ObjectivePrior research suggests that both body mass index (BMI) and weight suppression (highest past weight minus current weight; WS) are important in determining adult anorexia nervosa (AN) severity. We examined associations between amenorrhea and WS, DSM-5 BMI severity category, and highest premorbid BMI among patients with AN. MethodParticipants (N=69) were adult female AN-spectrum patients at two residential treatment facilities. At admission, height, and weight were measured, and participants completed questionnaires assessing menstrual status and weight history. ResultsGreater WS, adjusted for BMI, was associated with menstrual function at admission. First amenorrhea onset occurred at a normal BMI for 38.5% of participants. Premorbid highest BMI positively correlated with BMI at amenorrhea onset, and higher BMI at amenorrhea onset was associated with higher BMI at menses resumption. DiscussionThese findings add to the literature indicating that relative and absolute weight status are dual indicators of illness severity in AN, and preliminarily suggest that a large proportion of adults who present for treatment initially may have shown symptoms of starvation at a normal BMI. Results underscore the need to focus on weight loss in early detection efforts and may inform target weight setting in the treatment of AN.