Best peptides for weight loss.
This is the one goal where the honest answer is genuinely impressive, and where the gap between the top of the list and everything else is the widest on the site.
Ranked by published evidence · reviewed June 1, 2026
Weight loss is the only outcome in the peptide world where the leading compounds have been tested the way real medicines are tested: randomized, placebo-controlled, tens of thousands of participants, published in major journals, and reviewed by regulators. The incretin drugs at the top of this list are not promising research compounds. They are approved medications with effect sizes large enough that they changed how obesity is treated.
The ranking below follows the same evidence tier used everywhere on this site, which means it sorts by how much human data exists rather than by how large the reported effect is. Those usually agree here, because the compounds with the biggest reported effects are also the ones that have been properly studied. Where they diverge is instructive: a compound in trials with a striking Phase 2 number still ranks below an approved drug with a completed Phase 3 program, because a Phase 2 result is a reason to run Phase 3, not a substitute for it.
Below the approved and in-trial agents, the list drops off sharply. Growth hormone fragments marketed for fat loss trace back to a compound that went through human obesity trials and did not produce clinically meaningful weight loss. A peptide designed to destroy the blood supply of fat tissue showed real weight loss in obese monkeys and also dose-dependent kidney toxicity, and never completed human trials. These are not lesser versions of the drugs above them. They are a different category of thing.
One caveat applies across the whole list and is easy to lose in the excitement about effect sizes. Weight returns for most people after stopping, which means these compounds treat a chronic condition rather than curing it. A meaningful proportion of the weight lost is lean mass, which is true of weight loss by most methods but still matters. And the gastrointestinal side effects that drive the slow dose escalation on every approved label are common rather than rare.
The approved incretin drugs are in a class of their own, supported by the largest obesity trials ever run. Everything marketed as a peptide alternative to them is substantially less proven, and several of the popular options have already failed the trials that would have proven them.
Ranked by evidence.
Ordered by PepCue's evidence tier, not by claimed effect size. A compound with a larger reported result but less human data ranks below one that has actually been tested.
- 01SemaglutideS tier · 95/100FDA-approvedOzempic · Wegovy
Semaglutide is a long-acting glucagon-like peptide-1 (GLP-1) receptor agonist, an acylated, structurally modified analog of the native incretin hormone GLP-1, engineered for once-weekly (injectable) or daily (oral) dosing through albumin binding and resistance to DPP-4 degradation.
Full profile and sources → - 02LiraglutideS tier · 93/100FDA-approvedVictoza · Saxenda
Liraglutide is a long-acting, injectable glucagon-like peptide-1 (GLP-1) receptor agonist, an acylated analog of the human incretin hormone GLP-1.
Full profile and sources → - 03TirzepatideS tier · 92/100FDA-approvedMounjaro · Zepbound
Tirzepatide (development code LY3298176) is a synthetic, 39-amino-acid modified peptide engineered as a "twincretin," a single molecule that activates two incretin hormone receptors at once.
Full profile and sources → - 04TesamorelinA tier · 87/100FDA-approvedEgrifta
Tesamorelin is a synthetic 44-amino-acid analog of human growth hormone-releasing hormone (GHRH/GRF 1-44), stabilized by a trans-3-hexenoic acid group attached to its N-terminus.
Full profile and sources → - 05SurvodutideB tier · 70/100In human trialsBI 456906
Survodutide (BI 456906) is an investigational once-weekly injectable peptide that activates two gut-hormone receptors at once: the glucagon receptor (GCGR) and the glucagon-like peptide-1 receptor (GLP-1R).
Full profile and sources → - 06RetatrutideB tier · 68/100In human trialstriple agonist
Retatrutide (development code LY3437943) is an investigational once-weekly injectable peptide developed by Eli Lilly for the treatment of obesity and related cardiometabolic disease.
Full profile and sources → - 07MazdutideB tier · 68/100In human trialsIBI362 · LY3305677
Mazdutide (IBI362, originally LY3305677) is an investigational once-weekly injectable dual agonist of the GLP-1 and glucagon receptors, based on a mammalian oxyntomodulin analog.
Full profile and sources → - 08CagriSemaC tier · 53/100In human trialscagrilintide + semaglutide
CagriSema is a fixed-combination injectable investigational obesity therapeutic developed by Novo Nordisk that co-formulates two long-acting peptide analogues in a single once-weekly subcutaneous injection: cagrilintide, a long-acting amylin receptor agonist (analogue of the pancreatic hormone amylin), and semaglutide, a GLP-1 (glucagon-like peptide-1) receptor agonist already marketed for diabetes and obesity.
Full profile and sources → - 09CagrilintideC tier · 53/100In human trialsamylin analog
Cagrilintide (development code AM833) is a long-acting, once-weekly synthetic analogue of the pancreatic hormone amylin, developed by Novo Nordisk.
Full profile and sources → - 10AOD-9604D tier · 41/100Research / preclinical
AOD-9604 ("Advanced Obesity Drug 9604") is a synthetic 16-amino-acid peptide corresponding to the C-terminal lipolytic region of human growth hormone (hGH), residues 177–191, with an added tyrosine at the N-terminus.
Full profile and sources → - 11HGH Fragment 176-191F tier · 30/100Research / preclinicalhGH frag 176-191 · GH lipolytic fragment
HGH Fragment 176-191 is a synthetic peptide corresponding to the final 16 amino acids (residues 176 to 191) of the C-terminal region of human growth hormone.
Full profile and sources → - 12AdipotideF tier · 21/100Research / preclinicalFTPP
Adipotide (FTPP, also called prohibitin-targeting peptide-1) is an experimental chimeric peptidomimetic designed to destroy the blood supply of white fat rather than act as a hormone.
Full profile and sources → - 135-Amino-1MQF tier · 15/100Research / preclinical
5-Amino-1MQ (5-amino-1-methylquinolinium) is a small-molecule, substrate-site inhibitor of the enzyme nicotinamide N-methyltransferase (NNMT).
Full profile and sources →
Commonly tried, and why it is not on this list.
HGH and GH secretagogues
Growth hormone changes body composition modestly in specific deficiency states, but GH secretagogues are not weight-loss drugs and have no outcome evidence for that use.
HCG
The FDA label states explicitly that there is no substantial evidence HCG causes weight loss or fat redistribution. The HCG diet is not supported.
FAQ.
Which peptide produces the most weight loss?
In published trials, the triple agonist retatrutide has reported the largest average reductions, followed by tirzepatide among approved drugs. Retatrutide is still investigational and not approved, so the largest reported effect and the best-evidenced option are not currently the same compound.
Are compounded versions the same thing?
No. Compounded semaglutide and tirzepatide are not the FDA-approved products, are not manufactured to the same standard, and in some cases have used different salt forms. The trial evidence attaches to the approved product.
Do these work without diet and exercise?
The trials were generally run alongside lifestyle intervention, and the drugs work primarily by reducing appetite, so eating patterns still determine the result. Resistance training and adequate protein are what the evidence supports for limiting lean-mass loss.
Cite this page
PepCue. “Best peptides for weight loss: ranked by actual evidence.” PepCue, reviewed June 1, 2026. https://www.pepcue.app/best-peptides-for/weight-loss.