Mechanisms of postoperative anorexia in surgical patients: a narrative review

Postoperative anorexia is a highly prevalent condition among surgical patients, which exerting a profound impact on their recovery trajectories and nutritional status. The underlying mechanisms are complex and multifactorial, including neuroendocrine dysregulation, activation of inflammatory signaling pathways, and the interaction between psychological processes and pathological conditions. Emerging evidence underscores the significant role of altered hunger and satiety perception, cognitive modulation of food-related cues, and emotion-driven behavioral responses in the regulation of postoperative appetite. Despite these insights, there are currently no definitive targeted interventions available to effectively restore appetite in the postoperative setting. This narrative review summarizes recent advances in the understanding of appetite regulation, delineates key biological and psychosocial factors contributing to postoperative anorexia, and systematically synthesizes current clinical assessment approaches, and discusses emerging therapeutic strategies. By integrating insights from physiology, cognition, and affective science of postoperative anorexia, this narrative review seeks to provide a comprehensive understanding of the pathogenesis, assessment, and the current therapeutic strategies of postoperative anorexia.