My girlfriend can not eat more then a few bites, and at times goes as long as she can without eating, because eating anything causes her to become severely nauseated. She told me it started at a time that her parents were fighting frequently in her youth, and ever since she can barely consume anything other then a can of soup without feeling like she has to vomit. If her mother cooks she prefers not to eat, because she feels like she has to vomit if she has the smallest morsel of anything whole. However, every once and a while she can consume a large burger from a fast food joint without as much of an uneasy feeling.