Do collagen supplements improve aging skin?

Background

Collagen peptides are protein fragments rich in glycine, proline and hydroxyproline, sold to improve skin, joints and hair.

What the human research shows

• A 2026 meta-analysis of 19 randomized trials (1,341 people) found oral peptides improved skin hydration and brightness.
• Wrinkle reduction was modest overall, and effects on skin elasticity were inconsistent and mostly not significant.
• Results varied widely between trials, and several had unclear or high risk of bias. The authors judged the evidence insufficient for definitive conclusions.

What we still don’t know

• Whether benefits come from collagen specifically or simply from extra protein.
• Long-term effects, and effects on joints and hair, which have weaker evidence.

Safety and status

Side effects in trials were mild, mainly digestive. Supplements are not reviewed by the FDA before sale.

Sources

1. Oral and topical peptides for skin aging: systematic review and meta-analysis of randomized controlled trials. Frontiers in Medicine, 2026
2. VALREXA spotlight: Glycine, the collagen amino acid

Last reviewed November 7, 2026. Educational only; not medical advice, and not a recommendation to take any drug or supplement. Talk to a clinician before starting anything.