A copper peptide your body makes naturally — and makes less of as you age.
GHK-Cu was first identified in human blood in 1973. Since then it has been the subject of decades of published research. This page is a plain-English summary of what that research has found, and what double-blind trials on the LifeWave X39 patch have actually measured.
Explore the research ↓GHK is a tiny peptide — just three amino acids linked together: glycine, histidine and lysine. It occurs naturally in the human body and has been found in blood, saliva and urine.
On its own it's called GHK. When it binds to copper — a mineral your body needs — it becomes GHK-Cu, sometimes written as copper tripeptide-1.
It was first isolated in 1973 by Dr. Loren Pickart, who noticed something curious: older liver cells behaved younger when bathed in blood from younger people. The factor responsible turned out to be this peptide. In 1977, researchers at Harvard confirmed its structure.
One detail sits at the centre of the whole GHK-Cu story: levels fall as we age. Published figures put GHK at roughly 200 ng/mL around age 20, declining to about 80 ng/mL by age 60 — a drop of more than half across adult life.
Across many peer-reviewed studies, GHK-Cu has been studied for a range of properties. Here is what that body of work describes.
In human skin-cell cultures, GHK-Cu stimulated collagen production. Reviews describe associations with skin firmness, elasticity, barrier-protein repair, and the appearance of fine lines and uneven texture.
Research describes GHK-Cu as one of the body's natural "repair signals" — a molecule released around tissue that needs rebuilding, studied for its role in remodelling and recovery.
Laboratory studies have examined GHK-Cu's effect on oxidative stress — the cumulative cellular wear associated with ageing — including its influence on markers of oxidative damage.
Some of the most-discussed research used gene-expression databases to show that GHK can shift the activity of large numbers of genes back toward patterns seen in younger, healthier tissue. It's worth being precise: these are gene-expression analyses of the molecule, not a claim that wearing anything edits your DNA.
A 2017 gene-expression study examined GHK's relationship to genes involved in nervous-system function and cognitive health markers.
In animal studies, copper-peptide complexes stimulated hair follicles, prompting interest in topical applications for hair density and growth cycles.
Each claim above corresponds to a source listed in the References section below.
Most GHK-Cu research is about the molecule. A smaller number of studies looked at the X39 patch specifically — a sealed, non-transdermal patch designed to reflect light back toward the skin, with the stated goal of prompting the body's own GHK-Cu rather than delivering anything into it.
Sixty adults were randomly assigned to wear an active or control patch. Researchers measured GHK-Cu in their blood at day 1, day 2 and day 7. The active group showed a statistically significant rise in blood GHK-Cu from day 2 to day 7 compared with the control group (p < 0.035 for concentration; p < 0.03 for total GHK-Cu).
A separate trial reported increases in several amino acids, alongside improvements in short-term memory (measured by a standard memory test), sleep quality, and self-reported vitality over the seven-day period.
The idea behind the X39 patch is called photobiomodulation — using specific wavelengths of light to influence the body's own biology. A familiar everyday example of light changing body chemistry: sunlight prompting your skin to make vitamin D.
Nothing passes from the patch into your skin. The patch is a closed, sealed unit.
It reflects certain wavelengths of light back toward the body, using your own body heat as the activation trigger.
The stated mechanism is encouraging the body's own GHK-Cu production — not supplying the peptide directly.