I've read breakfast should be within the first two hours of waking up--but not necessarily the MOMENT you wake up--your body is still going from sleep mode to awake mode and your digestive system isn't necessarily ready to even take in food just yet. If you're full--don't eat, that's pretty key. So while it would be good for you to get in the habit of having something to eat (be it some fruit, some oatmeal, a smoothie, leftover pizza..) as breakfast, you don't need to STUFF yourself. At first, if your body isnt used to getting any food until later in the day you'll find you wont be hungry in the morning, so all you'll eat is maybe a small apple or a granola bar. Over time though you might get more used to spreading food out and you'll end up eating more and more in the morning.