A professor of technology once said to me, circa 2005, you don't need to know how a car's engine works to drive a car, and you don't need to know how a computer works to use one.
The next time your grandma fusses about how she can't "learn to do the computer," just tell her what my professor told me. (Unless of course she never learned to drive. Then you might be in for some trouble.)
It's critical at this point in our national, international, and societal development, that we extend that metaphor to food shopping, preparation, and consumption.
You don't have to be a nutritionist to realize that a Frappuccio is not coffee, but an ice cream milkshake. You don't have to be a liberal hippie vegetarian to figure out that instant mashed potatoes aren't vegetables. You don't have to be a locavore to decide that imported ingredients should be treated as luxury items, bought and enjoyed rarely rather than frequently.
What you do have to be is educated, willing and able to identify and ignore marketing and advertising practices — and education continues to be the major hurdle in fixing our global food problem. We have a lot of work to do poorer neighborhoods, where people are largely uneducated about these things.
On the other hand, there are plenty of educated people out there who are not thinking, acting, and eating wisely. My guess is they believe — whether they've thought about it consciously or not — is that shopping, preparing, and eating foods that will keep them healthy is too hard, too time-consuming, and outside their reach.
Wrong. Wrong. Wrong.
You don't have to be an expert to know what a vegetable is and is not. You don't have to be a nutritionist to glance at two labels and realize that the container of yogurt you've been feeding your children for breakfast is nearly equivalent, nutritionally, to a half cup of ice cream. You don't have to be a trained chef to put an inch of water in a pan, boil it, and add green beans, which your local grocery store will have already cleaned and sorted by size for even cooking times for you. You don't need two hours, or even 45 minutes, of extra time every night to tear up a head of lettuce (no knife required!), dribble on it vinegar and olive oil, and scramble two eggs.