Review attributes 20-40% of GLP-1 weight loss to lean mass

The wire

1. 01An IJMS narrative review covering literature through June 2026 finds 20-40% of weight loss on GLP-1 and dual or triple agonists comes from lean mass.
2. 02For clinicians managing older or frail patients, the review stresses that lean-mass loss alone does not meet the definition of sarcopenia, which requires reduced strength and function.
3. 03Tirzepatide data are more limited than semaglutide, and the authors say current evidence cannot separate systemic energy-protein deficit from direct catabolic drug effects.

From the source

Skeletal Muscle Effects of GLP 1 Receptor Agonists: Molecular Mechanisms and Comparative Insights on Semaglutide and Tirzepatide, a Narrative Review

International journal of molecular sciences · 2026 Sep 10 · Cautela D, Incarbona V, Lombardi A et al.