A narrative/updated review of 40 DXA-based reports evaluating changes in body composition (% fat-free mass lost, % FFML) with GLP-1 receptor agonist–based agents for obesity treatment.
Across 40 DXA-based reports, mean % FFML was 29.1% (SD 19.0%), placing GLP-1 RA–based agents in the upper range of expected fat-free mass loss (~25% with diet alone) seen with other nonsurgical obesity interventions.
- Findings are based on a narrative review without meta-analytic pooling; high SD (19.0%) signals substantial variability across studies. - Functional outcomes (strength, physical performance) were not assessed, leaving gaps in clinical relevance. - High-risk populations (e.g., older adults, sarcopenic individuals) are underrepresented in included reports.
GLP-1 RAs produce fat-free mass loss at the higher end of what nonsurgical obesity treatments typically cause (~29% vs. ~25%), so clinicians should consider monitoring muscle mass and function—especially in older or sarcopenic patients. Functional strength and performance data are still needed to fully judge clinical impact.
