It should at least have 4 types of food: carbs (carbohydrates), proteins, vegetables, and fruits. Be conscious about what types of foods to put in bento box when you are packing lunch. My children’s bento ratio is 4 : 2 : 1 : 1 (4 parts carbs : 2 parts protein : 1 part vegetables : 1 part fruits). I sometimes pack 2 parts of veggies inside the bento (skip fruit section) and prepare a separate container just for fruits.
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