The key to nourishment and having energy is to eat in "threes." Have something from three food groups, for three meals a day: a PROTEIN serving, a GRAIN serving, and a FRUIT OR VEGETABLE serving.
These three groups are a magical combination for energy and health. Just as long as you eat them in small quantities, like one or two small servings, for three meals a day.
Have only a little; there's never a need to stuff yourself when you're eating in balance. You won't feel hungry because you're giving your body exactly what it needs, when it needs it (throughout the day).
In my book and videos, "The Joy of Weight Loss," I also recommend eating every two to three hours in order to avoid ravenous hunger.