The crossword solution for the term 'Dietary Fiber Source' is 'BRAN'. BRAN is a type of cereal grain made from the hard outer layer of wheat, rice, or other grains. It is high in dietary fiber and is often used as an ingredient in breakfast cereals, breads, and other food products. BRAN is also a popular health food due to its high fiber content, which helps to promote digestive health and reduce cholesterol levels.