To solve a problem you have to have reasonable knowledge of its cause.
In this case, I have my doubts that these folks do. I say this because when I was a kid, we ate much of the same stuff (or something similar) and almost no one was fat.
Actually we rarely ate out, fast food or otherwise. Soda pop was a rare treat. There were no video games, and we played all day after school until our moms called us home for dinner. In fact our moms wouldn’t let us stay indoors on nice weather days. Go out and play!