Dietary fiber (fibre), sometimes called roughage, is the indigestible portion of plant foods that pushes food through the digestive system, absorbing water and easing defecation. It acts by changing the nature of the contents of the gastrointestinal tract, and by changing how other nutrients and chemicals are absorbed.
Dietary fiber can be soluble (able to dissolve in water) or insoluble (not able to dissolve in water). Soluble fiber, like all fi...
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Dietary fiber (fibre), sometimes called roughage, is the indigestible portion of plant foods that pushes food through the digestive system, absorbing water and easing defecation. It acts by changing the nature of the contents of the gastrointestinal tract, and by changing how other nutrients and chemicals are absorbed.
Dietary fiber can be soluble (able to dissolve in water) or insoluble (not able to dissolve in water). Soluble fiber, like all fiber, cannot be digested. But it does change as it passes through the digestive tract, being transformed (fermented) by bacteria there. Soluble fiber also absorbs water to become a gelatinous substance that passes through the body. Insoluble fiber has bulking action but is mostly unchanged by fermentation as it passes through the body.
Chemically, dietary fiber consists of non-starch polysaccharides such as cellulose and many other plant components such as dextrins, inulin, lignin, waxes, chitins, pectins, beta-glucans and oligosaccharides. The...
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