The implications of dietary fiber

Dietary fiber is the structural part of plants found in vegetables, fruits, grains, and legumes. The food industry has found many ways to improve and enhance our food supply through the use of soluble and insoluble fibers and prebiotics. Gums, pectins, some hemicelluloses, and mucilages are classified as soluble fibers. Insoluble fibers include cellulose, many hemicelluloses, and lignins. Undigested fiber used as food by probiotic bacteria are referred to as prebiotics. Prebiotics are complex carbohydrates such as inulin or short-chain sugars called oligosaccharides. Most health benefits derived from dietary fibers occur as a result of mechanisms in the digestive tract. Not all mechanisms are fully understood but dietary fibers are known to slow the absorption of nutrients and other constituents by trapping molecules and preventing their contact with absorptive surfaces, delay cholesterol absorption, bind bile for excretion, stimulate bacterial fermentation in the colon, and increase stool weight by holding water within the feces. Research supports that these underlying actions attribute to the health benefits of dietary fibers in chronic diseases such as heart disease, cancer, diabetes, and obesity.