There is nothing wrong with a little afternoon snack -- as long as it is not Doritos. (sorry!)
May I recommend a granny smith apple sliced up with a few shakes of cinnamon? Nutritious, tasty, and curbs the hunger pangs until dinner. Still feeling unsatisfied, fine, add all natural/unsalted peanut butter or almond butter too.
Added nutritional bonus: lots of antioxidants