By doing that, i've noticed that im not near as hungry during the day, and thus im less likely to snack around, especially with unhealthy foods like chips, sweets, etc. Then for lunch, I eat something easy like a bowl of oatmeal, or a protein bar. Sometimes even just a protein shake.
I do this as opposed to eating a bowl of cereal, and being hungry a few hours later, and snacking on useless foods and useless calories. Plus it gives me more time during the day to work off the calories, as opposed to a huge dinner, when all you do afterwards is sit around and eventually go to bed... and not really burning any of them off. This may not work for everyone and it's by no means perfect, but it's definitely working for me :)