Study leave & Snacking all day long!

it doesn't look like anyone posts/reads here anymore.. but,

How do you guys keep to plan on revision/study leave? If I'm busy with classes I can handle it.. but me in the library or at home all day .... its just so hard! At the library I just run to the store to reward myself for however many hours study I have done... Food is better at home as I don't keep junk in the house (but I do get less work done!)

If anyone has any tips for me on how to combine dieting with revision and not be completely miserable... or worse fail exams.. or not be able to concentrate due to just thinking about food (i'm not even hungry, I eat properly its boredom... bored of studying!)

Anyway, thank you & Happy New Year!