Earlier quoted context omitted.
Obesity is caused by eating too much of the wrong thing. Which happens to be the cheap thing in industrialized mass produced Western food chains. Cheap in terms of dollars and personal time. So obesity is really an economic problem. We should come down like a ton of bricks on fast food and require they offer healthier options at low prices, subsidized by taxes on their unhealthier options.
How many people are going to go to McDonald and order to tofu instead of the burger exactly? What's more the problem isn't the mere choice of the burger its the choice of the double burger with bacon, super sizing it, adding fries and lets top it off which a chocolate shake. For practical purposes you either need to eat modestly at McDonalds or more realistically not eat at McDonalds very much.
When we eat out, we easily eat 1000+ calories. That's over half the daily calorie budget of a 5'5 woman. Yet it's just one of the meals people eat in a day.
People like to come up with a bunch of reasons for why we eat too much or why the food we eat is somehow making us fatter than it might otherwise but we gloss over how trivial it is to overeat caloric dense foods even if "obesogens" and microplastics never existed.