Importance of the dietary fibers was discovered only few years ago. Although Hippocrates commented about the laxative effect of the dietary fiber only few individuals paid attention to the dietary fiber. Only in the 19th century proper medical experiments about the dietary fibers started. After that scientists recognized the importance and the benefits of the dietary fibers with some questionable results.
Definition of the dietary fiber:” All polysaccharides and lignin in the diet that are not digested by the endogenous secretions."
So this definition includes polysaccharides and lignin in skeletal frame work of plant cells as well as some food additives.
Chemical composition of dietary fiber
Effects on gut physiology
Dietary fiber has marked influences on the gut physiology.
Mainly dietary fiber is responsible for the increase in stool bulk. It also slows the glucose absorption and prevents post prandial hyperglycemia. This may be achieved by interfering the carbohydrate metabolizing hormones like amylase, sucrase. So the intake of dietary fiber has beneficial effects for the diabetic patients. Dietary fiber known to decrease lipid absorption and increases faecal lipid content. It also reduces the blood cholesterol by reducing the re absorption of bile salts in the ileum.
Problems associated with high dietary fiber intake
With all the benefits dietary fibers have some disadvantages. Dietary fibers reduce the absorption of some minerals, like; Iron, Calcium and Zink. So this may put people with marginal mineral intake at risk. So people should be encouraged to increase the mineral intake along with the dietary fiber.