Supplements
Oral Collagen Peptides
Meta-analyses show small but real improvements in skin hydration and elasticity; industry funding muddies the water.
Also called: collagen powder · collagen peptides · marine collagen
Verdict — mixed
Real in part — the claim outruns what it actually does.
Evidence grade B
At least one good randomised trial, or consistent findings across controlled studies.
Mechanism
Hydrolyzed collagen di/tripeptides survive digestion and may act as signaling molecules stimulating fibroblast collagen synthesis.
Citations
- Oral collagen supplementation: a systematic review of dermatological applicationsJournal of Drugs in Dermatology · 2019
The full read
Pooled RCT data (10+ trials) shows statistically significant improvements in skin elasticity and hydration after 8–12 weeks. Caveats: most trials are manufacturer-funded, effect sizes are modest, and protein-sufficient diets may capture much of the benefit. Reasonable as a cheap adjunct; a poor substitute for tretinoin and SPF.
