Obesity redefined: clinical versus preclinical
A 58-member Lancet Diabetes & Endocrinology Commission proposed confirming excess body fat directly rather than relying on BMI alone, then separating clinical obesity (organ dysfunction or limited daily activity) from preclinical obesity (preserved function, higher risk).
EVIDENCE
Expert consensus
WHY IT MATTERS
It reframes care around what excess fat is doing to the body, which helps decide who needs medicines or surgery now and who needs monitoring and risk reduction.
The details
Excess adiposity can be confirmed with BMI plus a body-fat measure such as waist circumference, with two body-fat measures, or with direct measurement such as DXA. The Commission lists 18 diagnostic criteria for clinical obesity in adults.
Major groups including the Obesity Society and the Obesity Action Coalition endorsed the report, though questions remain about how to apply it in routine practice.
PRIMARY SOURCE
Rubino F et al., Lancet Diabetes Endocrinol 2025;13(3):221–262
Lancet Commission on Clinical Obesity
Educational summary only. It is not medical advice and does not replace a conversation with your clinician.