1. Refusal to maintain body weight at or above a minimally
normal weight for age and height (eg. weight loss leading
to maintenance of body weight less than 85% of that
expected, or failure to make expected weight gain during
period of growth, leading to body weight less than 85% of
that expected)
2. Intense fear of gaining weight or becoming fat, even
though underweight
3. Disturbance in the way that body weight, size or shape is
experienced, undue influence of body shape and weight on
self evaluation, or denial of the seriousness of current low
body weight
4. In postmenarchal females, amenorrhoea, ie. the absence of
at least three consecutive menstrual cycles