Peptides are one of the most researched ingredient categories in modern beauty — and one of the least understood. Here’s a plain-language look at what they are, what the research actually says, and why we built RootMira around one of them.
What are peptides?
Peptides are short chains of amino acids — the building blocks of proteins like collagen, elastin, and keratin. Your skin and hair are largely made of these proteins, which is why cosmetic scientists have spent decades studying how specific peptides behave in skincare and haircare formulas.
Copper peptides: the blue ones
Copper peptides get their vivid blue color from copper bound to a tiny peptide chain. They’re among the most studied peptides in beauty science.
GHK-Cu (Copper Tripeptide-1)
The original copper peptide, identified in human plasma in the 1970s. It has the largest body of research of any cosmetic peptide — studied for decades in skin science in connection with collagen, skin firmness, and the appearance of fine lines.
AHK-Cu (Copper Tripeptide-3)
A close relative of GHK-Cu with one amino acid swapped (alanine for glycine). Researchers have focused AHK-Cu studies on hair: laboratory studies link it to dermal papilla cell activity — the cells at the base of the hair follicle. It’s a newer ingredient with early-stage research, and it’s the copper peptide we chose for the RootMira mask.
Other peptides you’ll see in beauty
- Signal peptides (e.g. Matrixyl / palmitoyl pentapeptide) — used in skincare to support the look of firmer skin.
- Neurotransmitter-affecting peptides (e.g. Argireline / acetyl hexapeptide-8) — used in anti-wrinkle formulas for the appearance of smoother expression lines.
- Carrier peptides — peptides that help deliver trace minerals like copper to the skin.
Peptides for hair vs. skin
Most peptide research centers on skin. Hair-focused peptides like AHK-Cu are a newer frontier — the science is promising but earlier-stage, mostly laboratory and cell studies so far. We follow the research closely and formulate around what it supports.
Why RootMira uses AHK-Cu
We built the RootMira Root & Scalp Nourishing AHK-Cu Copper Peptide Hair Mask around AHK-Cu because the early hair-follicle research points in an exciting direction — and we pair it with classic nourishers like shea butter, coconut oil, rosemary, and aloe. Shop the mask.
Note: RootMira products are cosmetics, not medicines. This page shares general ingredient information, not medical advice.