Peptide briefs

A small-molecule enzyme blocker (not actually a peptide) marketed alongside peptides as a fat-loss compound; it reduces obesity in mice by inhibiting the enzyme NNMT and raising cellular NAD+, but there is no published human efficacy or safety data at all — so for people, it is a purely preclinical compound being sold as if it were proven.

A small modified fragment of human growth hormone, designed to trigger fat-burning without growth hormone's other effects; it was developed as an obesity drug, showed an early positive signal, but its larger pivotal trial failed to establish meaningful weight loss and development was discontinued — leaving today's 'fat-loss peptide' marketing well ahead of the human evidence.

A synthetic 15-amino-acid peptide, derived from a protein in human gastric juice, that is widely promoted for injury and gut healing but whose evidence is almost entirely from animal studies.

A synthetic growth-hormone-releasing-hormone (GHRH) analog, sold gray-market and usually stacked with ipamorelin; it reliably and durably raises growth hormone and IGF-1 in one human study, but its clinical development was abandoned after a participant death and it has no human evidence for the muscle or anti-aging uses it's sold for.

A synthetic four-amino-acid Russian peptide promoted for longevity and telomere lengthening; it does activate telomerase in cultured human cells and extends lifespan in animals, but the human longevity claims lean on small, non-randomized Russian data — much of it from a related pineal extract, not this peptide — so the 'live longer / reset your telomeres' marketing far outruns the proof.

A naturally occurring copper-binding tripeptide with decades of skin-science research — as a topical cream it has real human data for wrinkle reduction, but the injectable form biohackers use has no controlled human evidence and can't be legally compounded.

A synthetic pentapeptide that selectively triggers short-term growth-hormone release, marketed for muscle growth, fat loss, recovery, and anti-aging — but its only human efficacy trials were for a gut condition (and failed), with no human studies behind the uses it's actually sold for.

A synthetic α-MSH analog, sold gray-market (injection or nasal spray) to tan skin and boost libido — it does measurably do both in small studies, but it is unapproved, unregulated, and linked in case reports to changing moles, melanoma, and acute toxicity.

A peptide your own mitochondria make, which rises with exercise and improves metabolism and insulin sensitivity in animals; it's one of the most scientifically interesting 'exercise mimetic' compounds, but human evidence is still early — strong mouse data and human biomarker studies, with efficacy trials only now beginning — so the fat-loss and anti-aging marketing is ahead of the proof.

An essential cellular coenzyme sold — directly or as the precursors NMN and NR — to slow aging and boost energy; supplements reliably raise NAD+ blood levels, but human trials have mostly not shown the promised health benefits.

A synthetic three-amino-acid 'peptide bioregulator' from one Russian research group, promoted for sleep and brain health — but its evidence is almost entirely animal and cell studies, with no human sleep trial.

A melanocortin receptor agonist that acts on the brain rather than blood flow; it is FDA-approved as Vyleesi for low sexual desire (HSDD) in premenopausal women — where two Phase 3 trials show a real but modest effect — while its heavily marketed off-label use in men and as a general 'libido' shot rests on older, discontinued early-stage data.

An investigational Eli Lilly injectable that activates three gut/metabolic hormone receptors at once and has produced the largest weight loss yet seen in obesity trials — but is not approved or legally available outside clinical trials.

A synthetic Russian anxiolytic peptide derived from the immune molecule tuftsin, used clinically in Russia for anxiety; the human evidence is genuine but thin — a few small, mostly Russian trials, none replicated to Western standards — so its calming and 'nootropic' reputation outruns what's actually been proven.

An FDA-approved GLP-1 medication (Ozempic, Wegovy, Rybelsus) with strong clinical-trial evidence for major weight loss and cardiovascular-risk reduction — but that evidence applies to the prescribed, regulated drug, not to the compounded or 'research-grade' semaglutide widely sold online.

A synthetic Russian neuropeptide based on a fragment of the hormone ACTH, used clinically in Russia for stroke and cognitive disorders; it has real human data and a strong neuroprotective mechanism, but the trials are mostly Russian, small, and often not randomized — so its 'nootropic' and brain-recovery reputation is promising rather than proven.

A growth-hormone-releasing hormone analog that prompts the pituitary to make its own growth hormone; it was once FDA-approved (Geref) for childhood growth-hormone deficiency before being withdrawn for commercial — not safety — reasons, and is now sold compounded and off-label for anti-aging, where the human evidence is real but small.

A mitochondria-targeting peptide that concentrates in the cell's energy machinery and binds cardiolipin; it just became FDA-approved (as Forzinity) for the ultra-rare Barth syndrome, but its large trials in more common conditions — including primary mitochondrial myopathy — largely failed, so the popular 'anti-aging / mitochondrial repair' marketing rests on lab data, not human proof.

A synthetic 7-amino-acid fragment of the natural protein thymosin beta-4, sold for injury recovery — but the real human research is on the full protein, not this fragment.

The FDA-approved GHRH analog (Egrifta) — proven in trials to shrink excess visceral abdominal fat, but only approved for HIV-associated lipodystrophy; its popular off-label use for general fat loss and anti-aging in healthy people is unstudied, and it raises blood sugar.

A 28-amino-acid immune-modulating peptide that's an approved hepatitis-B drug in dozens of countries (as Zadaxin) but not in the US; it has a large, real clinical record — yet its biggest test in sepsis recently failed, and the popular 'immune-boosting / anti-aging' use in healthy people is largely unproven.

An FDA-approved dual GIP/GLP-1 'twincretin' (Mounjaro, Zepbound) that produces the largest weight loss of any approved obesity drug and beat semaglutide head-to-head — but that evidence belongs to the regulated, prescribed drug, not to the compounded or 'research-grade' tirzepatide widely sold online.