<p>Eating disorders (EDs), including anorexia nervosa, bulimia nervosa, and binge eating disorder, are severe psychiatric illnesses marked by disordered eating patterns and psychological disturbances. Post-traumatic stress disorder (PTSD), a common response to trauma, is characterized by re-experiencing, avoidance, negative alterations in cognition and mood, and hyperarousal. The prevalence of PTSD is significantly higher among individuals with EDs than in the general population. This comorbidity is associated with more severe clinical presentations, greater functional impairment, higher treatment dropout rates, and poorer prognoses. Despite increasing recognition of this co-occurrence, the underlying biological and psychological mechanisms remain inadequately understood. This review explores potential shared pathways from a biopsychological perspective, including dysregulation of the hypothalamic-pituitary-adrenal axis, immune system alterations, gut microbiota imbalances, emotional dysregulation, and dissociation. Current treatment strategies are reviewed, highlighting the lack of specific clinical guidelines for this population. There is an urgent need for integrated, trauma-informed interventions to enhance outcomes for individuals affected by the dual burden of EDs and PTSD.</p>