If you eat two or three times a day, it means that your blood sugar undergoes more fluctuations, which can mean less energy and more readily deposited bodyfat. Plus your metabolism will keep revving because your body has to expend the effort to digest stuff more frequently. Fourth, learn to read labels to look for hidden sources of sugar . Soft drinks and juices are loaded with sugar. If you must drink pop, at least switch to diet.
Most breakfast cereals are pure junk from a simple carb standpoint.
Finally, and this is a corollary of the first thing, learn about the glycemic index . The body has to work harder to convert more complex carbs, protein, and fat to glucose.