We expect to find sugar in foods such as cakes and cookies, but other foods such as catsup and canned vegetables are full of sugar, too.
Sugars are a kind of carbohydrate.
Carbohydrates include sugars, starches, cellulose, and other compounds. An essential nutrient, carbohydrates are the body's main source of both quick and sustained energy. All carbohydrates have four calories of energy per gram of weight. As an example, one teaspoon of sugar equals 35 calories. Sugar is an energy source for the body.