another idea is to find ways to reduce your stress levels. Exercise is a great stress reducer, so putting that into your schedule is really important not just for your physical health, but for your emotional and scholastic health as well.
also, you do have some control of what you eat when you're on campus. sure, it's within strict parameters (what others provide), but you can still make healthy choices from what is available. I wouldn't do calorie restriction (you need it for good brain function), but i would look to consuming more healthy foods more often.
both of these things will help reduce overall stress too. oh yeah, and drink lots of water!