How to Help A Friend With An Eating Disorder

If you have observed behaviors in your friend to roommate that are suggestive of an eating disorder, you are in a position to help that person.

Make a plan when you approach the person.
Present the situation in a caring but straight forward way. State what you have observed and what your concerns. Tell them that you are worried and want to help.
Give the person time to talk and encourage them to verbalize their feelings. Ask questions. Listen!
Do NOT argue about whether there is or isn't a problem! Power struggles will not help you at all!
Provide information about treatment. Offer to go with the person to their therapy.
If you are concerned that the eating disorder is a serious or life-threatening ask for the help of a doctor, therapist, etc. BEFORE you intervene
If the person denies that they have a problem, if they become angry, or if they refuse treatment, understand that this is often part of the illness. Besides, they have the right to refuse treatment (unless their life is in danger).
DO NOT try to be a hero or a rescuer, you probably will be resented. Do the best you can on several occasions, and remember that eating disorders are stubborn problems!
Eating disorders are usually not emergency situations. But, if the person is suicidal or otherwise in serious danger, GET PROFESSIONAL HELP IMMEDIATELY!