Pinc PeptideThe girly peptide research blog

Weight loss · 11 compounds · updated 8 October 2026

Best peptides for weight loss, ranked by the human evidence

11 compounds are sold for weight loss. We rank them by how strong the evidence in people is, not by popularity. 5 of the 11 are FDA-approved for some use; the rest are not.

Three of these peptides are FDA-approved weight-loss medicines: tirzepatide, sold as Zepbound, semaglutide, sold as Wegovy, and liraglutide, sold as Saxenda12345. In head-to-head trials, tirzepatide cut more weight than semaglutide, and weekly semaglutide more than daily liraglutide67. FDA’s shortage list says Saxenda will be available until it is discontinued in January 2027, and generic liraglutide is approved58. Orforglipron, sold as Foundayo, is an FDA-approved daily weight-loss pill, but it is a small drug molecule rather than a peptide; in a 72-week trial in 3,127 adults with obesity but no diabetes, those on the top dose lost 11.2% of their weight, versus 2.1% on placebo910. Tesamorelin is approved only to reduce excess belly fat in adults with HIV and lipodystrophy, an abnormal shift in where the body stores fat, and its label says it is not for weight loss1112.

Retatrutide and CagriSema, which pairs cagrilintide with semaglutide, also produced large weight losses in trials, but as of 30 September 2026, neither retatrutide nor cagrilintide was FDA-approved1314151617. Survodutide and mazdutide each act like two hormones at once, GLP-1 and glucagon1819. In a 76-week trial, adults without diabetes lost 12.2% to 13.0% of their weight on survodutide, versus 5.4% on placebo, but it is not approved anywhere1820. Mazdutide is approved in China, as Xinermei, but not in the US; in a 48-week trial in Chinese adults, weight fell 11.0% to 14.0%, versus a 0.3% gain on placebo192122. AOD-9604 did not beat placebo in its largest trial, of 502 adults, and its developer then dropped it as an obesity drug23. FDA found no published study that gave MOTS-c to people24.

Products sold as “research” semaglutide, tirzepatide or retatrutide are unapproved drugs, which FDA says are of unknown quality and may be harmful17. FDA also says that, under federal law, pharmacies may not use retatrutide or cagrilintide to make their own versions17, and of the latest 200 tests of each by Finnrick, a testing service, 63 retatrutide, 59 tirzepatide and 74 semaglutide samples failed (as of 30 September 2026)252627. People choose which samples to send, so the results are not a random survey2628. Finnrick also listed 13 failures in 27 survodutide tests (April 2025 to April 2026) and 11 in 29 mazdutide tests (April to November 2025)2930.

  1. Tirzepatide

    ABenefit shownApproved (Zepbound, Mounjaro)

    Tirzepatide is a weekly injection for weight loss and type 2 diabetes, sold as Zepbound and Mounjaro12. Trials show large weight loss31, but “research” vials are illegal to sell for human use and often fail tests1726.

    Does it work for weight loss and weight maintenance? In a large trial, people lost 20.9% of their weight on average over 72 weeks on the top dose, versus 3.1% on placebo31. Weight tends to return after stopping32.

  2. Semaglutide

    ABenefit shownApproved (Wegovy, Ozempic, Rybelsus)

    Semaglutide, the drug in Ozempic and Wegovy, cut weight and the risk of heart attack, stroke or heart-related death in large trials3334. Unapproved “research” versions often fail tests27.

    Does it work for long-term weight management? In a large trial, people lost 14.9% of their weight on average over 68 weeks, versus 2.4% on placebo33. A higher 7.2 mg weekly dose cut weight by 18.7%, versus 3.9% on placebo35.

  3. Liraglutide

    ABenefit shownApproved (Saxenda, Victoza, generics)

    Liraglutide is the daily injection in Saxenda and Victoza. In large trials it cut weight, and in type 2 diabetes it lowered the risk of heart attack, stroke or heart-related death3637. In a head-to-head trial, weekly semaglutide cut more weight7.

    Does it work for long-term weight management? In a 56-week trial, adults lost 8.4 kg on average, versus 2.8 kg on placebo36. In a head-to-head trial, weight fell 6.4% on daily liraglutide versus 15.8% on weekly semaglutide7.

  4. Orforglipron

    ABenefit shownApproved (Foundayo)

    Orforglipron (Foundayo) is Eli Lilly’s daily weight-loss pill, FDA-approved in April 20269. It is not a peptide10. On the top dose, adults lost 11.2% of their weight on average over 72 weeks, versus 2.1% on placebo10.

