I've noticed when I eat bad I tend to feel bad, but that's connected to all sorts of junk. I've pondered giving up sugar, but it never quite works. There is a book called "Potatoes Not Prozac" that talks about sugar/carbs in connection to depression. It's a quick, easy read and I've thought of following it. My problem is when I'm really depressed (like now) giving up sugar just seems to overwhelming.