The Sustained Effects of Bioactive Collagen Peptides on Skin Health: A Randomized, Double-Blind, Placebo-Controlled Clinical Study

Wang Y, Zhu W, Luo W, Ma Y, Zhou Y · Journal of Cosmetic Dermatology

Dermal density, hydration and transepidermal water loss improved against placebo at 12 weeks and the improvements held through a 4-week washout, which is the interesting part: the effect did not wash out on the timescale a plasma-peptide explanation would predict. Dermal thickness rose; the epidermis did not change.

Population

Healthy women

Intervention

5 g bioactive collagen peptides daily for 12 weeks, followed by a 4-week washout

Comparator

Placebo

Limitations

Skin rather than joint. Three of five authors are employees of Shanghai Meifute Biotechnology, which supplied the product. The persistence of the effect through washout is equally consistent with an unblinded expectation effect that also persists.