What did @meghanmctavish actually say?
Meghan claims she has been injecting GHK-Cu into her gluteal muscle for ten weeks and attributes noticeably plumper, more even, "juicier" skin to the peptide. She describes GHK-Cu as "a naturally occurring amino acid that your body has" and says that injecting it is like "shoving it back in and topping yourself up." She also pivots to plug NAD injections for PMDD-related brain fog, and discloses she is affiliated with the Australian supplier she recommends.
A few things to note right away: GHK-Cu is not an amino acid. It is a tripeptide-copper complex, meaning it is made of three amino acids bound to a copper ion. That is not a trivial distinction. She also switches mid-video between two separate compounds, two separate symptom claims, and a commercial referral code, which makes this video doing a lot of work at once.
Does the science back this up?
Partially, yes, but the evidence is mostly preclinical or in vitro, and what human data exists is largely topical, not injectable. The leap from "promising in a petri dish" to "inject this in your butt for glowing skin" is not one the published literature has made.
GHK-Cu does have a reasonably interesting research profile. In vitro studies show it can stimulate collagen synthesis, activate antioxidant pathways, and influence gene expression related to skin repair. A 2009 review by Pickart and Margolina in the journal Archives of Dermatological Research documented these effects thoroughly. A 2018 paper by Pickart, Vasquez-Soltero, and Margolina in Biomolecules extended those findings, showing GHK-Cu upregulates genes associated with skin remodeling. However, these are not clinical trials of injectable GHK-Cu in humans. Most human studies involve topical formulations, and even those are small and industry-adjacent. There is no published randomized controlled trial of subcutaneous or intramuscular GHK-Cu injection for cosmetic skin outcomes in healthy adults.
What did they get wrong (or right)?
Wrong: calling GHK-Cu an amino acid. It is a copper-binding tripeptide. This matters because it changes how the molecule behaves, how it is absorbed, and how it should be discussed in a medical context. Getting the basic biochemistry wrong while promoting injectable use is a problem.
Also wrong: the framing that injecting GHK-Cu is simply "topping yourself up." Endogenous GHK-Cu levels do decline with age, but the assumption that supplementing exogenous peptide via injection replicates or restores that signaling system in a predictable way is not established. Pharmacokinetics of injected GHK-Cu in humans are not well characterized in the published literature.
Partially right: GHK-Cu is indeed associated with skin-relevant biological activity. The collagen and elastin synthesis signals are documented. And it is honest that she discloses personal use and a commercial relationship. That disclosure is more than most peptide influencers bother with.
The NAD claim for PMDD brain fog is essentially unverifiable from available evidence. NAD precursor research in neurological contexts is early-stage, and "covering post-brain fog" from PMDD is not a studied indication for injectable NAD.
What should you actually know?
If you are curious about GHK-Cu, the honest answer is: the biology is interesting, the human evidence is thin, and injecting an unregulated peptide sourced from an overseas supplier carries real risks that this video does not address. Injectable peptides sold outside a licensed pharmacy or compounding facility are not subject to sterility testing, purity verification, or dose standardization. That is not a hypothetical concern. The FDA and TGA have both flagged risks from unregulated injectable peptides, including contamination and incorrect concentration.
Cosmetic outcomes after eight to ten weeks of any new routine are also notoriously hard to attribute. Sleep, hydration, stress reduction, placebo effect, and lighting all influence how skin looks and feels. Without a controlled comparison, "my skin feels juicier" is a personal observation, not evidence.
If you want to explore GHK-Cu, a conversation with a licensed dermatologist or compounding-pharmacy-affiliated physician is the appropriate starting point, not a TikTok affiliate code. The peptide may have a future in regulated aesthetic medicine. It is not there yet.