If you've heard of the movie Food Inc., go see it, and if you haven't heard about it, go see it! It's a documentary about the food industry in America, and it really made me stop and think, more than a movie has in a long time. It talks about the giant monopolies that control most of our food, how quality is no longer important, and how all of it has remained hidden from the public, but I couldn't accurately describe it, so check out the website for the movie.
also, check out the trailer. i would advise anyone to see this movie, it was very well done.