I would take this issue kinda serious, if she continues this for a good amount if time, she could develop some serious problems. If you see that she is also afraid of non-fatty foods such as apples and bananas , I suggest you talk to your parents or people close to her. I have been in situations like this with some friends and their families and it can lead to emotional consequinses. If ya wanna, look for more advice at http://www.teenhealthfx.com/