For a book I'm writing about the Local Food movement, I tried eating only local food for a month. Eating mostly from farmers' markets and a weekly delivery from a local farm, I was amazed how vibrant the flavors were. Of course, you'd expect fresher food to taste better, but I also discovered it's better for you. In the course of my research I came across a study showing that spinach lost half its foliate - a type of vitamin B -- after eight days of storage at 39 degrees. That's pretty significant since it can take spinach longer than that to get from the field to the supermarket. Farmers market food, on the other hand, is typically picked the night before.