The bran (also called miller's bran) is a hard outer skin that covers a grain from a cereal plant, for example wheat. It has a type of cell tissue called aleurone. It has a pericarp, which is the part of the grain that has the seed in it. With the germ and endosperm, this forms a whole grain. In a refined grain, this layer, and the germ is removed. This part has fibre and some micro-nutrients like iron and some B vitamins.