Photographed by Ruby Yeh. What's the difference between "educated" and "obsessed"? How can you tell whether someone is just a health geek — or has reached unhealthy levels of food fixation? It can be hard to distinguish. Even if you don't exemplify a traditional eating disorder, preoccupation with food, diet, and nutrition can negatively affect your body and mind. There are three types of neurotic eaters who cross that blurry line between enthusiasm and compulsion. Are you or someone you know a Bird? A Punisher? Or a stuck-in-the-Nixon-era Seventies Dieter? Find out, after the jump. (Shape)