@digitS' .
I'd say the problem runs quite a bit deeper, down to a nearly fundamental level. Namely, a society that places maximizing personal pleasure as the end all be all goal in life. From birth, we are taught not only that "if it feels good, do it but "if it feels good, do more and more of it until it doesn't." Control and temperance have basically become dirty words, and frugality and asceticism is practically looked on as a mental illness. And with a value set like that, OF COURSE you are going to wind up with health problems aplenty. And once we get those problems and need to do something about them, we are so hardwired to demand endless pleasure that we spend most of our time trying to figure out ways to "cheat" and get away with it. And the whole food industry is right there to help us with that cheating by misleading and misrepresenting things in an effort to sell more of them.
We try and make half hearted attempts to teach children how to eat healthy and get regular exercise, but what we probably REALLY need is to instruct them in a moral philosophy that makes some things MORE important than personal pleasure and, indeed, casts personal pleasure as a BAD thing to be minimized and eliminated as much as possible in favor of things like ones duty to others to be of maximum usefulness. Children need to be taught that, not only are they they not the center of the universe, but, in the grand scheme of things, they don't really matter at all, and that the decisions they make should be based not on how much benefit it will be to them, but how much benefit it will be to others.