I just checked out Bethenny's website and she has some great advice on how to avoid the Freshman 15 (or Sophomore, Junior, Senior, Super Senior...). Since I'm currently a college student I know it can be easy for most people to gain wait quickly and lose it slowly. It's hard to take time out of a busy schedule and make a healthy meal! Since universities have just begun a new semester, get an early start and eat well!
And I'm totally about to give Bethenny some free publicity: So I've read Bethenny's Naturally Thin and Skinnygirl Dish and seriously they both are super encouraging. She hates the diet word, so she gives a new way to think about food. It definitely teaches you how to eat whatever you want and still lose weight. Try it-it's awesome stuff!