Copper peptides have become the darling of social media skin care hacks. People are smearing the electric-blue tincture on their face or drawing the concoction up in syringes.
The compound, known as GHK-Copper, or simply GHK-Cu, has gained a massive following because of claims it can deliver firm and wrinkle-free skin, better hair and other anti-aging benefits.
The interest, in part, reflects the broader peptide-craze that has increasingly entered the mainstream wellness and longevity space.
As with many of these trendy peptides, GHK-Cu isn't an approved drug, but it does have considerable scientific research behind it. Topical copper peptide serums and creams have been on the market for decades and studied in human trials.
What has changed recently is how people are administering this peptide: Instead of slathering it on their face, many are opting to take it as a subcutaneous injection. Sometimes it's "stacked" with other peptides that are promoted for tissue repair and anti-aging.
There is no data from published human studies to show this practice is safe and effective. And the risks are compounded by the fact that many people are sourcing the injectable formulations from a grey market of online sellers.
"I think GHK can have a major role in helping enhance longevity," says Dr. Warren Ladiges, a professor at the University of Washington School of Medicine who has been involved in studying the peptide for many years.
"But injecting yourself without really knowing what it's going to do? I wouldn't do that to myself," he adds.
Despite the recent surge in popularity, the peptide has a history that stretches back more than fifty years.
The focus on skin health
In the early 1970s, a chemist named Loren Pickart first isolated GHK – a string of three amino acids Glycyl-L-histidyl-L-lysine – after noticing that bathing liver cells in the lab with plasma from younger adults helped revive them.
By collecting blood from medical students and comparing it to their older professors, he also established that levels decline as people age.
Since then, studies have found that GHK-Cu stimulates collagen production and other compounds involved in skin remodeling, triggers the growth of new blood vessels and has anti-inflammatory effects.
The controlled studies in humans have focused almost exclusively on skin health and aesthetics, and to a lesser extent on wound healing and hair growth.
These are generally small trials funded by the cosmetic industry showing GHK-Cu as a serum or cream improves thickness and elasticity, decreases wrinkles, promotes hair growth and delivers other benefits for damaged skin.
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"The science behind this is very solid," says Dr. David Goldberg, director of cosmetic dermatology for the Schweiger Dermatology Group and a clinical professor at the Icahn School of Medicine at Mount Sinai in New York.
He says GHK-Cu helps bolster collagen, part of the "scaffolding of the skin," and is on par with other topicals, like those containing Vitamin C and antioxidants.
However, pre-clinical research (not in humans) suggests the peptide holds promise beyond skin health.
For example, in animal studies, GHK-Cu was able to speed up wound healing and help repair organs, including fibrosis in the lungs.
Ladiges' experiments have also shown the "peptide stimulates a number of pathways that are associated with aging" and can alleviate some symptoms of Alzheimer's in mouse models.
Efforts to move this work on longevity into human trials – and get buy-in from drug companies – have proven fruitless, though.
GHK-Cu is a naturally-occurring molecule. That means it would be difficult for drug companies to patent it without creating a unique version and then paying for human trials. Ladiges says it would require huge investment, meaning "it's probably never going to get FDA approval."
Unregulated products
The emergence of GHK-Cu as a "beauty peptide" – and a staple of looksmaxxing content on social media – has fed a stream of peptide-curious patients who are now asking their doctors for guidance.
Does injecting it actually work better?
Goldberg says it's possible there are added benefits – in part because the molecule doesn't easily penetrate deeper into the skin when applied as a topical.
But he and other dermatologists tell NPR they're advising patients to hold off from injecting anything. "I'm not going to sleep well at night, until the human studies are actually done," he says.
According to Ladiges, GHK-Cu is generally quite safe, based on animal studies. Among the potential risks of injection: overloading your system with too much copper or triggering a dangerous immune reaction.
Much of the worry centers on the fact that consumers are largely sourcing injectable formulations from unregulated suppliers, with no assurance about quality or dosage, says Dr. Marisa Garshick, at MDCS Dermatology.
"Whether or not it's even a copper peptide is always a concern," she says. "The stakes are much higher when you're injecting something."
Like other wellness peptides being taken as injectables, GHK-Cu currently exists in confusing regulatory limbo.
Compounding pharmacies in the U.S. aren't technically allowed to offer it for injection in humans, though the Trump administration has signaled that could soon change.
Earlier this summer, a panel that advises the Food and Drug Administration recommended the government reclassify half a dozen of these peptides. The group will meet again in February to review the evidence for GHK-Cu as an injectable among other peptides.
In the field
But for now it remains widely available on the grey market – and the risks of unsupervised use are abundantly clear to Erik Marks, a doctor of nursing practice who runs a wellness and longevity clinic in the Seattle area called Vitality Medical PNW.
He says most of his consults about GHK-Cu are with patients who've already purchased it from an online seller and injected it on their own, only to then worry about the safety.
The issues he sees range from injection site irritation and infections to more serious problems affecting the liver.
"They don't feel right, something's wrong, their liver enzymes are elevated, copper is elevated – they've been injecting way too much," says Marks. "They haven't been checking lab work or anything."
In those circumstances, it's unclear whether copper peptides, or some other undisclosed substances or impurities are responsible. However, Marks does offer GHK-Cu both as a serum and cream and occasionally as an injection, usually mixed with other peptides aimed at tissue repair and inflammation.
He says he buys his products from a licensed compounding pharmacy in the U.S. that offers the peptide despite the current restrictions.
In Marks' clinical experience, the topicals work much better for skin and hair growth – and injecting copper peptides tends to have minimal impact.
"I think the jury is still out on the effects of it," he says. "People need to understand these peptides are not silver bullets to fix health."
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