Background <p>Anorexia Nervosa (AN) was first classified 150 years ago, although descriptions of pathology consistent with the illness can be traced as far back as the Hellenistic era and the Middle Ages. Despite decades of clinical theorising and a wide range of treatment approaches, recovery rates remain very low. In light of the limited efficacy of current therapeutic paradigms, there have been growing calls to critically reassess the taxonomy and conceptualisation of AN. This narrative review paper traces the evolution of theoretical frameworks surrounding AN, from early historical accounts in the 4th Century BCE to contemporary models. By examining these shifting perspectives, the paper aims to provide a foundation for renewed inquiry into the phenomenology of the illness and to support the development of more effective, nuanced approaches to treatment and understanding.</p> Method <p> PubMed and Scopus databases were searched for relevant articles. Additional articles were identified through references in published studies. Abstracts were screened for relevance and studies were included if their design and findings addressed theory of illness or phenomenology in AN.</p> Discussion <p>AN has been viewed over time through psychodynamic, family systems, feminist and evolutionary lenses, among others. The conceptualisation of the illness is historically fragmented, shaped by shifting cultural, medical, and psychological paradigms rather than a linear theoretical progression. Modern understanding recognises AN as biopsychosocial yet lacks a unified, coherent model and mostly treats under a psychological paradigm. Dominant therapies like FBT and CBT-E show modest outcomes and high dropout rates, reflecting deeper issues in theoretical alignment and treatment efficacy. Calls for an integrated, individualised framework stress the need for empirical, multidisciplinary theory to support flexible, evidence-based treatment innovation.</p>