Oat bran is the coarse outer layer of the oat groat. It concentrates much of the grain's beta-glucan, a soluble fiber that forms a gel in the gut. This gel binds to bile acids, which prompts the body to draw more cholesterol from the bloodstream for bile production. The same viscous action slows how quickly carbohydrates enter your system during a meal, blunting sharp rises in blood sugar after you eat.
Each tablespoon of oat bran delivers roughly 2 grams of fiber. Sprinkle it onto yogurt, blend it into smoothies, or cook it as a hot cereal. Start with small amounts to let your digestive system adjust, and drink plenty of water throughout the day to help the fiber do its job.