Dietary fiber is a specific group of complex carbohydrates (derived from plant materials) which can not be digested by human digestive system.
Different types of fibers are present and they can be grouped into two broad categories i.e. water soluble fibers and insoluble fibers.
Soluble fiber- As the name suggests they are soluble in water. The influence of soluble fiber on digestive system is related to their ability to hold water and form gel matrix. This is directly related to the sense of satiety provided by these fibers.
Insoluble fiber- As the name suggests they are insoluble in water. Their properties are due to their indigestibility and fibrous nature. They stimulate the chewing action of jaws and enhance the saliva and gastric juice production. Insoluble fiber holds water to produce softer, bulkier stools.
By promoting better regularity, a diet high in insoluble fibers helps relieve constipation and control diverticular disease. Insoluble fibers may also help in preventing colon cancer.