    Does it work for weight loss in adults with obesity or overweight? In a large trial, adults on the top dose lost 11.2% of their weight on average over 72 weeks, versus 2.1% on placebo10. Adults with type 2 diabetes lost less38.

  5. Mazdutide

    ABenefit shownApproved in China as Xinermei; not in the US

    Mazdutide is a weekly weight-loss and diabetes injection, approved in China in 2025, not in the US213940. In a 48-week trial, Chinese adults with excess weight lost 11.0% to 14.0% of body weight, versus a 0.3% gain on placebo22.

    Does it work for weight loss in obesity or overweight? In a 48-week trial in Chinese adults, weight fell 11.0% to 14.0% on average, versus a 0.3% gain on placebo22. It is approved in China, not in the US2139.

  6. Cagrilintide

    ABenefit shownNot approved for any use

    Cagrilintide is an experimental weekly injection from Novo Nordisk that caused large weight loss in trials when paired with semaglutide15. As of 30 September 2026, it is not approved, and vials sold online often fail tests1641.

    Does it work for weight loss, alone or with semaglutide? In a large trial, people taking it with semaglutide lost 20.4% of their weight on average over 68 weeks, versus 3.0% on placebo15. Alone, it worked less well than semaglutide alone42.

  7. Retatrutide

    ABenefit shownNot approved for any use

    Retatrutide is an experimental weekly weight-loss injection from Eli Lilly. Large trials show major weight loss, but it is not approved anywhere, and vials sold online often fail tests132543.

    Does it work for weight loss in obesity or overweight? In a large trial, people without diabetes lost 25% of their weight on average over 80 weeks on the top dose, versus 3.9% on placebo43. It is not approved anywhere13.

  8. Survodutide

    ABenefit shownNot approved for any use

    Survodutide is an experimental weekly weight-loss injection from Boehringer Ingelheim. In a 76-week trial, adults with obesity or overweight and no diabetes lost 12.2% to 13.0% of their weight, versus 5.4% on placebo20. It is not approved anywhere1844.

    Does it work for weight loss in obesity or overweight? Over 76 weeks, adults with obesity or overweight and no diabetes lost 12.2% to 13.0% of their weight on average, versus 5.4% on placebo20. It is not approved anywhere18.

  9. Tesamorelin

    AMixed resultsApproved (Egrifta) for belly fat in HIV only

    Tesamorelin boosts growth hormone and is FDA-approved only for excess belly fat in adults with HIV1112. Other uses have little evidence4546, and vials sold online often fail tests47.

    Does it work for reducing deep belly fat? In two large HIV trials, deep belly fat fell about 15% more than on placebo, then returned after stopping484950. Outside HIV, a 12-month trial lowered it, in people with obesity and low growth hormone output51.

  10. MOTS-c

    DUntestedNot approved for any use

    MOTS-c is a peptide the body makes, coded in the DNA of mitochondria, the cell’s power plants. Injections helped mice resist weight gain and run better, but FDA found no published study that gave it to people245253.

    Does it work for weight loss? FDA found no published study that gave it to people24. In mice, injections cut weight gain on a high-fat diet52.

  11. AOD-9604

    BNo clear benefitNot approved for any use

    AOD-9604 is a lab-made fragment of human growth hormone sold for fat loss. In its developer’s largest trial, of 502 adults, it did not beat placebo for weight loss, and it is not an approved medicine235455.

    Does it work for weight loss in adults with obesity? In its largest trial, 502 adults with obesity took a daily pill or placebo; weight loss was not clearly better on the pill2354. FDA found no human studies of shots under the skin23.

How we ranked them

Compounds that trials show work for this goal come first, then those with mixed results, then those with no controlled human trial for this goal that has public results, and last those that trials found do not work. Within each group, the stronger the human evidence (tier A to E), the higher the place. Ties go to compounds FDA has approved as a medicine, then to those approved only in other countries, then to those whose US approval was withdrawn, then to peptides over non-peptide drugs, then to the winner of a trial that compared the two directly. Popularity, price and how a product is marketed play no part. A high place is not a recommendation to use anything.

Head-to-head trials that set the order here:

  • Tirzepatide above semaglutide. In SURMOUNT-5, a 72-week trial in 751 adults with obesity but no diabetes, weight fell 20.2% on tirzepatide and 13.7% on semaglutide6.
  • Semaglutide above liraglutide. In STEP 8, a 68-week trial in 338 adults with obesity or overweight but no diabetes, weight fell 15.8% on weekly semaglutide and 6.4% on daily liraglutide7.

