Oat bran is the outer layer of the oat grain, specifically the part that surrounds the seed. It is rich in dietary fiber, particularly beta-glucan, which can help lower cholesterol levels and improve heart health. Oat bran is often used in cereals, baked goods, and as a topping for yogurt or smoothies. In addition to its fiber content, oat bran is a good source of vitamins and minerals, including B vitamins, iron, and magnesium. It can aid in digestion and promote a feeling of fullness, making it a popular choice for those looking to maintain a healthy diet or manage their weight.