Efficacy and safety of hydrolyzed collagen supplementation on skin health outcomes: a systematic literature review of randomized controlled trials (opens in new tab)

Oral hydrolyzed collagen (HC) supplementation is widely recommended for improving age-related skin changes. However, clinical evidence remains inconsistent. This systematic literature review (SLR) synthesizes the findings from randomized controlled trials (RCTs) evaluating the efficacy, safety, and quality of life (QoL) outcomes of HC supplementation in adults. We systematically searched Embase, MEDLINE, and MEDLINE In-Process from inception through April 1, 2023, to identify RCTs assessing o...