Research article on the Diagnostic tool for the treatment and control of diabetes Diabetes Diabetes is the bodys inability to convert glucose (sugar) to energy. Glucose is the main source of energy that our body needs to run the normal metabolic functions. After digestion, the food is converted into various forms such as protein, carbohydrates, or fats. Carbohydrates affect the level of blood sugar in the blood. Carbohydrates, after digestion, change to glucose. Glucose is then transferred to the blood and is used by the cells as the main source of energy.