A recent meta-analysis by Myung & Park (2025) claims there is “no clinical evidence” that oral collagen supplements help aging skin. This bold conclusion is based on subgroup analyses suggesting that collagen only works in industry-funded or lower-quality trials, disappearing in independent or high-quality studies. However, a closer examination reveals several methodological issues in that review, including a very small number of truly independent trials (many of which used suboptimal doses and durations) and the dismissal of positive findings from rigorous studies.
