SkincareAddiction

Background

Collagen supplements are promoted to help aging skin. However, no meta-analysis of randomized controlled trials (RCTs) has examined their effects by funding source and study quality, which may influence outcomes.

Methods

PubMed, Embase, and Cochrane Library were searched from inception to June 14, 2024.

Results

A total of 23 RCTs with 1474 participants were analyzed. In a meta-analysis of all 23 RCTs, collagen supplements significantly improved skin hydration, elasticity, and wrinkles. However, in the subgroup meta-analysis by funding source, studies not receiving funding from pharmaceutical companies revealed no effect of collagen supplements for improving skin hydration, elasticity, and wrinkles, while those receiving funding from pharmaceutical companies did show significant effects. Similarly, high-quality studies revealed no significant effect in all categories, while low-quality studies revealed a significant improvement in elasticity.

Conclusions

There is currently no clinical evidence to support the use of collagen supplements to prevent or treat skin aging.