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CYOU
HomeThe science

01Hero

Why trust this ingredient
The science behind CYOU

A triple-peptide repair complex.
Built around the peptide your skin already knows.

GHK-Cu is one of the most researched peptides in clinical dermatology — your body makes it naturally, and loses it with age. CYOU pairs 1% pharmaceutical-grade GHK-Cu with Matrixyl 3000 and a botanical repair complex to address collagen loss from multiple directions simultaneously.

94%
saw firmer skin in 4 weeks
10×
the GHK-Cu of most mass-market serums
33%
fewer deep forehead lines at 12 weeks
3
clinically studied peptide actives in one formula

02The problem

Create the need before the solution
Why it matters

Your GHK-Cu levels drop 60% between your 20s and 60s.

GHK-Cu is a naturally occurring copper peptide found in human plasma, saliva, and urine. In young skin it drives collagen synthesis, elastin production, and barrier repair. As levels fall with age, the skin loses its ability to self-repair — leading to fine lines, reduced firmness, and slower recovery from damage. This is the core mechanism CYOU was formulated to address.

Relative GHK-Cu skin levels by decade
20s
100%
30s
80%
40s
60%
50s
48%
60s
40%

03Mechanism of action

What it does — plain language
How GHK-Cu works in the skin

Three mechanisms. One peptide.

Stimulates collagen synthesis

GHK-Cu activates genes responsible for collagen I and III production — the structural proteins that give skin firmness and bounce. Clinical studies demonstrate measurable collagen density increases with consistent use at clinically active concentrations.

Accelerates barrier repair

GHK-Cu signals keratinocytes to proliferate and migrate, speeding skin recovery. Effective post-procedure (laser, microneedling, peels) and for skin that's been compromised by over-exfoliation or environmental stress.

Reduces inflammation

GHK-Cu modulates pro-inflammatory cytokines — calming chronic low-grade inflammation that accelerates skin ageing. Well tolerated by sensitive skin types who react to retinoids or exfoliating acids.

04Concentration

Core competitive argument
Why concentration matters

The research used 1–3% GHK-Cu. Most serums use 0.1%. CYOU uses 1% — and adds two more peptides.

The peer-reviewed studies on GHK-Cu used concentrations between 1–3%. Consumer products typically use it at 0.05–0.1% — a fraction of the clinically active level. CYOU uses pharmaceutical-grade GHK-Cu at 1% concentration, 10× the mass-market standard. And because collagen decline is multi-pathway, CYOU also includes Matrixyl 3000 (Palmitoyl Pentapeptide-4 + Palmitoyl Tetrapeptide-7) to support collagen synthesis and reduce cytokine-driven breakdown simultaneously.

Read referenced studies ↓
GHK-Cu concentration comparison
CYOUClinical
1%
The Ordinary
0.1%
Most others
0.05%
10×
the GHK-Cu of The Ordinary and most mass-market serums

05Clinical trial

IRB-approved data
IRB-approved clinical trial

12-week double-blind trial. Real results on real skin.

CYOU commissioned an independent, IRB-approved clinical trial — the same standard used in pharmaceutical research. 35 participants, twice daily use, results assessed by a blinded investigator at weeks 4, 8, and 12.

94%
saw visibly firmer skin
at week 4
89%
reported improved skin quality
at week 8
33%
fewer deep forehead lines
at week 12
83%
felt skin recovered & resilient
at week 12
Study type
Double-blind, IRB-approved
Participants
35 women, ages 38–62
Duration
12 weeks, twice daily
Assessment
Blinded investigator grading

06Full formula

Every ingredient, plain English
What's in it and why

Every ingredient has a job. Nothing is there for the label.

Hero active — copper peptide repair
The primary active the formula is built around
Copper Tripeptide-1 (GHK-Cu)1%
INCI: Copper Tripeptide-1 · CAS 89030-95-5

The hero active. A naturally occurring human peptide that stimulates collagen I and III synthesis, accelerates barrier repair, and modulates inflammation. At 1%, CYOU uses 10× the concentration of most mass-market serums. Pharmaceutical-grade purity — matching the concentration used in the clinical studies demonstrating measurable wrinkle reduction and firmness improvement.

Matrixyl 3000 — peptide support complex
Two signalling peptides that amplify collagen synthesis and slow collagen breakdown
Palmitoyl Pentapeptide-40.2%
Matrixyl · CAS 214047-00-4

Stimulates collagen I, III, and IV plus fibronectin and hyaluronic acid production. One of the most clinically studied cosmetic peptides — 20+ publications. Directly amplifies the collagen synthesis triggered by GHK-Cu.

Palmitoyl Tetrapeptide-70.2%
Matrixyl 3000 · CAS 221227-05-0

Signals the skin to reduce excess IL-6 — a key cytokine driver of collagen breakdown with age. Reduces degradation at the source, protecting the new collagen the other peptides are building.

