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Carbohydrates are made up of carbon oxygen and hydrogen molecules combined to form a molecule. There are simple carbohydrates like glucose, fructose while others like starch are more complex. Foods contain three types of carbohydrates; sugars, starch and fiber. Carbohydrates have a number of functions in living creatures. These functions are;
Carbohydrates as a source of energy
Carbohydrates provide us with energy required for proper functioning of our bodies. They are digested by the body and converted into glucose in human beings. This glucose is then converted into energy and used as fuel or if not required at the time it is stored for future use.
Lack of carbohydrates causes a person to experience feelings of fatigue, lowered endurance, trouble concentrating and poor mental functioning.
Fats and proteins can be burnt to produce energy however carbohydrates are the primary energy source. Fats are only burnt when there are no carbohydrates available or when the body needs long periods of sustained energy.
When fats are burnt without carbohydrates they produce toxic compounds known as keton bodies which if left to accumulate causes ketosis, a condition in which the blood is unable to carry sufficient oxygen with fatal results at times. Another function of carbohydrates therefore is to aid in the proper burning of fat.
Carbohydrates as food storage mechanism
Living things store carbohydrates for future use in different forms. Plants store food in the form of starch while garlic and onions store theirs as inulin.
In human beings carbohydrates which have already been broken down into glucose are stored as glycogen which is stored in the liver. When the body requires energy, this stored glycogen is converted back to glucose and used by the body for energy.
Carbohydrates as cellular structure building material
Carbohydrates in the form of polysaccharides act as building material for cells in many living things. Plant cells are made of cellulose, chitin forms cell wall in fungal cells and it is also forms the exoskeleton of arthropods while peptidoglycan forms cell wall in bacteria.
Other functions of carbohydrates
Carbohydrates also act as anticoagulants with heparin which is a polysaccharide preventing intravascular clotting.
They also act as antigen with many antigens being glycoprotein in nature. This gives blood its immunological properties
They also act as hormone with hormones like Follicular Stimulating Hormone (FSH) and Luteinizing Hormone (LH) being glycoprotein in nature.
Carbohydrate in the form of fiber such as cellulose, hemicelluloses, pectin, and mucilage help in the digestion process and also helps eliminate wastes and toxins from the body keeping it healthy. It does this by improving the constitution of one’s stool making it larger and softer and therefore requiring less force to expel.
Fiber also helps in prevention of intestinal diseases, reducing risk of becoming obese, it is also helpful in for people suffering from diabetes as it helps to slow absorption of glucose and as a result prevents sudden increase in blood sugar levels after meals. It also reduces the absorption of cholesterol and may help in preventing colon cancer.