Oatmeal can help you lose weight in two ways. First, it's packed with fiber and it keeps you feeling fuller longer. Second, a recent study in the Journal of Nutrition reported that eating a breakfast made with "slow-release" carbohydrates—such as oatmeal or bran cereal—3 hours before you exercise may help you burn more fat. How? Eating "slow-release" carbohydrates doesn't spike blood sugar as high as eating refined carbohydrates (think: white toast). In turn, insulin levels don't spike as high. Because insulin plays a role in signaling your body to store fat, having lower blood sugar levels may help you burn fat.