alt Hacker NewsI think it's less about that farmer's market produce being healthier, and more about it being tastier. I've encountered plenty of people saying things like "I don't like tomatoes" when it turns out all they've eaten are pale, out-of-season tomatoes from the supermarket.
A big part of getting people to eat better is educating them about seasonality and what good produce should taste like, so that they end up actually liking it.
A farm by our cottage had a sign out last year, selling vegetables. We bought some cauliflower and had it for dinner. It was supposed to be a side dish but it was so darn good I don't even remember the main dish.
Later I got some vegetables from a friend who had grown them at a local allotment garden. Made some vegetable soup with them and I swear it's one of the best meals I've had, and I've had some real nice meals.
Flavor in each case was so far beyond what I can get in the grocery stores here it's hardly comparable.