How much muscle do you lose on semaglutide?

Clinical trial data shows 25-40% of total weight loss on semaglutide comes from lean body mass rather than fat. In the STEP 1 trial, DEXA analysis revealed 33-39% of weight lost was lean mass. The proportion varies by individual factors including protein intake, exercise, and baseline muscle mass.

Can peptides prevent muscle loss on GLP-1 drugs?

Peptide clinics are using growth hormone secretagogues like ipamorelin/CJC-1295 and MK-677 alongside GLP-1 drugs to protect lean mass. A small 2026 UCLA pilot study (n=34) showed patients retained 4.2 kg more lean mass with the combination, but large-scale RCT data does not yet exist.

What is GLP-1-induced sarcopenia?

GLP-1-induced sarcopenia refers to the significant loss of skeletal muscle mass caused by GLP-1 receptor agonists like semaglutide and tirzepatide. Because these drugs suppress appetite, patients often consume inadequate protein (40-60g/day vs. the recommended 1.2-1.6 g/kg), accelerating muscle breakdown alongside fat loss.

Which GH secretagogue is best for muscle preservation with GLP-1?

Ipamorelin combined with CJC-1295 is the most commonly used combination among peptide clinicians. It stimulates pulsatile growth hormone release without cortisol or prolactin spikes. MK-677 (oral) is a simpler alternative but can stimulate appetite, which may partially counteract GLP-1 effects.

Does tirzepatide cause less muscle loss than semaglutide?

Tirzepatide (Mounjaro/Zepbound) shows roughly 30-33% lean mass loss as a proportion of total weight lost in SURMOUNT trials, slightly better than semaglutide at 33-39%. However, because tirzepatide produces greater total weight loss, the absolute muscle loss may be comparable.

How much does a peptide-augmented GLP-1 protocol cost?

A peptide-augmented GLP-1 protocol from a concierge clinic typically costs $3,000-5,000 per month, compared to $1,200/month for GLP-1 medication alone. The added cost covers ipamorelin/CJC-1295 ($150-300/month), DEXA body composition monitoring, and clinician oversight.

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GLP-1 Muscle Loss: 40% of Semaglutide Weight Is Lean Mass

Up to 40% of GLP-1 weight loss is lean mass, not fat. Inside the sarcopenia crisis and how peptide clinics fight back with GH secretagogues.

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