Functions of carbohydrates
The functions of carbohydrates in the body are as follows:
Energy: The principle function of carbohydrates is to serve as a major source of energy for the body. Each gram of carbohydrate yields 4kcal of energy regardless of its source.They provide an economical and quick source of energy. Excess carbohydrates in the body is stored as glycogen and can be converted to glucose for energy production when required .
Protein Sparing Action: Carbohydrates exert a protein sparing action. If sufficient amounts of carbohydrates are not available in the diet, the body will convert protein to glucose in order to supply energy. Hence, in order to spare proteins for tissue building and repair, carbohydrates must be supplied in optimum amounts in the diet. This is called the protein sparing action of carbohydrates.
Fat Metabolism: Adequate supply of carbohydrates determines the amount of fat to be metabolized for energy, which in turn affects the formation and disposal rate of ketones (intermediate products in fat metabolism). In the absence of adequate supply of carbohydrates, more fat is used because of which ketones accumulate in the body and this results in a disorder called Ketosis or Acidosis. This shows that carbohydrates have an anti- ketogenic effect which prevents harmful effect of ketone accumulation in the body.
Synthesis of Body Substances: Carbohydrates aid in the synthesis of non- essential aminoacids, glycoproteins (which function as antibodies) and glycolipids (which form a part of cell membrane in body tissues especially brain and nervous system). Lactose encourages the growth of favourable intestinal bacteria.It has laxative properties and enhances the absorption of calcium.
Detoxification: Glucuronic acid, a metabolite of glucose serves as a detoxifying agent. It combines with harmful substances containing alcohol or phenolic group converting them to harmless compounds which are later excreted. Adequate hepatic(Liver) glycogen storage enhances normal liver detoxification ability.
Roughage in the Diet: Insoluble fibres (Cellulose) known as complex carbohydrates can absorb water and give bulk to the intestinal contents which aids in the elimination of waste products by stimulating peristaltic movements of the gastrointestinal tract.
Central nervous system(CNS): Glucose alone can work as a source of energy for the central nervous system. Prolonged deprivation of glucose to the CNS may cause irreversible damage to the brain.