How we grade evidence →

Head-to-head

Doses used in studies

Further reading

Questions people ask

Do peptides get rid of belly fat?

Some reduce it while people take them: tesamorelin, approved for excess belly fat in adults with HIV, cut deep belly fat about 15% more than placebo over 26 weeks11484950. Semaglutide and tirzepatide, approved for weight loss, shrank waists in trials as overall weight fell13635. In trials, belly fat came back after people stopped tesamorelin, and weight came back after they stopped tirzepatide3248.

What shrinks belly fat the fastest?

In a 72-week trial that compared two approved weight-loss drugs directly, waists shrank by an average of 18.4 cm on tirzepatide and 13.0 cm on semaglutide6. Tesamorelin cut deep belly fat about 15% more than placebo over 26 weeks, but it is approved only for adults with HIV and lipodystrophy, and its label says it does not change body weight1112484950. These trials measured change at set times, such as 26 or 72 weeks, so none of them shows which peptide works fastest650.

What is the best peptide for weight loss?

Tirzepatide, semaglutide and liraglutide all have large trials and FDA approval for weight management1234313336. In trials comparing them directly, weight fell 20.2% on tirzepatide versus 13.7% on semaglutide over 72 weeks, and 15.8% on semaglutide versus 6.4% on daily liraglutide over 68 weeks67. Retatrutide and CagriSema also produced large weight losses in trials, but neither was FDA-approved as of 30 September 20261314151617.

What peptides burn fat?

AOD-9604, a fragment of growth hormone sold for fat loss, did not beat placebo for weight loss in its largest trial, of 502 adults23. MOTS-c cut weight gain in mice on a high-fat diet, but FDA found no published study that gave it to people2452. The approved drugs semaglutide and tirzepatide reduce how much people eat, and their labels say the weight lost is more fat than lean tissue13.

Are weight-loss peptides sold online safe?

Many samples sent for testing fail: of the latest 200 tests of each by Finnrick, a testing service, 63 retatrutide, 59 tirzepatide and 74 semaglutide samples failed (as of 30 September 2026)252627. FDA says “research” versions of these drugs are of unknown quality and may be harmful, and health officials in Victoria, Australia, reported six cases of liver injury in people who used products labeled retatrutide1756. Even the approved medicines have known risks, including an inflamed pancreas and gallbladder disease13. Our guide to compounded GLP-1s covers pharmacy-made semaglutide and tirzepatide.

