Fuel toxicity-associated spectrum (FTAS): a unifying nomenclature for metabolic disorders

The global obesity surge has precipitated a parallel rise in diabetes, cardiovascular, kidney, and reproductive-metabolic diseases like polycystic ovarian syndrome (PCOS), creating an unsustainable healthcare burden fragmented by organ-specific nomenclature. Legacy terms like type 2 diabetes and non-alcoholic fatty liver disease (NAFLD) focus on end-stage manifestations, obscuring shared pathogenic roots. This review aimed to propose and define the Fuel Toxicity-Associated Spectrum (FTAS) as a unifying nomenclature and staging framework for adiposity-related metabolic disorders. This represents a novel conceptual synthesis building upon established pathophysiological principles. We conducted a narrative review, synthesizing literature on the pathophysiology and nomenclature of adiposopathy associated metabolic conditions to build a logical argument for this new mechanistic classification. We propose that the FTAS framework reconceptualizes disorders from metabolic syndrome to overt organ damage as manifestations of a single pathophysiological process: chronic nutrient excess driving adipose tissue dysfunction and systemic fuel toxicity (lipotoxicity, glucotoxicity, organelle dysfunction). We provide a unifying nosology, mapping legacy diagnoses to FTAS equivalents (e.g. type 2 diabetes to FTAS-Hyperglycemia) and integrates related constructs into a hierarchical model. A novel four-stage system (Stages 0–3) was formulated, representing a hypothesis that transcending organ silos facilitates a complication-centric approach to care. The review also outlines a proposed prospective validation roadmap and a phased implementation strategy for the framework. The FTAS provides a proposed holistic, pathophysiologically grounded, and destigmatizing lexicon that unifies metabolic conditions. It aligns with modern, metabolism-targeting pharmacotherapies and is hypothesized to transform clinical practice and research by promoting early, integrated intervention, though this requires prospective validation.