I have a few theories on this. Any additional insight would be appreciated.
It's turned into a vicious cycle, ultimately.
In the 1930's there was a senate hearing on the poor crop yield at that time. The reports (I'll be brief on this) pointed out a few problems, one of which was the de-mineralization of the soil. Chemistry was in the beginnings of its heyday, so the industrial chemists developed chemical fertilizer. They concluded that all a plant needed to grow was a few nutrients (nitrogen, phosporus, for example). These chemical fertilizers (with a few modifications) are what is still being used to this day. The other minerals (the ones that we need in trace amounts) were completely left out. The plants are able to grow, yet are lacking a great deal. Back then, we didn't realize all that the human body needs in small amounts to keep things in balance. Most people in this country don't realize that they are malnurished on a chemical level. When people aren't getting all that they need, the body responds by "craving." The problem is that we don't know what our bodies need. So we reach for what's convenient. It isn't fulfilling us, so we over-eat as a consequence. Hence, obesity.
The medical profession doesn't help either when they say that a normal balanced meal contains all of the nutrients needed. From what I understand (correct me if I'm wrong), but doctors take little, if any, nutrition classes in med school.
The problem is worse with our children, because they are trying to learn, yet lack the proper nutrients. And when the parents are clueless, they give the children what they eat which is garbage. So as a consequence, kids can't concentrate and act out. Parents take them to "experts" who then (usually with no blood test) put them on ridalin, prozac, buspar, etc. (Don't get me started on psychiatry)
Compounding the problem is popular culture and advertising. Turn on the idiot box, I mean TV and every other add is for an unhealthy food. Big macs and pizza are thrust at you. This reinforces poor diets. (Nothing healthy is ever advertised, only garbage you most likely don't naturally need. Ever see an ad for spinach?)
And when at last the human body is stressed and finally breaks, the person in it runs to a hospital and demands that we all "fix" them.
Don't mean to get on a soap box. I am only learning about nursing now, but I see the path ahead and understand the frustration that I will be confronted with.
Anything to add?