Weight, blood sugar & heart
Peptides for weight loss
Sixteen peptides, and the widest spread on the site.
The evidence mix
The 16 peptides on this page, by how well they have been tested.
- Approved medicine9 peptides
- Still being tested in people5 peptides
- Tested in people, but barely1 peptide
- Only tested on animals1 peptide
- No real evidence at allnone on this page
Three approved medicines are licensed for weight loss itself and carry published phase 3 data covering tens of thousands of people. A fourth is licensed for weight loss too, but only in a few rare genetic conditions, and its own pivotal trial did not separate from a dummy injection across everyone it randomised — it is not a competitor to the first three. Five more are approved medicines not approved for weight loss at all: two are for diabetes, one for a specific fat problem in HIV, one is growth hormone, where pooled trials in healthy older adults moved fat and lean tissue without moving the number on the scale, and one has carried a regulator-ordered statement that it is not effective for obesity since the 1970s and is sold for it anyway. Five compounds are in late-stage testing, one of them already approved in China. The last two are sold on the gray market: one failed the trial that was meant to prove it, the other has never been measured in a person at all. The distance between the first entry on this page and the last is the whole scale.
All 16 peptides on this page
Strongest evidence first.
Approved medicine
Approved by the European or US medicines regulator for a named condition, after large randomised trials, with a public product information sheet anyone can read.
9 peptides
- Evidence level 5 of 5: Approved medicine
Dulaglutide
Trulicity · LY2189265
Approved for type 2 diabetes, and in the US also for reducing heart attacks and strokes in people who already have it — but not approved anywhere for weight loss.
Ten randomised trials and a 9,901-person heart trial support the diabetes and heart claims; the weight it takes off is real but small, about 3.2 kg against 1.5 kg on dummy injections.
Sold as: Metabolic
- Evidence level 5 of 5: Approved medicine
Exenatide
Byetta · Bydureon
Approved for type 2 diabetes since 2005, and the first medicine of its kind anywhere — a synthetic copy of a lizard peptide, not a human hormone.
Placebo-controlled trials show lower blood sugar and one to two kilograms of weight loss, but the 14,752-person heart trial missed its target and newer weekly injections beat it in head-to-head trials.
Sold as: Metabolic
- Evidence level 5 of 5: Approved medicine
hCG (human chorionic gonadotropin)
human chorionic gonadotropin · human chorionic gonadotrophin
Approved for fertility treatment and for low testosterone in men, and promoted separately for weight loss and for restarting testosterone after steroids.
The approved uses rest on regulator-grade evidence; for weight loss it did not beat a dummy injection, and the US label has said so since 1974.
Sold as: Therapeutic
- Evidence level 5 of 5: Approved medicine
Liraglutide
Saxenda · Victoza
Approved for type 2 diabetes and weight management.
Large controlled trials show lower blood sugar and weight loss compared with placebo.
Sold as: Metabolic
- Evidence level 5 of 5: Approved medicine
Semaglutide
Ozempic · Wegovy
Approved for type 2 diabetes and weight management.
Large controlled trials show lower blood sugar, substantial weight loss and fewer cardiovascular events in specific groups.
Sold as: Metabolic
- Evidence level 5 of 5: Approved medicine
Setmelanotide
Imcivree · IMCIVREE (setmelanotide)
Approved for obesity caused by hypothalamic damage, Bardet-Biedl syndrome or three named gene faults — not for ordinary obesity.
One randomised trial found BMI fell about 16 per cent against a 3 per cent rise on a dummy injection; the trials in the genetic conditions had 10 to 44 people and mostly no comparison group.
Sold as: Therapeutic
- Evidence level 5 of 5: Approved medicine
Somatropin
Recombinant human growth hormone · rhGH
Approved for growth failure in children and growth hormone deficiency in adults, and promoted far beyond that for anti-ageing, fat loss and muscle.
Randomised trials support the approved uses; in healthy adults it shifted fat and lean tissue without improving strength, endurance or function.
Sold as: Therapeutic
- Evidence level 5 of 5: Approved medicine
Tesamorelin
Egrifta · Egrifta SV
Approved in the United States to shrink the deep belly fat of adults with HIV-related lipodystrophy, and promoted elsewhere for fat loss, muscle and anti-ageing.
Two large placebo-controlled trials measured the fat reduction; Europe's regulator judged the same data did not show any health benefit and never approved it.
Sold as: Therapeutic
- Evidence level 5 of 5: Approved medicine
Tirzepatide
Mounjaro · Zepbound
Approved for type 2 diabetes and weight management.
Large controlled trials show lower blood sugar and substantial weight loss compared with placebo and other treatments.
Sold as: Metabolic
Still being tested in people
Currently in registered clinical trials in humans, but not approved anywhere yet. The trials may still fail — most drugs at this stage do.
5 peptides
- Evidence level 4 of 5: Still being tested in people
Cagrilintide
AM833 · CagriSema (combined with semaglutide)
Being studied for weight loss, mainly in combination with semaglutide.
Large late-stage trials exist for the combination, but cagrilintide on its own is not an approved medicine.
Sold as: Metabolic
- Evidence level 4 of 5: Still being tested in people
Mazdutide
IBI362 · LY3305677
Approved in China for weight loss and type 2 diabetes, and experimental everywhere else.
Four published phase 3 trials show large weight loss and lower blood sugar against dummy injections, all of them run in China.
Sold as: Metabolic
- Evidence level 4 of 5: Still being tested in people
Pemvidutide
ALT-801 · Altimmune ALT-801
Being studied for weight loss and for fatty liver disease; not approved anywhere.
The liver trial cleared inflammation against dummy injections but missed its second target, the scarring, and the 48-week weight-loss results have never been published in a journal.
Sold as: Metabolic
- Evidence level 4 of 5: Still being tested in people
Retatrutide
LY3437943
Being studied for weight loss and type 2 diabetes.
Human trials show large weight changes, but it remains experimental and is not approved.
Sold as: Metabolic
- Evidence level 4 of 5: Still being tested in people
Survodutide
BI 456906
Being studied for weight loss and fatty liver disease.
Large human trials have measured changes in weight and liver disease, but it is not an approved medicine.
Sold as: Metabolic
Tested in people, but barely
Human studies exist, but they are small, short, uncontrolled, paid for by the seller, or they measure something easy to measure instead of something that matters.
1 peptide
Only tested on animals
The evidence is animal experiments, cells in a dish, or computer models. No meaningful controlled trial in humans has been published.
1 peptide