Why do you need fiber in your diet?
1 Answer
Dietary fibres are an important component of our food and they act by changing the nature of the contents of the gastrointestinal tract and by changing how other nutrients and chemicals are absorbed.
Explanation:
Dietary fibres or roughage is the indigestible portion of food, derived from plants. It has two components namely the soluble fibres (soluble in water) and insoluble fibres ( do not dissolve in water).
Advantages of consuming fibres are the production of healthful compounds during the fermentation of soluble fibres. Insoluble fibres increase bulk, soften stools and shorten transit time through the intestinal tract.
Dietary fibres have three mechanisms :
Bulking
Viscosity
Fermentation
Bulking fibres absorb water and can significantly increase stool weight and regularity.
Viscous fibres thicken the content of the intestinal tract and may attenuate the absorbtion of sugar, reduce sugar response after eating and reduce lipid absorption.
Fermentable fibres are consumed by the microbiota within the large intestine. They mildly increase the fecal bulk and produce short chain fatty acids as by products , which have wide ranging physiological activities.
Dietary fibres may also act on each phase of ingestion, digestion, absorbtion and excretion to affect cholesterol mechanism.
An important action of some fibres is to reduce the reabsorption of bile acids in the ileum and hence the amount and type of bile acids and fats reaching the colon.
