Influence of collagen peptide supplementation on visible signs of skin and nail health and -aging in an East Asian population: A double blind, randomized, placebo-controlled trial

Vleminckx S, Virgilio N, Asserin J, Prawitt J, Silva CIF · Journal of Cosmetic Dermatology

The nearest thing to a placebo-controlled nail trial in the collagen literature, and nail is a secondary endpoint measured as colour rather than growth or breakage. Dermis density and skin moisture improved against placebo at 84 days. Nail colour, skin elasticity, wrinkle visibility and beauty perception improved by day 28 in the collagen group while the placebo group reached the same point by day 84 — a difference in timing rather than in destination.

Population

Healthy East Asian women aged 43-65, all using a standardized face cream for 28 days before and throughout

Intervention

5 g collagen peptides daily for 84 days

Comparator

5 g maltodextrin placebo

Limitations

Nail colour is not nail strength, thickness or growth rate, so this does not test the brittleness claim. Several outcomes converged between groups by the end of the study. Authors are employed by Rousselot, a collagen manufacturer, and the tested peptide is its product.