Treatments and supplements · Semaglutide (Ozempic, Wegovy)

Does semaglutide actually work for losing weight?

What we can tell you today: how thoroughly this has been studied.

Thoroughly studied

11 studies, of which 7 bring together the results of several trials in people. This is as strong as evidence gets.

5 Repeated evidence 7 studies

4 Large controlled trial 4 studies

This says how thoroughly something has been studied — not whether it works for you. What each study actually found is in the study itself, and in the plain-language write-ups we are adding.

Appears under: Weight loss and GLP-1

The studies

4 Large controlled trial Once-Weekly Semaglutide in Adults with Overweight or Obesity.
2021 · The New England journal of medicine · 1,961 participants
5 Repeated evidence A systematic review of the effect of semaglutide on lean mass: insights from clinical trials.
2024 · Expert opinion on pharmacotherapy
5 Repeated evidence Potent incretin-based therapy for obesity: A systematic review and meta-analysis of the efficacy of semaglutide and tirzepatide on body weight and waist circumference, and safety.
2024 · Obesity reviews : an official journal of the Internatio · 5,140 participants
5 Repeated evidence Once-Weekly Semaglutide Versus Once-Daily Liraglutide for Weight Loss in Adults: A Meta-Analysis of Randomized Controlled Trials.
2025 · Clinical and translational science · 922 participants
5 Repeated evidence Who Wins the Battle Against Obesity? A Network Meta-Analysis Comparing Tirzepatide and Semaglutide.
2026 · Journal of diabetes · 367 participants
5 Repeated evidence Efficacy and Safety of Cagrilintide and Cagrisema Versus Semaglutide as Anti-Obesity Medications: A Systematic Review, Meta-Analysis and Meta-Regression.
2026 · Diabetes, obesity & metabolism · 3,545 participants
4 Large controlled trial Psychiatric Safety of Semaglutide for Weight Management in People Without Known Major Psychopathology: Post Hoc Analysis of the STEP 1, 2, 3, and 5 Trials.
2024 · JAMA internal medicine · 3,377 participants
5 Repeated evidence Effectiveness & safety of semaglutide in weight reduction in obese nondiabetic patients: A systematic review and meta-analysis.
2026 · Medicine · 3,613 participants
5 Repeated evidence A Systematic Review and Meta-Analysis of Semaglutide Effects on Adipose Tissue and Emerging Effects on Brain and Cognition.
2026 · Obesity reviews : an official journal of the Internatio · 23 participants
4 Large controlled trial Tirzepatide compared with semaglutide in obesity disease: a subpopulation analysis applying Japan Society for the Study of Obesity criteria in the global SURMOUNT-5 trial.
2026 · Current medical research and opinion · 750 participants
4 Large controlled trial Semaglutide Injection Once-Weekly for Weight Management in Adults: Results From A Randomized Phase III, Active-Controlled Study.
2026 · Diabetes, obesity & metabolism · 270 participants · manufacturer helped fund this