The problem of processed foods are not additives and preservatives, it’s mostly sugar. And since we all can agree that switching to balanced diet or clean food is a no go for poor people, the most likely change is in the junk food industry itself.

There’s a great piece on this topic from Atlantic: https://www.theatlantic.com/magazine/archive/2013/07/how-junk-food-can-end-obesity/309396/