Definition and diagnostic criteria of clinical obesity.

Summary

An international Commission redefines obesity by introducing “clinical obesity” as a chronic illness due to organ/tissue dysfunction from excess adiposity and distinguishes it from “preclinical obesity.” It proposes objective diagnostic criteria that move beyond BMI alone, incorporating adiposity distribution and functional impairment.

Key Findings

• Defines clinical obesity as a chronic systemic illness due to organ/tissue dysfunction from excess adiposity.
• Differentiates preclinical obesity (excess adiposity without dysfunction) from clinical obesity (with dysfunction).
• Establishes objective diagnostic criteria beyond BMI, informed by a 58-member multidisciplinary, international panel including people with lived experience.

Clinical Implications

Clinicians should assess adiposity distribution and organ dysfunction (e.g., cardiometabolic, renal, hepatic, musculoskeletal) to distinguish preclinical vs clinical obesity and guide treatment intensity beyond BMI thresholds.

Limitations

• Consensus-based framework requires prospective validation and operationalization in clinical pathways
• Potential implementation variability across health systems and risk of misclassification without standardized tools

Future Directions

Develop and validate clinical tools and biomarkers integrating organ dysfunction metrics; test health and economic outcomes when applying the new criteria across diverse populations.