Dietary fiber, also known as ROUGHAGE or bulk, is a type of carbohydrate that cannot be digested by the human body. It is found in plant-based foods such as fruits, vegetables, legumes, and grains. Dietary fiber helps to promote regularity, reduce cholesterol levels, and maintain a healthy weight. BRAN, which is a type of cereal grain, is a good source of dietary fiber. ROUGHAGE is another term for dietary fiber, and it is found in many plant-based foods.