Physiological importance of dietary fiber
- Stimulates chewing and thus saliva flow and gastric juice secretion.
- Insoluble fibers increase the fecal bulk by absorbing water thus decreasing the pressure on the walls of the colon. This helps in preventing constipation and diverticulosis (small herniations in the mucous membrane of the colonic wall).
- ” Normalizes” intestinal transit time.
- Soluble fibers such as guar gum, oat bran, legumes etc. may help in reducing the total cholesterol, specifically the low density lipoprotein (LDL) cholesterol.
- Soluble fibers may also help in controlling blood glucose levels. The presence of soluble fibers reduces the efficiency of enzyme hydrolysis in the gut thereby reducing the rate of absorption of glucose.