Carbohydrates are the starches and sugars in the diet that are used by the body primarily to supply energy. Carbohydrates is one of the six categories of ‘essential nutrients,’ substances the body is unable to make on its own, so they must be obtained from food. Carbohydrates have four calories per gram. ‘Complex’ carbohydrates are starches in their natural, unrefined form, such as whole grains, beans, vegetables, and fruits. ‘Simple’ carbohydrates include such things as alcohol, honey, sugar, and corn syrup, which are ’empty’ calories, calories without any nutritional value, fiber, or bulk. Refined sugar, in particular, has had the fiber and chemical warning signals that tell your brain you’ve had enough to eat removed during processing. Complex carbohydrates are more filling than simple ones and biochemically signal your brain that you’ve had enough to eat. They’re also higher in fiber and lower in calories and are hard for the body to convert to body fat, which keeps you slimmer. It also takes more calories for your body to digest and metabolize complex carbohydrates than it does to digest and metabolize simple sugars, which means you can eat more complex carbohydrates and put on less weight than when you eat other types of foods.