Coming in thousands of forms, fiber is a term for all parts of plant foods the body cannot digest. Found in all fruits and vegetables, as well as whole grains and legumes, fiber travels through the body without breaking down. It passes through the body and makes a quick exit. Though fiber has no calories and is not absorbed by the body, it has a variety of health benefits, such as assisting in weight loss and constipation and helping regulate various gastrointestinal disorders.
There are two types of fiber, soluble and insoluble. Soluble fiber forms a gel in the digestive tract, which slows digestion and prevents the body from absorbing too much starch and sugar. According to Jackson Siegelbaum Gastroenterology, this can lower cholesterol by 10 to 15 percent, indirectly assisting the prevention of heart disease and stroke. Soluble fiber is the type commonly found in over-the-counter laxatives. Dried beans, peas, oats, apples, citrus fruits, carrots and barley are good sources of natural soluble fiber.
Insoluble fiber absorbs water, creating bulkier stool. It also helps the bowels move quickly through the digestive tract, which is helpful to people who suffer from constipation or irregular bowel movements. Insoluble fiber is found in whole-wheat flour, wheat bran, nuts, various vegetables and peels of fruit, such as apples, blueberries and grapes.
Fiber promotes weight loss in a variety of ways. Foods rich in fiber generally take a longer period of time to chew, giving your body more time to register you are full. This can prevent you from overeating and can make you feel full for a long period of time, so you are not hungry between meals.
Both types of fiber promote digestive health, and different types of fiber can also be effective in helping irritable bowel syndrome and diverticulosis. Fiber assists the body in having regular bowel movements and increases the weight and size of stool, as well as softens it. This decreases chances of constipation and can help solidify diarrhea by absorbing water.
Fiber may also help control blood sugar levels and prevent Type 2 diabetes. According to the University of Maryland Medical Center, fiber may also help prevent various types of cancer, but further studies are needed to prove this.