It is good to do calorie zig zagging. Our bodies get used to the amount of fuel we give them and we need to keep it guessing. A good way to do this is to eat different amounts of calories every few days. For instance, eat around 1600 for two days in a row and then eat 1300 for the next two. So on and so on. Don't try to stick right at the same number, or you'll likely get stuck in a plateau.