Short-term liraglutide (18 days) selectively reduced android and trunk fat while preserving lean and bone mass, with decreased C-peptide and modestly increased IGF-1 in patients with type 2 diabetes.
Belly fat firstJust 18 days of liraglutide selectively reduced the most dangerous fat (android/trunk) while leaving muscle and bone untouched
What the researchers found
Liraglutide over 18 days reduced total mass (p=0.04), android fat % (p=0.04), and trunk fat (p=0.04) with no lean/bone changes. C-peptide decreased (p=0.026), IGF-1 modestly increased (p=0.002). No MAFI axis changes.
Why it matters
Knowing that fat loss starts quickly and targets the most dangerous fat (abdominal) while sparing muscle provides early reassurance for patients starting GLP-1 therapy.
How the study worked
Randomized double-blind placebo-controlled crossover trial in 20 adults with T2D, 18-day liraglutide (up to 1.8 mg/day) vs placebo with washout, DXA regional body composition, and MAFI hormone panel.
What this study cannot tell us
Very short (18 days). Small sample (n=20). May not predict longer-term composition changes. Crossover design may have carryover effects despite washout.
How to read the evidence
Small but well-designed randomized crossover RCT with DXA body composition. Limited by short duration and sample size.
When this study was published
Published in 2025.
The bigger picture
The selective android fat loss within 18 days suggests GLP-1 drugs preferentially mobilize the metabolically dangerous visceral fat depot first.
Questions still open
- Does the selective android fat loss persist with longer treatment?
- Is the IGF-1 increase a compensatory mechanism protecting lean mass?
- Would these body composition changes differ at higher GLP-1 doses?
Common questions
Does liraglutide burn belly fat specifically?
Will I lose muscle on GLP-1 drugs?
Read the original research
Effects of liraglutide treatment for 18 days on metabolic parameters, regional body composition and the myostatin-activin-follistatin-IGF-1 axis: Results from an exploratory, randomized, placebo-controlled, crossover study.
Diabetes, obesity & metabolism, 28(2), 1258-1265
Citation
Gutierrez de Piñeres, Valeria; Tamayo-Torres, Claudia S; Ramirez-Cisneros, Arantxa; Kavelidou, Marianthi; Stefanakis, Konstantinos; Mantzoros, Christos S. (2026). Effects of liraglutide treatment for 18 days on metabolic parameters, regional body composition and the myostatin-activin-follistatin-IGF-1 axis: Results from an exploratory, randomized, placebo-controlled, crossover study.. Diabetes, obesity & metabolism, 28(2), 1258-1265. https://doi.org/10.1111/dom.70313