.6 grams of fiber and 1/3 of a cup of bran cereal provides 9 grams, according to the U.S. Department of Agriculture. Add 1/2 cup of blackberries to your cereal for an additional 4 grams of fiber. Aim for a total dietary fiber intake of 25 grams daily for women and 38 grams per day for men, advises the USDA.