This can arise from consuming too much of any one food every day.
Wheat and sugar are the main culprits, especially if the wheat is refined, depleting it of nutrients and processed into pasta, pastry, pizza, pies, noodles, spaghetti, cakes, scones, biscuits and more. These deprive the appetite of nutritious food, rob the body of nutrients and contribute little except calories, setting up cycles of overeating. Fruit juices have too much sugar and salicylates in one hit, especially damaging in children. Juice may be a natural food but it is not natural to consume the liquid from 12 oranges in one glass. Fibre slows the absorption of sugar so that it doesn’t flood the blood- stream.
The answer here is to widen the variety of food, target those that are rich in nutrients and go for a whole - whole grain, whole fruit. You can easily list 20 vegetables for a start and many are cheap to buy in bulk eg. potatoes, carrots and onions. Some are very easy to grow, even in a pot or bucket eg. herbs like flat leafed parsley, silver beet, lettuce.
And remember that ‘water kills the meanest thirst’ and it’s FREE!