Nature, Published online: 11 November 2026; doi:10.1038/d41586-026-03425-0

A framework for diagnosing obesity that was proposed in 2025 incorporates waist circumference and related measures and distinguishes clinical from preclinical obesity on the basis of obesity-induced organ dysfunction. In an international multi-cohort study of 844,108 adults, this framework outperformed conventional body-mass-index-based criteria in diagnosing obesity and stratifying mortality risk.