Collagen Peptides
Not one supplement but two, doing different jobs under the same name.
Collagen is the body's most abundant structural protein, found in skin, tendons, and cartilage, and supplement forms fall into two genuinely different categories. Hydrolysed collagen peptides are broken down into small units the body absorbs and uses as raw material for its own collagen production, the form most studied for skin elasticity and joint comfort. Undenatured type II collagen works completely differently, in small daily doses, by training the immune system to tolerate joint cartilage rather than attack it, an approach used mainly for joint health rather than skin. Marine and bovine collagen differ mainly in sourcing and amino acid profile rather than mechanism.
Reference values
Daily reference values from official nutrition authorities. These are population reference figures, not personal recommendations.
| RDA | Upper limit | Source |
|---|---|---|
| 10000 mg | 30000 mg | UK |
Forms and bioavailability
Not all forms are absorbed equally. The form on your supplement label affects how much your body can actually use.
| Form | Absorption | With food | Timing | Evidence |
|---|---|---|---|---|
| hydrolysed collagen peptides | Typical | Either | Either | Likely |
| undenatured collagen type II | Typical | Either | Either | Likely |
| marine collagen | Typical | Either | Either | Possible |
| bovine collagen | Typical | Either | Either | Possible |
Stack Almanac tracks which collagen type and form you're taking, since hydrolysed peptides and undenatured type II are pursuing different goals despite the shared name on the tub.
Track your Collagen Peptides in Stack Almanac
Last reviewed: 2026-07-08. Reference values are adult-general RDAs from UK. Individual needs may vary. This page is for informational purposes only and is not a substitute for professional medical advice.