Study
GHK-Cu — in placebo-controlled clinical studies summarized by Pickart et al. (2015, BioMed Research International), topical copper peptide formulations improved visible signs of photoaging, including skin laxity, fine lines, wrinkle depth, skin density and thickness. In one 12-week facial study, 71 women with mild to advanced photoaging showed improvements in skin appearance after using a GHK-Cu cream.
Palmitoyl Pentapeptide-4 — in a 2023 double-blind randomized clinical trial, women using a Palmitoyl Pentapeptide-4 cream for 8 weeks showed improvement in several measures of crow’s-feet and periorbital skin aging compared with placebo.