Using a triangulation framework—combining Mendelian randomisation, observational cohorts, and randomised trials—Sattar and colleagues at Glasgow make the case that excess adiposity causally drives at least six disease domains: musculoskeletal, metabolic, cardiovascular, mental health, respiratory, and hepatic. The strongest trial evidence for weight-loss as disease modification exists for type 2 diabetes remission and heart failure with preserved ejection fraction (HFpEF). Incretin-based therapies—semaglutide (GLP-1 agonist) and tirzepatide (GLP-1/GIP dual agonist)—now achieve 14–20% body-weight reduction in non-diabetic populations, generating the first large-scale randomised proof-of-concept across several morbidities simultaneously.
This perspective arrives at a pivotal moment. The cardiovascular outcomes trial SELECT established semaglutide's 20% MACE reduction independent of glycaemia, and SURMOUNT-OSA demonstrated tirzepatide's impact on obstructive sleep apnoea—collectively shifting obesity pharmacotherapy from symptom management toward genuine disease interception. The triangulation methodology the authors advocate is methodologically sound, guarding against confounding that plagues observational obesity research. However, this is a review article, not primary data, which limits direct actionable conclusions. Critical gaps remain: most trials exclude advanced disease stages and diverse ethnic populations, and durability of benefit upon drug cessation is poorly characterised. For clinicians and health-conscious adults, the practical implication is substantial—achieving ≥15% weight reduction, whether via pharmacotherapy or surgery, may constitute a unified disease-modifying strategy rather than addressing each comorbidity separately. This reframing from obesity-as-risk-factor to obesity-as-modifiable-disease-driver is incrementally confirmatory but clinically paradigm-shifting in its therapeutic scope.
