The Importance of Dietary Fiber
By Laura Lee - January 29, 2022

Dietary fiber is the portion of plant foods that cannot be broken down by digestive enzymes. This includes non-starch polysaccharides (cellulose, hemicelluloses, pectin, gums), oligosaccharides, or resistant starches. Dietary fiber is classified according to its solubility in water. Insoluble fiber does not dissolve in water and passes undigested through the digestive system. Soluble fiber dissolves in water to form a gelatin-like substance that can reduce blood cholesterol levels, regulate intestinal functions and prevent constipation. Although there are many forms of dietary fiber, humans require three main types: cellulose, hemicellulose, and lignin. Dietary fibers are often referred to as roughage or bulk, which is a non-scientific term that describes the indigestible portion of food derived from plants. In general, fibers can be soluble (e.g., pectin, inulins, mucilages) or insoluble (e.g., cellulose).

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