Breakfast is important because it jump starts your metabolism for the day. Your metabolism slows considerably while you sleep, and if you don't eat something soon after waking up, it will remain slow throughout the day, and you will be more likely to put on excess fat.
Right, which is why I mentioned protein.
A hard-boiled egg is a great way to get that (I just cook up a batch once a week), plus some whole wheat toast or some whole grain cereal. It only takes 10 minutes in the mornings, and since I started that routine, I've started feeling a
whole lot better until lunchtime. Works a hell of a lot better at keeping me going than coffee.