Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

GHK-Cu Cosmetic Complexion Results Timeline Comparison

Week 1–4 Improved radiance, reduced dullness, smoother microtexture Antioxidant enzyme activation (SOD, catalase) reduces oxidative stress; keratinocyte turnover normalizes Subjective self-assessment; profilometry for surface roughness Surface changes are real

This source-based comparison does not add ratings or recommend a winner.

  • Week 1–4
  • Improved radiance, reduced dullness, smoother microtexture
  • Antioxidant enzyme activation (SOD, catalase) reduces oxidative stress; keratinocyte turnover normalizes
  • Subjective self-assessment; profilometry for surface roughness
  • Surface changes are real but don't reflect deeper structural work yet. Continue protocol
  • Week 4–8
  • More even tone, reduced appearance of surface irregularities, hydration improvement
  • Barrier lipid protection from ROS neutralization; reduced TEWL; melanocyte activity modulation
  • Colorimetry for tone uniformity; corneometry for hydration
  • This phase represents maximum surface improvement. Structural depth gains require longer commitment
  • Week 8–12
  • Early firmness changes, subtle elasticity improvement
  • New collagen synthesis reaches measurable levels; procollagen processing and secretion into ECM begins
  • High-frequency ultrasound for dermal thickness; cutometry for elasticity
  • Transition phase. Structural gains begin but haven't matured fully into visible wrinkle reduction yet
  • Week 12–16
  • Visible wrinkle depth reduction, improved skin firmness, sustained tone evenness
  • Mature collagen integration into dermal matrix; lysyl oxidase cross-linking strengthens mechanical support
  • Wrinkle depth via 3D optical scanning; elasticity via cutometry
  • Full structural remodeling phase. Results plateau and require maintenance dosing to sustain
  • Week 16+
  • Maintenance of achieved improvements with continued use; gradual regression if stopped
  • Collagen turnover rates return to baseline without continued copper-peptide signaling
  • Same as week 12–16 methods
  • Discontinuation leads to gradual loss of structural gains over 6–12 months as collagen degrades naturally