Take notice of any changed behaviour in your friend. Unexplained changes in moods, socialising, style of clothing and even how they talk about themselves could all be indicators that something is seriously wrong.
Be prepared for friends' little white lies.
It is difficult to recognise signs of a presenting eating disorder. However, through 'listening' to the conversation with your friend, looking deeper into what is actually being said, your powers to detect may be sharpened.
"I baked some cupcakes today but I don't really fancy them now."
"I don't want to eat any fattening foods."
"I absolutely love dancing. I dance all night when I'm clubbing. I love it."
"Fantastic way to hide my eating disorder...and burn more calories."
"I won't eat yoghurts. I think I'm allergic to dairy products."
"I'm restricting my food types."
Changed behaviour towards food and drink
If you suspect your friend has an eating disorder:
Be yourself, be open, honest and supportive.
Be attentive be prepared to listen.
Emphasise your friends qualities and positive characteristics, skills, strengths, talent.
Avoid being drawn into talking about food, calories, body size.
Encourage your friend to seek help of a professional if he/she hasn't done so.
Raise your concerns with a trusted responsible person, preferably an adult.
Do not give advice - remember you are not your friend's therapist.
Do not expect your friend to recover over a matter of days.
Do not blame yourself for your friend's condition.