Neurobiological and Metabolic Biomarkers as Diagnostic Tools for Anorexia Nervosa in Adolescents: A Literature Review

Anorexia nervosa carries the highest mortality rate of any mental health disorder, yet its early diagnosis in adolescents remains critically hindered by overlapping symptomatology, high comorbidity rates, and environmental factors. Moreover, as precision medicine gains traction, the lack of reliable biological indicators for this disorder remains a significant gap. This review synthesizes the current literature on neurobiological and metabolic biomarkers as prospective diagnostic tools for anorexia nervosa in adolescents, interpreting the findings into two categories: trait biomarkers, which reflect stable physiological predispositions detectable prior to symptom onset and often persist post-recovery, and state biomarkers, which emerge during active stages of the disorder. Key biomarkers examined include electrophysiological abnormalities, structural brain changes, neural network dysfunction, and metabolic dysregulation across amino acid, lipid, and hormonal profiles. The implications of applying biomarkers to clinical diagnostic procedures are further identified, alongside critical limitations and ethical concerns regarding this practice. This review highlights the need for longitudinal, demographically generalizable research in this field and the implementation of changes in healthcare policy to ultimately move toward a precision-medicine standard for the early detection of anorexia nervosa in adolescents.