Have more than a hunch about your lunch.

You take a break in the middle of the work day to eat, right? Be intentional about your plan and you'll be less likely to improvise (unhealthily, I might add) when it's time to eat. Try to prepare your lunch in advance. Crock-Pot makes some fantastic personal-sized warmers, too: there's nothing better than piping hot food when you're ready for it.