Bf says he eats at midnight to be able to sleep. What are healthy things he can eat that help sleep but won't promote weight gain? Serving size pls

Health foods. nuts, fruits, vegetables. celery sticks, carrots and such. dont use dressing which can promote weight gain. drinking water instead of juices or sodas. .
Fiber, earlier. For this situation, I would recommend he eats a small meal (no more than 200 cal) that contains a large amount of fiber. However, he should eat this no later than eight or 9 PM. The hope would be that the fiber will keep him full and allow him to achieve a normal night sleep. Even a low-calorie high-fiber snack bar at that time of day would be fine.