# Collagen peptides (hydrolysed collagen)

Collagen peptides are also called hydrolysed collagen or collagen hydrolysate. They are made by enzymatically breaking down animal collagen into small fragments, about 2 to 5 kDa. The source is usually bovine, porcine, or fish skin and bone. Iwai and colleagues (2005) found that two hydroxyproline-containing dipeptides, Pro-Hyp and Hyp-Gly, appear in human blood after you swallow them. That is evidence they are absorbed as more than just free amino acids. Randomized trials of 2.5 to 10 g a day, for 8 to 24 weeks, show modest gains in skin hydration and elasticity. And meta-analyses report less pain in knee osteoarthritis. Effects on bone density and tendon healing are less consistent. In the EU, collagen peptides are regulated as food, with no EU-authorized health claim.

## Sources

- Iwai K, Hasegawa T, Taguchi Y, et al.. (2005). Identification of food-derived collagen peptides in human blood after oral ingestion of gelatin hydrolysates. Journal of Agricultural and Food Chemistry. https://doi.org/10.1021/jf050206p
- de Miranda RB, Weimer P, Rossi RC. (2021). Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta-analysis. International Journal of Dermatology. https://doi.org/10.1111/ijd.15518
- Lugo JP, Saiyed ZM, Lane NE. (2023). Analgesic efficacy of collagen peptide in knee osteoarthritis: a meta-analysis of randomized controlled trials. Journal of Orthopaedic Surgery and Research

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_Canonical: https://longevity-switzerland.com/en/glossary/collagen-peptides · Part of Longevity Cities · Updated 2026-06-22_