Research

Energy balance

Lean mass is an inaccurate proxy for muscle mass in GLP-1 trials because it includes organs, bone, and fluids; MRI-based muscle volume z-scores provide a more accurate assessment of muscle health.

Do not rely solely on 'lean mass' numbers from standard scales or DXA scans to judge your muscle health. These numbers include water and organ weight. For a true picture of muscle, look at muscle volume and quality via advanced imaging like MRI, which shows if muscle fat is decreasing.

StrongRefutesVERY_HIGH confidence
changes in lean mass may not always reflect changes in muscle mass as the former measure includes not only muscle but also organs, bone, fluids, and water in fat tissue.
Ian J. Neeland et al. · Diabetes Obesity and Metabolism · 2024

Why this rating

Well-established physiological principle supported by multiple citations.

Source

Changes in lean body mass with <scp>glucagon‐like peptide</scp> ‐1‐based therapies and mitigation strategies

Ian J. Neeland et al. · Diabetes Obesity and Metabolism · 2024

DOI 10.1111/dom.15728

narrative_reviewCited 285×
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DOI resolved against Crossref · corpus check 2026-06-10

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