Quick Comparison
| Copper Peptides (GHK-Cu) | Green Tea Extract (EGCG) | |
|---|---|---|
| Typical Concentration | Concentrations: 0.1-1% in skincare products. Apply once or twice daily. Do NOT use with strong acids (vitamin C at low pH, AHAs) — copper can catalyze free radical formation with ascorbic acid. Best used as a standalone PM treatment or mixed with peptide serums. | Topical: 1-5% green tea extract in formulations. Look for products with EGCG specifically listed. Oral: 400-800 mg green tea extract (standardized to EGCG) daily. Apply topical products before sunscreen for additional photoprotection. |
| Application | Topical (serum, cream). Blue/copper-colored products. Do not combine with low-pH vitamin C. | Topical (serum, cream, toner) or oral (supplement, tea). Topical is effective for localized skin benefits. |
| Research Papers | 10 papers | 9 papers |
| Categories |
Mechanism of Action
Copper Peptides (GHK-Cu)
GHK-Cu activates wound repair genes through copper-dependent transcription factor modulation. It stimulates fibroblasts to produce collagen types I, III, and V via COL1A1, COL3A1, COL5A1 upregulation, plus elastin, decorin, and glycosaminoglycans. Copper serves as cofactor for lysyl oxidase (collagen cross-linking). It attracts macrophages and mast cells releasing PDGF, TGF-beta, FGF. Promotes angiogenesis via VEGF. Uniquely activates MMP-2 and MMP-9 to break down damaged collagen and scar tissue — supporting healthy remodeling. Balanced anabolic-catabolic activity explains efficacy in anti-aging and scar revision. Avoid with vitamin C: copper catalyzes Fenton reactions oxidizing ascorbic acid.
Green Tea Extract (EGCG)
EGCG scavenges ROS (superoxide, hydroxyl radical, peroxynitrite) and chelates iron/copper that catalyze Fenton reactions. Inhibits MMP-2 (gelatinase A) and MMP-9 (gelatinase B) that degrade collagen types I, III, IV and elastin in photoaged skin — these enzymes are UV-upregulated via AP-1 and NF-kappa B. Reduces sebum by inhibiting 5-alpha reductase type 1 (testosterone to DHT conversion in sebaceous glands). Anti-inflammatory: NF-kappa B inhibition (I-kappa B degradation prevention), COX-2 suppression, TNF-alpha/IL-1beta reduction. Promotes keratinocyte differentiation via involucrin and filaggrin upregulation. Catechol structure enables dual antioxidant and metal-chelating activity. Topical EGCG reduces UV-induced erythema and prevents collagen degradation when used before sun exposure.
Risks & Safety
Copper Peptides (GHK-Cu)
Common
Blue/green tint to product (normal — copper color). Mild irritation.
Serious
Can be pro-oxidant when combined with vitamin C — avoid concurrent use.
Rare
Allergic reaction to copper.
Green Tea Extract (EGCG)
Serious
None topically. Oral high-dose EGCG supplements have rare liver toxicity reports.
Rare
Contact dermatitis.
Full Profiles
Copper Peptides (GHK-Cu) →
GHK-Cu is a naturally occurring copper complex that declines with age (60% reduction by age 60). It is one of the most potent wound-healing and skin-remodeling signals known — it stimulates collagen, elastin, glycosaminoglycan synthesis, and new blood vessel growth while simultaneously breaking down excess scar tissue. Used in both anti-aging and post-procedure recovery.
Green Tea Extract (EGCG) →
Epigallocatechin gallate (EGCG) is the primary polyphenol in green tea and one of the most potent topical antioxidants. It has been shown to reduce UV damage, decrease sebum production, reduce inflammation, and inhibit the enzymes that break down collagen and elastin. Green tea extract is one of the few antioxidants with evidence for both topical and oral skin benefits.