I have a teenage son which has a tendency to always eating something or asking what is for supper? Even though I am making supper at the moment he is asking, he will still get a snack from the cabinet. There are many days where food is gone within a couple days after it is bought. We have made comments about our son eating us out of the house or he needs to get a job to pay for the food he eats. I have even told him to stop eating many a times. Even the simple things were eaten up fast like bananas or bread for sandwiches. He makes PBJ sandwiches a lot.
Do not fill the refrigerator or cabinets overly full with food. You will tend to be out of food within a couple days.
If you only go shopping only so many days a month, buy what you think you will need. Then hide certain things somewhere no one else will find. My husband has even his certain snack in the high cabinets in our kitchen.
Make some snacks from ingredients you have at home, some ingredients may need to buy. Possible suggestions are homemade granola bars, a snack mix, or cookies.
Shop at the Dollar Tree for cheap snacks and use coupons when you can.
Keep him active in sports or chores around the house so he is not laying around watching television. Doing nothing he will be drawn to snacking throughout the day.
Buy things that will make his stomach full.