Not good. You have to eat. Otherwise your body retains EVERYTHING. I've found the best way is to eat healthy to halfway decent, but also filling, small portions every four or so hours you're awake. That might mean a banana and a nutrigrain bar, or a peanut butter sandwich on wheat and water, etc. Eat enough that you're not hungry, but not too much that you're stuffed.
Whale cancer! Eff yeah!