Sources

  1. 1ZEPBOUND (tirzepatide) injection, for subcutaneous use: prescribing information Eli Lilly and Company via DailyMed (U.S. National Library of Medicine), 28 Aug 2026. dailymed.nlm.nih.gov
  2. 2Drugs@FDA via openFDA: approval history for NDA 215866 (Mounjaro) and NDA 217806 (Zepbound) U.S. Food and Drug Administration (openFDA), accessed 1 Oct 2026. api.fda.gov · data query
  3. 3WEGOVY (semaglutide) injection and tablets: prescribing information (SPL version 19) Novo Nordisk via DailyMed (U.S. National Library of Medicine), 30 Jun 2026. dailymed.nlm.nih.gov
  4. 4SAXENDA (liraglutide) injection: prescribing information (SPL version 22) Novo Nordisk via DailyMed (U.S. National Library of Medicine), 15 Jun 2026. dailymed.nlm.nih.gov
  5. 5Drugs@FDA: applications containing liraglutide (NDA 022341, NDA 206321, BLA 208583 and 11 ANDAs) U.S. Food and Drug Administration (openFDA), 6 Oct 2026. api.fda.gov · data query
  6. 6Tirzepatide as Compared with Semaglutide for the Treatment of Obesity New England Journal of Medicine, 3 Jul 2025. pubmed.ncbi.nlm.nih.gov
  7. 7Effect of Weekly Subcutaneous Semaglutide vs Daily Liraglutide on Body Weight in Adults With Overweight or Obesity Without Diabetes: The STEP 8 Randomized Clinical Trial JAMA, 2022. pubmed.ncbi.nlm.nih.gov
  8. 8FDA Drug Shortages: Liraglutide Injection U.S. Food and Drug Administration, accessed 7 Oct 2026. accessdata.fda.gov
  9. 9Approval letter for NDA 220934, Foundayo (orforglipron) tablets U.S. Food and Drug Administration, 1 Apr 2026. accessdata.fda.gov
  10. 10Orforglipron, an Oral Small-Molecule GLP-1 Receptor Agonist for Obesity Treatment New England Journal of Medicine, 6 Nov 2025. pubmed.ncbi.nlm.nih.gov
  11. 11EGRIFTA SV (tesamorelin) for injection: prescribing information (revised 2/2024) Theratechnologies via DailyMed (U.S. National Library of Medicine), Feb 2024. dailymed.nlm.nih.gov
  12. 12EGRIFTA WR (tesamorelin) for injection: prescribing information (revised 3/2025) Theratechnologies via DailyMed (U.S. National Library of Medicine), Mar 2025. dailymed.nlm.nih.gov
  13. 13Lilly calls on online platforms, payment companies and regulators to shut down the illegal retatrutide black market Eli Lilly and Company (PR Newswire), 12 Aug 2026. prnewswire.com
  14. 14Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity New England Journal of Medicine, 29 Sep 2026. pubmed.ncbi.nlm.nih.gov
  15. 15Coadministered Cagrilintide and Semaglutide in Adults with Overweight or Obesity (REDEFINE 1) New England Journal of Medicine, 14 Aug 2025. pubmed.ncbi.nlm.nih.gov
  16. 16Drugs@FDA via openFDA: search for active ingredient cagrilintide (no matches) U.S. Food and Drug Administration (openFDA), 29 Sep 2026. api.fda.gov · data query
  17. 17FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight Loss U.S. Food and Drug Administration, 1 Oct 2026. fda.gov
  18. 18Boehringer Ingelheim’s survodutide achieves up to 13.1% weight loss in new Phase III trial, alongside significant improvements in glycemic control in people with obesity and type 2 diabetes Boehringer Ingelheim (GlobeNewswire), 1 Oct 2026. globenewswire.com
  19. 19Mazdutide: First Approval Drugs, Dec 2025. pubmed.ncbi.nlm.nih.gov
  20. 20Survodutide Once Weekly for the Treatment of Adults with Obesity New England Journal of Medicine, 20 Aug 2026. pubmed.ncbi.nlm.nih.gov
  21. 21Drugs@FDA via openFDA: search for active ingredient mazdutide (no matches) U.S. Food and Drug Administration (openFDA), 6 Oct 2026. api.fda.gov · data query
  22. 22Once-Weekly Mazdutide in Chinese Adults with Obesity or Overweight New England Journal of Medicine, 12 Jun 2025. pubmed.ncbi.nlm.nih.gov
  23. 23FDA Briefing Document, Pharmacy Compounding Advisory Committee meeting of December 4, 2024: FDA Evaluation of AOD-9604-Related Bulk Drug Substances (AOD-9604 (free base) and AOD-9604 acetate) U.S. Food and Drug Administration, 5 Nov 2024. fda.gov
  24. 24July 23-24, 2026, Meeting of the Pharmacy Compounding Advisory Committee – FDA Briefing Document for MOTS-c-Related Bulk Drug Substances (MOTS-c (free base) and MOTS-c acetate) U.S. Food and Drug Administration, 11 May 2026. fda.gov
  25. 25Retatrutide: vendor test results Finnrick, 29 Sep 2026. finnrick.com
  26. 26Tirzepatide: vendor test results Finnrick, 29 Sep 2026. finnrick.com
  27. 27Semaglutide: public lab test results (Finnrick product page) Finnrick, 29 Sep 2026. finnrick.com
  28. 28We’d Rather Buy the Future Than Wait For It Finnrick, 10 Jun 2026. finnrick.com
  29. 29Survodutide Safety Testing Results & Vendor Ratings Finnrick, accessed 7 Oct 2026. finnrick.com
  30. 30Mazdutide Safety Testing Results & Vendor Ratings Finnrick, accessed 7 Oct 2026. finnrick.com
  31. 31Tirzepatide Once Weekly for the Treatment of Obesity New England Journal of Medicine, 21 Jul 2022. pubmed.ncbi.nlm.nih.gov
