If it’s above your maintence cals then you’ll gain and if it’s at maintence then you stay the same weight if it’s under you’ll lose weight Because your body needs a certain amount of cals to be able function properly and the maintence cals are just the right amount of Cala your body needs to just be at a maintence. You will lose if you are about 500-1000 Cals below your maintence cals you should lose one pound of fat in 1 -2 weeks If you eat about 350 Cals above your maintence cals then you would gain an extra pound about every 10 days.