According to registered dietitian and nutrition consultant Shannon Crocker, eating 1/2 to 3/4 of a cup of cooked oatmeal every day is an easy way to give your body long-lasting energy. It keeps you feeling full longer than many other breakfast cereals because it takes longer to digest -- a definite plus if you're trying to lose weight or maintain a healthy weight. And whole grains have been shown to lower blood cholesterol and reduce your risk for diabetes and cancer.