Help Eating Disorder

As the title of my friend and roommate is sick, eat normal or below normal amount of food and then purging. For example. Yesterday he ate an apple and serve, just one block. I faced this problem and all it says is that "it is important that you know that I have no eating disorder, not a disease, something I do" I think I need to get your help, but I have no idea How? You're in a bedroom? Can we speak of a person or another RA in the dorm, and they know what to do? you can tell your parents? you can do. might say how you look and everything slips from time to time and eat well. " seek help for