Evidence Level
Strong
Collagen peptide supplementation for skin health is supported by a growing body of well-designed clinical trials. A comprehensive systematic review by de Miranda et al. (2021) analyzed 19 studies totaling 1,125 participants and found that hydrolyzed collagen at 2.5-10 g/day significantly improved skin hydration, elasticity, and wrinkle metrics compared to placebo. Proksch et al. (2014) demonstrated in two separate RCTs that specific collagen peptides improved skin elasticity and reduced wrinkle volume within 4-8 weeks. Mechanistic studies show that collagen-derived dipeptides (Pro-Hyp and Hyp-Gly) accumulate in skin tissue and stimulate fibroblast proliferation and hyaluronic acid production, explaining the clinical benefits observed.