BACKGROUND Currently, there is limited understanding of the etiology of BN. While multifaceted etiology is likely, several neurobiological factors may play a role. Brain derived neurotrophic factor (BDNF), a potential biomarker linked to eating and weight disorders, is one factor of recent investigation. This paper examined studies comparing BDNF blood levels in BN to healthy control (HC) subjects. METHODS A systematic review of the literature was conducted utilizing five databases (PubMed, CINAHL, EMBASE, PsycINFO, and Medline). Key terms included eating disorders, BDNF, and bulimia nervosa. CONCLUSIONS BDNF blood levels appear lower in BN than in HC subjects; however, studies are needed to examine the influence of possible correlates including symptom severity, mood, medications, exercise, and substance use.