So many fad diets that folks get confused and buy into the next new "system".
I would ask clients their current diets and they all thought they were eating good,but in reality the majority were atrocious.
Some got insulted when I critiqued them and that`s what they were paying me for. 
I believe that part of the issue is that children do not learn about nutrition from an early age. Not even the basics.
In elementary school, we learn about science, math, history, and english, etc. By the time we reach junior high or highschool, we have a basic understanding of these studies and are able to continually use them throughout our lives. But children never learn about nutrition, either at home or in school. The average parent knows jack shit about nutrition, so they wouldn't be no help. And school has dictated that certain topics (science, math, history) are more important than other topics (nutrition). Thus, there is a limit to what can be taught in school. So, the question remains: Where do children learn about proper nutrition, if not from home or school? Nowhere. We enter into adulthood not know anything about nutrition. Though, I believe in certain health classes nutrition is BRIEFLY covered, but nowhere near enough. If you don't teach these things at an early age, good luck trying to teach them during the teenage years.

I would be a proponent for some time during the school day to go toward teaching nutrition. It will never happen, but it would be a worthwhile endeavor.