Carbohydrate digestion
Carbohydrate digestion
Digestion in the human body is a very complicated and intricate process involving a lot of organs and chemicals. The main purpose of digestion is the breakdown of food and absorption of the nutrients. This provides for the energy and fuel that runs the body’s functions. Everyday we ingest a huge variety of food. We eat food depending on their taste, look and benefit. Due to this we are taking in a mix of various nutrients in different quantities. As part of the digestion process, these nutrients are absorbed and utilised for specific purposes. One of the most important nutrients that are required for energy requirements are carbohydrates. Carbohydrate digestion is a sub-process within the larger process of digestion. Carbohydrates are actually a class of substances including starch, sugars and cellulose. Carbohydrate digestion depends on what type it is and its molecular complexity. The digestive system has to work harder to break down more complex carbohydrates. Carbohydrates are mainly of 3 types: monosaccharides (glucose, fructose and galactose), disaccharides (sucrose, lactose and maltose), polysaccharides (lactose) and very complex carbohydrates like cellulose. In carbohydrate digestion, monosaccharides are most rapidly absorbed while cellulose is not digested at all. Because carbohydrates are so important to the body and because they are so many types of different complexities, the human body is designed to aid in carbohydrate digestion. Carbohydrate digestion begins right in the mouth. This is through the amylase secreted by the salivary glands. From the mouth, the food moves to the stomach. Here although the enzyme activity continues with carbohydrate digestion, the process is slowed down due to release of stomach acids. From the stomach the food (which is now in the form of chyme) moves to the small intestine. Here, as part of the carbohydrate digestion, amylase secreted by the pancreas act on the carbohydrates to break them down into simple molecules. Thus disaccharides and polysaccharides are broken down into monosaccharides. This makes absorption simple and glucose enters the bloodstream and is taken to the liver (where fructose and galactose are also converted to glucose) and stored or sent to different parts of the body that require it. Thus the liver regulates the amount of glucose in the blood stream. Any extra glucose is converted and stored in the form of glycogen. In case the sugar level falls, the liver reconverts glycogen into glucose and sends to different cells in the body. While simple carbohydrates are easily absorbed in carbohydrate digestion, cellulose is not digested at all and sent to the colon to be eliminated from the body. Thus carbohydrate digestion is as complicated as the process of digestion itself due to its complex nature and several types.
