Tomatoes or cucumbers will do. Tomatoes are rich in vitamins, and cucumbers don't have too many calories, so you can eat them at night. Apples are too high in sugar to eat at night. It is best to eat apples in the morning to absorb them, and you can also supplement appropriate vitamins. If you can't stick to these two things, you can also drink some milk or yogurt, so that you won't be too hungry, get fat and have a good sleep. I wish you early success.