Constitute more culture places in the world,
The main issue is that people eat fast food and processed garbage that's high in calories and is actually designed to make you not feel full,
If everyone cooked traditional home cooked meals, you'd see a shard decrease in obesity,
there also needs to be more shaming for being overweight,
Being overweight isn't even considered a bad thing anymore by most people, it's considered brave and good.
We need people to call each other fat and fat asses, these people need to feel hurt and pushed to lose weight, for their health.
Also, a large amount of the population sits all day as well, we need to encourage people to become more active, it doesn't even have to be traditional exercise, most people back in the day burned probably 1000 calories plus, walking around all day and doing small tasks.