I would say by being assertive. Let me know if I'm wrong
Kids don't lack control over what they eat their brain constantly gives a signal of more food engaging the kid to act that way. Children don't have physcial activity as well and sit on electronic devices all day and snacking not only causing health problems but as well less socially involved throughout the community. Vending machines are a killer to children providing unhealthy snacks for students to snack upon causing exclusive health problems on a everyday basis. Vending machines are a killer towards children providing unhealthy food towards their health.
Follow a food guide. For example, in Canada we have Canada's Food Guide that lists recommended foods in order to meet nutritional requirements for different ages and genders.
Hope this helps!
