Functions of Carbohydrates

FUNCTIONS

Providing energy is the major function of carbohydrates. Each gram of carbo-hydrate provides 4 calories. The body needs to maintain a constant supply of energy. Therefore, it stores approximately half a day’s supply of carbohydrate in the liver and muscles for use as needed. In this form, it is called glycogen.

Protein-sparing action is also an important function of carbohydrates.When enough carbohydrates (at least 50–100 g/day) are ingested to supply a person’s energy needs, they spare proteins for their primary function of build-ing and repairing body tissues.

Normal fat metabolism requires an adequate supply of carbohydrates.If there are not enough carbohydrates to fulfill the energy requirement, an abnormally large amount of fat is metabolized to help meet it. Dur-ing such an emergency need for energy, fat oxidization in the cells is not complete and substances called ketones are produced. Ketones are acids that accumulate in the blood and urine, upsetting the acid-base bal-ance. Such a condition is called ketoacidosis. It can result from IDDM(insulin-dependent diabetes mellitus), also known as type 1 diabetes, from starvation, or from extreme low-carbohydrate diets. It can lead to coma and even death.

When sufficient carbohydrates are eaten, the body is protected against ketones. This is sometimes called the antiketogenic effect of carbohydrates.

Providing fiber in the diet is another important function of carbohydrates.Dietary fiber is found in grains, vegetables, and fruits. Fiber creates a soft, bulky stool that moves quickly through the large intestine.