  32. 32Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial JAMA, 2 Jan 2024. pubmed.ncbi.nlm.nih.gov
  33. 33Once-Weekly Semaglutide in Adults with Overweight or Obesity New England Journal of Medicine, 2021. pubmed.ncbi.nlm.nih.gov
  34. 34Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes New England Journal of Medicine, 2023. pubmed.ncbi.nlm.nih.gov
  35. 35Once-weekly semaglutide 7.2 mg in adults with obesity (STEP UP): a randomised, controlled, phase 3b trial The Lancet Diabetes & Endocrinology, Nov 2025. pubmed.ncbi.nlm.nih.gov
  36. 36A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management New England Journal of Medicine, 2015. pubmed.ncbi.nlm.nih.gov
  37. 37Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes New England Journal of Medicine, 2016. pubmed.ncbi.nlm.nih.gov
  38. 38Orforglipron, an oral small-molecule GLP-1 receptor agonist, for the treatment of obesity in people with type 2 diabetes (ATTAIN-2): a phase 3, double-blind, randomised, multicentre, placebo-controlled trial The Lancet, 20 Nov 2025. pubmed.ncbi.nlm.nih.gov
  39. 39Voluntary Announcement: First Dual GCG/GLP-1 Receptor Agonist Mazdutide Received Approval by the National Medical Products Administration for Chronic Weight Management Innovent Biologics, Inc. (HKEXnews), 27 Jun 2025. www1.hkexnews.hk
  40. 40Voluntary Announcement: Mazdutide Received Approval from China’s National Medical Products Administration for Glycemic Control in Adults with Type 2 Diabetes Innovent Biologics, Inc. (HKEXnews), 19 Sep 2025. www1.hkexnews.hk
  41. 41Cagrilintide Safety Testing Results & Vendor Ratings Finnrick, accessed 1 Oct 2026. finnrick.com
  42. 42Efficacy of CagriSema for Reaching Anthropometric Treatment Targets and Cardiometabolic Outcomes: A Secondary, Post hoc Analysis of REDEFINE 1 Diabetes, Obesity and Metabolism, Oct 2026. pmc.ncbi.nlm.nih.gov
  43. 43Lilly’s triple agonist, retatrutide, delivered powerful weight loss in pivotal Phase 3 obesity trial Eli Lilly and Company (PR Newswire), 21 May 2026. prnewswire.com
  44. 44Survodutide Phase 3 Data Signal Metabolic Gains Beyond Weight Loss AJMC (The American Journal of Managed Care), 8 Jun 2026. ajmc.com
  45. 45Effects of growth hormone-releasing hormone on cognitive function in adults with mild cognitive impairment and healthy older adults: results of a controlled trial Archives of Neurology, Nov 2012. pubmed.ncbi.nlm.nih.gov
  46. 46Effects of a growth hormone-releasing hormone analog on endogenous GH pulsatility and insulin sensitivity in healthy men The Journal of Clinical Endocrinology & Metabolism, Jan 2011. pubmed.ncbi.nlm.nih.gov
  47. 47Tesamorelin: safety testing results and vendor ratings Finnrick, 24 Sep 2026. finnrick.com
  48. 48Effects of tesamorelin, a growth hormone-releasing factor, in HIV-infected patients with abdominal fat accumulation: a randomized placebo-controlled trial with a safety extension Journal of Acquired Immune Deficiency Syndromes, Mar 2010. pubmed.ncbi.nlm.nih.gov
  49. 49Effects of tesamorelin (TH9507), a growth hormone-releasing factor analog, in human immunodeficiency virus-infected patients with excess abdominal fat: a pooled analysis of two multicenter, double-blind placebo-controlled phase 3 trials with safety extension data The Journal of Clinical Endocrinology & Metabolism, Sep 2010. pubmed.ncbi.nlm.nih.gov
  50. 50Metabolic effects of a growth hormone-releasing factor in patients with HIV New England Journal of Medicine, 6 Dec 2007. pubmed.ncbi.nlm.nih.gov
  51. 51Metabolic effects of a growth hormone-releasing factor in obese subjects with reduced growth hormone secretion: a randomized controlled trial The Journal of Clinical Endocrinology & Metabolism, Dec 2012. pubmed.ncbi.nlm.nih.gov
  52. 52The mitochondrial-derived peptide MOTS-c promotes metabolic homeostasis and reduces obesity and insulin resistance Cell Metabolism, 3 Mar 2015. pubmed.ncbi.nlm.nih.gov
  53. 53MOTS-c is an exercise-induced mitochondrial-encoded regulator of age-dependent physical decline and muscle homeostasis Nature Communications, 20 Jan 2021. pubmed.ncbi.nlm.nih.gov
  54. 54Safety and Tolerability of the Hexadecapeptide AOD9604 in Humans Journal of Endocrinology and Metabolism, Apr 2013. jofem.org
  55. 55The emerging landscape of performance-enhancing peptides modulating GH-IGF1 axis: bridging the gap between clinical evidence and patient self-administration Frontiers in Endocrinology, 2026. pubmed.ncbi.nlm.nih.gov
  56. 56Toxicity linked to unapproved peptide product labelled Retatrutide Department of Health, Victoria, 19 Jun 2026. health.vic.gov.au

Not medical advice. Each compound page cites its sources for every claim above. All compounds in one table · Report an error.