Botanical repair complex
Two clinically evidenced plant extracts — barrier recovery, anti-inflammatory, brightening
Centella Asiatica Extract2%
Gotu kola · CAS 84776-24-9

One of the most researched plant actives in dermatology. At 2%, stimulates collagen synthesis, supports wound healing, and has strong anti-inflammatory action. Calms reactive skin while the peptide complex does repair work — a natural pairing with GHK-Cu for sensitive or compromised skin.

Portulaca Oleracea Extract2%
Purslane · CAS 90083-07-1

Rich in omega-3 fatty acids and antioxidants. Inhibits melanin synthesis and reduces oxidative stress. Supports the skin barrier and adds a brightening effect. Anti-inflammatory — reinforces the soothing action of Centella.

Hydration & delivery system
Humectants that maintain moisture and maximise active absorption
Trehalose2%
CAS 99-20-7

Protects proteins and cell membranes from degradation. A powerful humectant — holds moisture longer than glycerin alone. Also stabilises the peptide actives in the formula.

Glycerin5%
CAS 56-81-5

Backbone humectant — draws water from the air into the skin. At 5%, provides meaningful hydration without heaviness or greasiness.

Butylene Glycol8%
CAS 107-88-0

Humectant and solvent. Improves skin feel and absorption. At 8%, ensures smooth, non-sticky application and helps carry peptides into the skin.

Tremella Fuciformis Extract0.35%
Snow mushroom · CAS 778577-37-0

Holds up to 500× its weight in water — outperforming hyaluronic acid for moisture retention in some studies. Forms a flexible, breathable film on the skin surface.

Sodium Hyaluronate0.15%
CAS 9067-32-7

Low molecular weight HA that penetrates beyond the surface for deeper hydration. Acts as a carrier vehicle for the peptide actives.

Serine0.15%
CAS 56-45-1

An amino acid found naturally in skin's NMF (Natural Moisturising Factor). Supports the barrier and enhances moisture retention alongside the other humectants.

Antioxidant & soothing support
Environmental protection and visible redness reduction
Gentiana Scabra Root Extract0.5%
Japanese gentian · CAS 95193-52-5

Potent antioxidant and anti-inflammatory. Calms redness and neutralises free radical damage from UV and pollution. Complements the anti-inflammatory action of Centella.

Paeonia Albiflora Root Extract0.5%
White peony root · CAS 84929-40-8

Brightening and anti-inflammatory. Inhibits melanin synthesis and reduces visible redness. Works alongside Portulaca to even skin tone while the peptides address firmness and texture.

07Free from

Clean formula
What's not in it
Fragrance
Essential oils
Parabens
Silicones
Sulfates
Drying alcohols
Mineral oil
Artificial colour

08Formulation quality

How do I know this is legit
Formulation standards

Pharmaceutical-grade ingredients. Stability-tested formula.

GHK-Cu is a sensitive peptide — it degrades in poorly formulated products before it reaches the skin. CYOU's formula was developed with cosmetic chemists to maintain peptide stability and bioavailability throughout the product's shelf life.

  • pH optimised for GHK-Cu stability (pH 6.5–7.0)
  • Trehalose included to stabilise the peptide complex
  • Opaque packaging — protects actives from UV degradation
  • Fragrance and essential oil free — no competing irritants
  • Shelf-stable 24 months unopened, 12 months after opening
  • GMP-certified Australian manufacturing facility
Certifications & standards
Dermatologist tested
Tested and approved by a board-certified dermatologist
Cruelty-free
No animal testing at any stage of development
IRB clinical trial
Independent, ethics-approved human clinical testing
GMP manufactured
Produced in a GMP-certified Australian facility

09INCI

Compliance + transparency
Full INCI (label-accurate order)

Aqua, Butylene Glycol, Glycerin, Trehalose, Centella Asiatica Extract, Portulaca Oleracea Extract, Copper Tripeptide-1, 1,2-Hexanediol, Gentiana Scabra Root Extract, Hydroxyacetophenone, Pentylene Glycol, Tremella Fuciformis (Mushroom) Extract, Xanthan Gum, Palmitoyl Tetrapeptide-7, Palmitoyl Pentapeptide-4, Serine, Sodium Hyaluronate, Paeonia Albiflora Root Extract.

Referenced studies
  1. 1.Pickart L. The human tri-peptide GHK and tissue remodeling. J Biomater Sci Polym Ed. 2008;19(8):969–988.
  2. 2.Finkley MB et al. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Biomed Res Int. 2015.
  3. 3.Leyden JJ et al. The effect of a topical GHK-Cu containing formulation on the appearance of fine lines and wrinkles. Cosmetics. 2018.
  4. 4.Sederma. Matrixyl 3000 clinical dossier. Multiple publications 2002–2018.
  5. 5.CYOU independent clinical trial. IRB No. [XXXX]. 35 participants, 12 weeks, twice daily use. 2026. Full data available on request.
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