Digestion and Absorption of Carbohydrates
Absorption Mechanisms in the Small Intestine
The digestion and absorption of carbohydrates occur primarily in the small intestine, involving enzymatic breakdown and specialized transport mechanisms. Efficient absorption ensures optimal energy metabolism.
Digestion and Absorption of Carbohydrates
Introduction
Carbohydrates are an essential component of the human diet, providing the primary source of energy for bodily functions. Their digestion and absorption occur predominantly in the small intestine, involving a series of enzymatic and transport mechanisms.
Carbohydrate Digestion
Role of Salivary Amylase
Digestion begins in the mouth, where salivary amylase initiates the breakdown of starch into maltose and dextrins.
Pancreatic Enzymes
In the small intestine, pancreatic amylase continues starch digestion, converting polysaccharides into oligosaccharides and disaccharides.
Absorption Mechanisms in the Small Intestine
Sodium-Glucose Co-Transport
Glucose and galactose are absorbed via sodium-dependent glucose transporters (SGLT1) in the enterocytes of the small intestine.
Facilitated Diffusion
Fructose is absorbed through facilitated diffusion using GLUT5 transporters.
Clinical Implications
Defects in carbohydrate digestion and absorption can lead to malabsorption syndromes, such as lactose intolerance or glucose-galactose malabsorption.
Conclusion
The efficient digestion and absorption of carbohydrates ensure optimal energy supply to the body, highlighting the importance of enzymes and transport mechanisms.