Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Table sugar, granulated sugar, or regular sugar, refers to sucrose, a disaccharide composed of glucose and fructose. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Sugars are an important source of energy with glucose being the most important for the body. The brain requires around 130 grams of sugar (glucose) per day to keep functioning. Glucose can be found in a range of foods including fruit, vegetables and honey.