Study on the Multiple Efficacies of Vitamin C Serum in Anti‐Glycation, Anti‐Carbonylation, Antioxidation, and Anti‐Inflammation of Human Skin Based on In Vivo Tests

BACKGROUND: Skin glycation, oxidation, carbonylation, and excessive inflammation are well-recognized factors contributing to skin aging and pigmentation. Previous in vitro studies have confirmed vitamin C's antioxidant, anti-glycation, and anti-inflammatory properties, but its in vivo effects remain to be further verified. AIMS: To investigate the in vivo effects of topical vitamin C serum on skin anti-glycation, anti-carbonylation, antioxidation, and anti-inflammation, and to provide evidence for its anti-aging and skin-brightening applications. PATIENTS/METHODS: A randomized, double-blind, controlled trial was conducted, enrolling 66 healthy Chinese females, with 31 in the blank group and 35 in the topical group. Participants applied 10% vitamin C serum for 12 weeks. Skin glycation, carbonylated protein content, interleukin-1α (IL-1α) levels, free radical scavenging capacity, and skin color parameters were evaluated before and after treatment. RESULTS: After 12 weeks, the topical group showed significant improvements: AGEs reduced by 17.65%, carbonylation fluorescence intensity decreased by 49.22%, IL-1α content dropped by 58.73%, and ABTS free radical scavenging rate increased by 12.14%. Skin yellowness (b* value) and redness (a* value) decreased by 6.13% and 16.46%, respectively (all p < 0.001). CONCLUSIONS: Topical 10% vitamin C serum can effectively mitigate skin glycation, carbonylation, and inflammation, enhance skin antioxidant capacity, and improve skin color, supporting its clinical value in anti-aging and skin-brightening.