Best Peptides for Fat Loss & Body Recomposition

AOD-9604 is a synthetic fragment of human growth hormone: residues 177 to 191 of the hormone with an extra tyrosine added at the front, 16 amino acids in total. The idea was to keep the fat-burning end of growth hormone while leaving out the part that raises IGF-1 or messes with blood sugar. It was developed by Metabolic Pharmaceuticals in Australia and tested as an anti-obesity drug, but it is not approved by the FDA or any major regulator, development stopped after its big Phase IIb trial missed its weight-loss target, and it is banned in sport by WADA.

SLU-PP-332 is a small synthetic molecule, not a peptide, that turns on the estrogen-related receptors (ERRalpha, beta and gamma), the master switches behind much of the body's response to endurance exercise. Researchers call it an 'exercise mimetic' because in mice it boosts mitochondria, shifts muscle toward fatigue-resistant fibers, improves stamina and trims fat without the animal moving more. It was made as a lab tool to study exercise biology. There are no human trials.

Adipotide is an experimental peptide built to kill fat tissue by cutting off its blood supply. One half homes in on prohibitin, a protein on the blood vessels that feed white fat, and the other half is a cell-killing sequence that triggers those vessel cells to self-destruct. It produced striking weight loss in obese mice and monkeys, but it also caused kidney damage in every primate species tested, and its only human trial was terminated after enrolling 4 people with no results ever posted.

HGH Fragment 176-191 is exactly what it sounds like: a short tail-end piece of the human growth hormone molecule, amino acids 176 through 191. The idea was to keep the fat-burning part of growth hormone while ditching the parts that raise blood sugar and IGF-1. The bare fragment has never been tested in a controlled human trial. Its modified cousin, AOD-9604, did go through real obesity trials, and the blunt result is that it was very safe but did not produce meaningful weight loss. It is banned in sport by WADA.

First, a correction worth making loudly: 5-amino-1MQ is not a peptide. It is a small molecule (5-amino-1-methylquinolinium), and it gets lumped in with research peptides mostly because of the crowd that sells it. It blocks an enzyme called NNMT, and in obese mice it produced weight and fat loss without the animals eating less. No human trials have been published.

Retatrutide is the heavy hitter of the new weight-loss drugs: a once-weekly injectable peptide that hits three receptors at once - GIP, GLP-1, and glucagon - earning it the nickname triple-G agonist. In phase 2 it produced about 24 percent weight loss at the top dose, and in the phase 3 TRIUMPH-1 trial Lilly reported 28.3 percent at 12 mg over 80 weeks. It is investigational, made by Eli Lilly, and not FDA approved; Lilly plans to file with the FDA in the first quarter of 2027. Because it is not an approved drug, FDA says it cannot be legally compounded.

Survodutide is an injectable dual agonist that hits both the GLP-1 and glucagon receptors, discovered by Zealand Pharma and developed by Boehringer Ingelheim. It is being tested for obesity and for fatty liver disease (MASH), and it carries an FDA Breakthrough Therapy designation for MASH. It is still investigational and not approved for any use as of October 2026, and no US filing has been publicly announced.

Mazdutide is a GLP-1 and glucagon dual agonist, which puts it between semaglutide (GLP-1 only) and retatrutide (GLP-1, GIP and glucagon). It is built on oxyntomodulin, a natural gut hormone that hits both receptors, rather than on a GLP-1 backbone. It is furthest along in China, where it is approved for both weight management and type 2 diabetes. Western approval has not happened.

CJC-1295 is a synthetic analog of growth hormone-releasing hormone (GHRH), specifically a modified GHRH(1-29). The name covers two different products. CJC-1295 with DAC (Drug Affinity Complex) binds blood albumin, which stretches its half-life to roughly 6 to 8 days and raises GH and IGF-I for days from a single injection; this is the version ConjuChem took to Phase II before abandoning it, and the version the human data are about. CJC-1295 without DAC (Modified GRF 1-29, the form this page is named for) lacks the albumin tether and is much shorter acting, though its human half-life has not been formally published. Neither is an approved drug, both are sold only as research chemicals, and GHRH analogs are banned in sport by WADA.

AICAR is not a peptide at all. It is a small nucleoside (a building block related to the purine pathway) that cells convert into ZMP, a molecule that mimics AMP and switches on AMPK, the cell's energy sensor. It became famous in 2008 when a Salk Institute study showed sedentary mice on AICAR ran 44% further, earning it the "exercise in a pill" label. Human data tell a much less exciting story: it was tested as an intravenous drug (acadesine) for heart surgery and leukemia, the big heart trial failed, and nothing is approved.

MOTS-c is a 16-amino-acid peptide your own mitochondria make, encoded inside the 12S rRNA region of mitochondrial DNA and discovered in 2015. It is studied as a metabolic regulator and a so-called exercise mimetic, because its levels rise when you work out and it improves insulin sensitivity in animals. The catch: the impressive results are almost entirely in mice, with no completed published human efficacy trials.