Vitamin CandCopper peptides
Can you use copper peptides with vitamin C?
CautionLimited evidence
It's best to use them at different times of day. Copper can speed up the oxidation of vitamin C, which may make both less effective.
Why
Copper ions are well known to speed up the breakdown of ascorbic acid, and vitamin C, as a reducing agent, can also change the form of copper in copper peptide products. How much this happens when the copper is held by the GHK peptide hasn't been studied on skin, so the evidence is limited. Keeping them in separate routines is an easy precaution.
How to use them
Use vitamin C in the morning, before broad-spectrum sunscreen, and copper peptides in your evening routine.
Sources
- 1Ultimate Vitamin C Skincare Guide Part 1: Ascorbic Acid · Lab Muffin Beauty Science (Michelle Wong, PhD), 2021
- 2Catalytic metals, ascorbate and free radicals: combinations to avoid · Radiation Research, 1996
- 3GHK-Cu as a Bioactive Metallopeptide and Drug-Delivery Cargo: Coordination Chemistry, Formulation Science, Therapeutic Evidence, and a Translational Roadmap · Pharmaceutics, 2026
General cosmetic information, not medical advice. Written with AI assistance from the sources above; updated October 2026.