FAQ
Frequently Asked Questions
Direct answers to the questions readers most often bring to this desk, cited back to the source.
What does a GHK-Cu peptide do?
GHK-Cu is a copper-binding tripeptide best studied as a topical cosmetic ingredient. It stimulates dermal fibroblasts to make more collagen, elastin and other matrix proteins, and the copper it carries supports enzymes involved in cross-linking and antioxidant activity [6][7]. In reviewed studies, topical GHK-Cu increased procollagen synthesis in about 70% of treated subjects, compared with 50% for vitamin C and 40% for retinoic acid [1][4]. It has no approved indication for injection or systemic use.
What is GHK-Cu and how does it work?
GHK-Cu is glycyl-L-histidyl-L-lysine bound to a copper(II) ion, occurring naturally within human collagen. It works by acting on dermal fibroblasts, keratinocytes and other cell types at extremely low concentrations, shifting gene expression toward tissue-repair, antioxidant and protein-quality-control programs — an effect measured across roughly 31.2% of human genes at a 50%-or-greater change threshold in gene-expression analysis [2].
Is GHK-Cu peptide really anti-aging?
The controlled human evidence supports specific, measured skin effects — increased procollagen synthesis and, in a related combination formulation, a significant hair-count increase over placebo [1][3][4] — rather than a general "anti-aging" claim. Most of the broader anti-aging narrative around GHK-Cu extrapolates from cell, rodent and gene-database work, much of it from a single research group, beyond what the small human topical trials directly demonstrate [1][4]. This site reports the measured findings and flags where the marketing outruns them.
What is the difference between GHK and GHK-Cu?
GHK is the bare three-amino-acid peptide; GHK-Cu is that same peptide bound to a copper ion. The copper coordination is not incidental — laboratory studies indicate that plain GHK without bound copper does not reproduce key documented effects, such as stimulation of certain matrix-remodeling enzymes, in cell studies. Most of the literature summarized on this hub is specific to the copper-bound complex, and the form used in a given study matters when comparing claims.
What is ipamorelin?
Ipamorelin is a synthetic five-amino-acid peptide that selectively triggers growth hormone release by activating the ghrelin receptor (GHS-R1a) on pituitary cells. Its defining pharmacological feature is that it does this without meaningfully raising cortisol or prolactin, distinguishing it from older secretagogues [11]. It has never been approved as a drug and has one published human efficacy trial, which did not meet its primary endpoint [10].
What does ipamorelin do for you?
In its founding pharmacology, ipamorelin triggers a discrete pulse of growth hormone release, peaking about 40 minutes after dosing in a small human pharmacokinetic study [11]. Beyond that acute GH pulse, the only controlled human efficacy trial — testing whether it sped recovery after bowel surgery — found no statistically significant benefit over placebo [10]. Reported sleep, recovery and body-composition effects circulating in research communities are anecdotal, not clinical evidence, and are not established by any published human trial.
What is ipamorelin peptide?
Ipamorelin is a pentapeptide with the sequence Aib-His-D-2-Nal-D-Phe-Lys-NH2, derived from an earlier compound (GHRP-1) by removing a central segment. It is sold as a research chemical and is not FDA-approved for any human use; in 2024 the FDA also removed ipamorelin acetate from the interim list of substances a compounding pharmacy may legally use.
What are the risks of ipamorelin?
The documented risks are mostly mechanistic rather than directly observed in ipamorelin-specific human data: growth-hormone-axis stimulation carries a class-level, theoretical cancer caution tied to IGF-1's role as a growth signal, and a related receptor-class compound produced heart-tissue damage in a 28-day rat study, a class-level signal rather than an ipamorelin-specific finding [9]. No long-term human safety study of ipamorelin exists at any dose, and research-grade material from unregulated suppliers carries no pharmaceutical purity assurance.
What is tesamorelin?
Tesamorelin is a synthetic 44-amino-acid analogue of human growth-hormone-releasing hormone (GHRH), modified to resist rapid enzymatic breakdown. It is the only compound on this hub with an FDA approval — since 2010, to reduce excess abdominal fat in people with HIV-associated lipodystrophy [15].
What does tesamorelin do?
Tesamorelin stimulates the body's own pulsatile release of growth hormone, which in turn raises IGF-1 and promotes fat breakdown with a preference for visceral fat. A 2026 meta-analysis of five pooled randomized trials found it reduced visceral fat by roughly 27.7 square centimeters and liver fat by about 4.3 percentage points on average, without a significant increase in serious adverse events [13].
How does tesamorelin work?
It binds the GHRH receptor on pituitary somatotroph cells, activating a signaling cascade that increases growth hormone synthesis and release. The resulting GH drives hepatic IGF-1 production, and GH and IGF-1 together promote lipolysis, preferentially in visceral fat depots [16]. Because it amplifies an existing physiological rhythm rather than supplying growth hormone directly, its metabolic profile differs somewhat from recombinant growth hormone therapy.
Will tesamorelin help me lose belly fat?
Tesamorelin's approval and its strongest trial evidence are specific to visceral-fat reduction in people with HIV-associated lipodystrophy, a defined medical condition [13][15][17]. Trial data in that population show a real, statistically significant visceral-fat reduction, but the effect was not shown to be permanent — a 52-week program found fat reaccumulated once treatment stopped [17]. This site does not make a general fat-loss recommendation outside the population and indication the trials actually studied, and describes no dosing for any use.