If you google it you can find lists but the basic theory is that some foods have less calories than your body uses to digest and excrete them.
Celery, cucumber, apples, grapefruit, lettuce, watermelon.......

I'm not 100% sure if they really do use more calories than they provide but they certainly won't make you gain much weight.
Carrot and brocoli are 2 big negative foods... blueberries (in fact most berries) and watermelon are too.

Eat more during the day. If you are starving and snacking heaps at nighty your body needs more food during the day. This is my downfall, eat barely anything during the day and i get soooo hungry at night! Lunch should be the biggest meal of the day so try having a big lunch with some carbs, protein and lots of veggies, then have some fruit too... See if that makes a difference?