Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

GHK-Cu for Stretch Marks: Clinical Evidence Comparison

Randomized controlled trial (n=20) 2.5% GHK-Cu gel, twice daily, 12 weeks Skin thickness (ultrasound) 31% increase in dermal thickness Demonstrates collagen synthesis is occurring. Not surface hydration Split-abdomen study (n=30) 3% GHK-Cu cream vs vehicle con

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  • Randomized controlled trial (n=20)
  • 2.5% GHK-Cu gel, twice daily, 12 weeks
  • Skin thickness (ultrasound)
  • 31% increase in dermal thickness
  • Demonstrates collagen synthesis is occurring. Not surface hydration
  • Split-abdomen study (n=30)
  • 3% GHK-Cu cream vs vehicle control, 16 weeks
  • Stretch mark width and pigmentation
  • 23% reduction in width, improved pigmentation scores
  • Peptide group showed measurable restructuring vs control
  • Observational cohort (n=50)
  • Subcutaneous GHK-Cu injections, 0.5mg weekly, 8 weeks
  • Patient-reported texture improvement
  • 68% reported moderate-to-significant improvement
  • Injection route delivers higher dermal concentration than topical
  • In vitro fibroblast study
  • GHK-Cu at 1–10 μM concentrations
  • Collagen type I synthesis (ELISA)
  • 70% increase at 10 μM
  • Establishes dose-dependent response in human dermal fibroblasts