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SKIN & BEAUTYPEPTIDE PROFILE

Collagen Dipeptide

Also known as Pro-Hyp, Hyp-Gly, Prolyl-Hydroxyproline, Hydroxyproline-Glycine, Collagen hydrolysate fragments

Collagen dipeptides, principally Pro-Hyp (Prolyl-Hydroxyproline) and Hyp-Gly (Hydroxyproline-Glycine), are the primary bioavailable fragments generated during digestion of hydrolyzed collagen supplements. These short peptides are detectable in human plasma after oral ingestion and are believed to be the active agents responsible for the skin, joint, and bone benefits attributed to collagen supplementation.

Last updated April 10, 2026

TL;DR

Quick summary

Collagen dipeptides (Pro-Hyp and Hyp-Gly) are the primary bioavailable fragments from hydrolyzed collagen supplements. They reach measurable plasma concentrations after oral intake and directly stimulate fibroblasts to produce collagen and hyaluronic acid, supporting skin and joint health.

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Overview

Collagen dipeptides, principally Pro-Hyp (Prolyl-Hydroxyproline) and Hyp-Gly (Hydroxyproline-Glycine), are the primary bioavailable fragments generated during digestion of hydrolyzed collagen supplements. These short peptides are detectable in human plasma after oral ingestion and are believed to be the active agents responsible for the skin, joint, and bone benefits attributed to collagen supplementation.

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Mechanism of action

Pro-Hyp and Hyp-Gly survive intestinal digestion intact and are absorbed into circulation. They act on dermal fibroblasts to stimulate type I collagen and hyaluronic acid synthesis, and on chondrocytes to promote cartilage matrix production. Pro-Hyp has been shown to activate fibroblast proliferation and migration. These dipeptides may also act as chemotactic signals that recruit fibroblast precursors to the dermis. The hydroxyproline content is unique to collagen proteins, explaining the specificity of these fragments.

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Dosing protocols

PurposeRouteDosageFrequency
skin and joint supportoral250010000 mgonce daily (as hydrolyzed collagen providing these dipeptides)

Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.

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Research summary

Human pharmacokinetic studies confirm that Pro-Hyp reaches measurable plasma concentrations (0.5–10 µM) after oral hydrolyzed collagen intake. Controlled clinical trials of hydrolyzed collagen supplements report improvements in skin hydration, elasticity, and wrinkle depth over 8–12 weeks. Joint pain reduction in athletes has been shown in several placebo-controlled trials. Pro-Hyp specifically has demonstrated in vitro fibroblast-stimulating activity consistent with observed clinical benefits.[1][2][3][4]

📄This section cites 4 peer-reviewed sources. View all references →
§ 04b

Evidence grading

Each claimed benefit is graded by the strength of available evidence. Grades reflect study quality, not effect size.

strong
Pro-Hyp reaches measurable plasma levelsMultiple human pharmacokinetic studies confirming 0.5-10 micromolar plasma appearance
moderate
Improves skin hydration and elasticityMultiple placebo-controlled trials of hydrolyzed collagen over 8-12 weeks
moderate
Stimulates fibroblast proliferation and migrationConsistent in vitro fibroblast studies and ex vivo skin assays
moderate
Reduces joint pain in athletesSeveral placebo-controlled RCTs of hydrolyzed collagen in athletes
strong
Survives intestinal digestion intactHuman plasma measurement after oral ingestion confirms intact absorption

Strong = multiple RCTs · Moderate = limited trials or observational · Preliminary = animal or in vitro only · Insufficient = anecdotal or no published data

§ 05

Side effects

Mild GI discomfort
Rare allergic reaction in shellfish/fish-derived collagen products

Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.

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Common stacks

Peptides commonly paired with Collagen Dipeptide for synergistic effects.

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Sourcing & access

Research compound

Collagen Dipeptide is classified as a research compound. Regulatory status varies by jurisdiction. Always verify current legal status and source from vendors providing third-party certificates of analysis (COA).

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Frequently asked questions

Collagen dipeptides, primarily Pro-Hyp (Prolyl-Hydroxyproline) and Hyp-Gly (Hydroxyproline-Glycine), are the small bioactive fragments produced during digestion of hydrolyzed collagen supplements. They are the active agents responsible for collagen supplement benefits.

Pro-Hyp and Hyp-Gly survive intestinal digestion and are absorbed into circulation. They stimulate dermal fibroblasts to produce type I collagen and hyaluronic acid, promote chondrocyte cartilage matrix production, and may act as chemotactic signals recruiting fibroblast precursors to the dermis.

Collagen dipeptides are classified as GRAS (Generally Recognized as Safe) dietary supplement ingredients. Side effects are minimal, limited to mild GI discomfort and rare allergic reactions in people sensitive to shellfish or fish-derived collagen sources.

Clinical trials typically use 2,500 to 10,000 mg of hydrolyzed collagen daily, which provides the Pro-Hyp and Hyp-Gly dipeptides. Improvements in skin hydration, elasticity, and wrinkle depth are generally reported over 8 to 12 weeks of consistent use.

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Research references

  1. Pro-Hyp dipeptide absorption and plasma appearance after collagen hydrolysate ingestionIwai K, Hasegawa T, et al.J Agric Food Chem, 2005PubMed
  2. Collagen-derived dipeptides Pro-Hyp and Hyp-Gly stimulate fibroblast migration and proliferationOhara H, Matsumoto H, et al.Biosci Biotechnol Biochem, 2010PubMed
  3. Skin aging and the efficacy of oral hydrolyzed collagen: clinical trial evidenceProksch E, Segger D, et al.Skin Pharmacol Physiol, 2014PubMed
  4. Collagen peptides Pro-Hyp and Hyp-Gly: absorption in human subjects and skin fibroblast stimulationSugihara F, Inoue N, et al.J Cosmet Dermatol Sci Appl, 2012PubMed
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