Stop producing junk food and bad food and almost poisenous food. That simple: what is not availablel cannot be eaten, cannot ruin people's health.there are some things were this is all so ovvious and evident.
Problem is not how much you eat. Problem is what it is that you eat. If you eat the "right" things (
hypoglycaemic carbon hydrates), and avoid the "wrong" things (
hyperglycaemic carbon hydrates) you can eat as much as you want, since your insuline production remains low and most of the carbon hydrates do not end up in being transformed into energy reserves and being added to your body's fat reservoirs.
the link between type of carbon hydrates, insuline production and fatness is so very simple and easy to understand, really.
Now how do we solve this existential problem of bad stuff being so damn tasty? 
Probably no solution. So, better don't produce it from the very beginning.
