Provide Energy
All your activities need energy. Even a simple activity like walking or even breathing needs energy. The main source of energy required for your daily requirements comes from glucose. The source of glucose is from the starches and sugars you eat. Starches and sugars get broken down to simple sugar with help of insulin during the process of digestion. Glucose is then enters the cell wall. The extra sugar available from food gets stored muscles, liver, or other parts of your body. This then gets converted in fat later.