GLP-1 Evidence

Evidence map

Muscle loss: what the evidence base looks like

8 publications, 5 of them trials and 2 syntheses. This page describes the shape of that literature rather than summarising its conclusions.

Updated 3 min read 8 citations

What the evidence on muscle loss is made of Of 8 publications on this topic, the breakdown by study type: 2 meta-analysis, 5 randomised trial, 1 review. 251meta-analysis (2)randomised trial (5)review (1)
8 publications, by study type. Volume is not strength — the same count can be a settled question or a pile of commentary, and which one it is depends almost entirely on this breakdown. Harvested from PubMed and Crossref; publication type as recorded by the source.

What this literature is made of

There is a real trial literature here, but comparatively little synthesis. Individual trials can disagree, and without meta-analysis it is easy to find one that supports almost any position.

The distinction that matters most is between synthesis and primary research. A meta-analysis pools trials and is the closest thing to a settled answer a field produces. A narrative review is one group's reading of the same material and can be selective without being dishonest. Counting them together, which most citation counts do, obscures exactly the thing you want to know.

When the muscle loss literature was published Publication years for the 8 papers on this topic, grouped into bands from before 2015 through to 2023 onwards. 2023 onwards5 papers2020-20222 papers2015-20191 papers
Still active. The most recent paper here is from 2026, so this is a field where an answer written today may not hold for long. Publication years as recorded by PubMed and Crossref.

How this page is built

Everything above is computed from the citations this site harvested from PubMed and Crossref, not written by hand. When the weekly harvest finds a new paper on this topic, these counts change and the characterisation changes with them. That is the point: a hand-written claim about how strong an evidence base is starts decaying the day it is written.

Publication type is taken as the source records it. That is imperfect — journals label inconsistently, and a paper indexed as a "review" may be a systematic one — so treat the bands as approximate. They are accurate enough to distinguish a trial literature from a commentary literature, which is the distinction that matters.

The strongest work on this topic

Ordered by study design first, then recency. The full set is listed in the references below.

  1. Effect of glucagon-like peptide-1 receptor agonists and co-agonists on body composition: Systematic review and network meta-analysis — Karakasis P, Patoulias D, Fragakis N et al., 2025, meta-analysis
  2. A systematic review of the effect of semaglutide on lean mass: insights from clinical trials — Bikou A, Dermiki-Gkana F, Penteris M et al., 2024, systematic review
  3. Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study of adults with obesity or overweight — Look M, Dunn JP, Kushner RF et al., 2025, randomised controlled trial
  4. Tirzepatide Reduces Appetite, Energy Intake, and Fat Mass in People With Type 2 Diabetes — Heise T, DeVries JH, Urva S et al., 2023, randomised controlled trial
  5. Semaglutide once a week in adults with overweight or obesity, with or without type 2 diabetes in an east Asian population (STEP 6): a randomised, double-blind, double-dummy, placebo-controlled, phase 3a trial00008-0) — Kadowaki T, Isendahl J, Khalid U et al., 2022, randomised controlled trial
  6. Once-Weekly Semaglutide in Adults with Overweight or Obesity — Wilding JPH, Batterham RL, Calanna S et al., 2021, randomised controlled trial
  7. Effects of once-weekly semaglutide on appetite, energy intake, control of eating, food preference and body weight in subjects with obesity — Blundell J, Finlayson G, Axelsen M et al., 2017, randomised controlled trial
  8. Semaglutide therapy for metabolic dysfunction-associated steatohepatitis: November 2025 updates to AASLD Practice Guidance — Bansal MB, Patton H, Morgan TR et al., 2026, review
How much research is there on muscle loss?
8 publications are indexed here, of which 5 are trials and 2 are syntheses.
Does more research mean a stronger conclusion?
No. Composition matters more than volume — five randomised trials support a claim far better than fifty commentaries, and citation counts do not distinguish between them.
How current is this?
The most recent paper indexed here is from 2026. The set is refreshed weekly from PubMed and Crossref.
Why does this page not tell me the answer?
Because summarising a literature into a conclusion requires reading it, and doing that automatically is how confident nonsense gets published. This page tells you how much weight a conclusion could bear; the articles on this site do the interpreting.

References

Every citation below links to the original peer-reviewed record on PubMed or via DOI. Nothing here is a substitute for medical advice.

  1. Effect of glucagon-like peptide-1 receptor agonists and co-agonists on body composition: Systematic review and network meta-analysis Karakasis P, Patoulias D, Fragakis N, et al. · Metabolism: clinical and experimental · 2025 · Meta-analysis DOIPubMed 39719170
  2. A systematic review of the effect of semaglutide on lean mass: insights from clinical trials Bikou A, Dermiki-Gkana F, Penteris M, et al. · Expert opinion on pharmacotherapy · 2024 · Systematic review DOIPubMed 38629387
  3. Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study of adults with obesity or overweight Look M, Dunn JP, Kushner RF, et al. · Diabetes, obesity & metabolism · 2025 · Randomised controlled trial DOIPubMed 39996356Full text
  4. Tirzepatide Reduces Appetite, Energy Intake, and Fat Mass in People With Type 2 Diabetes Heise T, DeVries JH, Urva S, et al. · Diabetes care · 2023 · Randomised controlled trial DOIPubMed 36857477Full text
  5. Semaglutide once a week in adults with overweight or obesity, with or without type 2 diabetes in an east Asian population (STEP 6): a randomised, double-blind, double-dummy, placebo-controlled, phase 3a trial Kadowaki T, Isendahl J, Khalid U, et al. · The lancet. Diabetes & endocrinology · 2022 · Randomised controlled trial DOIPubMed 35131037
  6. Once-Weekly Semaglutide in Adults with Overweight or Obesity Wilding JPH, Batterham RL, Calanna S, et al. · The New England journal of medicine · 2021 · Randomised controlled trial DOIPubMed 33567185
  7. Effects of once-weekly semaglutide on appetite, energy intake, control of eating, food preference and body weight in subjects with obesity Blundell J, Finlayson G, Axelsen M, et al. · Diabetes, obesity & metabolism · 2017 · Randomised controlled trial DOIPubMed 28266779Full text
  8. Semaglutide therapy for metabolic dysfunction-associated steatohepatitis: November 2025 updates to AASLD Practice Guidance Bansal MB, Patton H, Morgan TR, et al. · Hepatology (Baltimore, Md.) · 2026 · Review DOIPubMed 41201884