Carbohydrates

Functions of Carbohydrates

The disease of having many diverticula in the large intestine is known as diverticulosis. Although diverticula is often asymptomatic, food particles become trapped in their folds and bacteria begin to metabolize the particles into acids and gases. Eventually, the diverticula may become inflamed, a condition known as diverticulitis. To combat the disease, antibiotics are administered to the patient to destroy the bacteria while the intake of fiber in the diet is decreased until the inflammation has subsided. Once the inflammation has been reduced, a high fiber diet is begun to prevent a relapse.

Besides the prevention of intestinal disease, diets high in fiber have other health benefits. High fiber intake reduces the risk of developing obesity by increasing the bulk of a meal without yielding much energy. An expanded stomach leads to satisfaction despite the fact that the caloric intake has decreased.

Beyond dieters, diabetics can also benefit from consuming a regular amount of dietary fiber. Once in the intestine, it slows the absorption of glucose to prevent a sudden increase in blood glucose levels. A relatively high intake of fiber will also decrease the absorption of cholesterol, a compound that is thought to contribute to atherosclerosis or scarring of the arteries. Serum cholesterol may be further reduced by a reduction in the release of insulin after meals. Since insulin is known to promote cholesterol synthesis in the liver, a reduction in the absorption of glucose after meals through the consumption of fiber can help to control serum cholesterol levels. Furthermore, dietary fiber intake may help prevent colon cancer by diluting potential carcinogens through increased water retention, binding carcinogens to the fiber itself and speeding the passage of food through the intestinal tract so that cancer-causing agents have less time to act.

Biological Recognition Processes

Carbohydrates not only serve nutritional functions, but are also thought to play important roles in cellular recognition processes. For example, many immunoglobulins (antibodies) and peptide hormones contain glycoprotein sequences. These sequences are composed of amino acids linked to carbohydrates. During the course of many hours or days, the carbohydrate polymer linked to the rest of the protein may be cleaved by circulating enzymes or be degraded spontaneously. The liver can recognize differences in length and may internalize the protein in order to begin its own degradation. In this way, carbohydrates may mark the passage of time for proteins.