"Types of collagen", "type 2 collagen" and "undenatured type II collagen" together draw about 7,900 searches a month, and supplement shelves answer with labels promising "five types" or "types I, II, III, V and X". This page sets out what the types are, why "type II" names two products that work differently, and what US multi-collagen labels actually disclose. It reports labels and trials; it does not suggest a product or an amount (how we work).
The body has 28 types; labels name five
Collagen is not one protein but a family. 28 members share at least one triple-helical domain, the rope-like structure that gives collagen its strength (Ricard-Blum, Cold Spring Harb Perspect Biol 2011, PMID 21421911). Supplements name five:
| Type | Where it mainly sits | How it is sold |
|---|---|---|
| I | skin, tendon, ligament, bone — the most abundant | hydrolysed peptides from bovine hide or fish skin, in grams |
| II | cartilage | undenatured (≈40 mg) or hydrolysed chicken cartilage |
| III | alongside type I in skin and blood vessels | usually comes with type I from bovine hide |
| V | minor partner of type I in skin and other tissues | named on multi-collagen labels |
| X | cartilage at the growth zone next to bone | named on multi-collagen labels |
The muscle, tendon and joint trials of collagen peptides used type I (or I and III) hydrolysates at 5 to 15 g a day; their table is on how much collagen per day. A hydrolysed collagen is cut into short peptides before it is sold and digested further in the gut, so its "type" mostly describes the source tissue rather than a structure that survives intact.
Type II is two different products
Undenatured type II collagen keeps its native structure. It comes from chicken sternum cartilage and is taken at about 40 mg a day — a few hundredths of a gram. It is not proposed to supply building blocks; the proposed mechanism is oral tolerance, in which small amounts of an intact protein in the gut damp down the immune response to it elsewhere. A 2025 review of this product for knee osteoarthritis included 8 clinical studies and 1 study with both pre-clinical and clinical parts, and reports 40 mg a day as the studied amount (Gupta and Maffulli, Ann Med 2025, PMID 40253594); the first author's affiliation is a biologics company. The trial by trial record, including the comparison with glucosamine and an independent trial that found no difference, is on collagen for joints.
Hydrolysed type II collagen is the same cartilage broken into peptides and sold in larger amounts, often with chondroitin and hyaluronic acid that come from the same tissue. It is a protein supplement, like type I peptides, and has its own small trial record.
So a label saying "type II" without "undenatured" or an amount does not tell a buyer which of these two it is.
What 134 multi-collagen labels disclose
We read every on-market label in the US government's supplement register (the NIH Dietary Supplement Label Database) that matched "multi collagen" or "types I, II, III" on 2026-10-14: 134 labels from 58 brands.
| Claim or disclosure (134 labels) | Labels |
|---|---|
| Claim all five types: I, II, III, V and X | 89 |
| Claim three or four types | 38 |
| State how much of each type a serving contains | 0 |
| List eggshell membrane | 103 |
| List a bovine source | 126 |
| List a marine or fish source | 126 |
| List chicken | 118 |
Type counts come from a text search of each label's ingredient list and statements; a label naming a type anywhere counts once. Sources overlap: most list three or four.
The pattern is a blend of four animal sources — bovine hide, fish skin, chicken cartilage and eggshell membrane — with the types attributed to the blend as a whole. Eggshell membrane is a different material again: a 2024 systematic review describes it as mainly type I collagen with chondroitin sulfate, dermatan sulfate and hyaluronic acid (Bone Reports 2024, PMID 38872992). No label we read gives a buyer a way to know how much type V or type X a serving holds.
The amounts. 57 of the 134 labels declare a collagen or collagen-blend amount per serving. Their median is 1.6 g, and 45 are under 2.5 g, many of them capsules. The hydrolysed-collagen joint trials used 5 to 10 g a day and the muscle trials 15 g. The same gap between capsules and trial amounts is counted on how many capsules match a scoop.
The one trial of a mixed-type product
A PubMed search on 2026-10-14 found one randomised trial of a product combining several types: type I and III peptides with hydrolysed type II, given to 32 people with meniscus problems (17 on the product, 15 on placebo) for eight weeks. Pain, quality-of-life and kinesiophobia scores improved; back strength, proprioception, balance and most functional tests did not; the leg-strength difference was reported at p = 0.057 (Genç et al., BMC Musculoskelet Disord 2025, PMID 39755603). The trial tested one branded product against placebo; it did not compare a mix of types with any single type, and it was registered after the fact. No trial we found compares a multi-type product with a single-type one.
Where marine and grass-fed fit
"Marine" and "bovine" describe the source animal, not a different collagen type: both are mostly type I. What separates sources in practice is allergen labelling and the trials each was used in; the source comparison is a separate page, and what "grass-fed" does and does not certify on a collagen tub is on grass-fed collagen. Plant-based "collagen" contains no collagen of any type (vegan collagen).
What this page cannot tell you
- Type counts are from label text in the federal register, which holds many but not all US products, and are the makers' own statements; nobody assayed these products for this page.
- Whether collagen type matters once a hydrolysate is digested has not been tested head to head in people.
- Nothing here suggests a product, type or amount. Fish, egg or beef allergies are a reason to read the source list; joint pain and allergies belong with a clinician, and collagen's reported problems are collected on collagen side effects.
Sources
- Ricard-Blum S. The collagen family. Cold Spring Harb Perspect Biol 2011;3(1):a004978 — PMID 21421911
- Gupta A, Maffulli N. Undenatured type II collagen for knee osteoarthritis. Ann Med 2025;57(1):2493306 — PMID 40253594 · doi:10.1080/07853890.2025.2493306
- Eggshell membrane as promising supplement to maintain bone health: a systematic review. Bone Rep 2024 — PMID 38872992
- Genç AS, Yılmaz AK, Anıl B, et al. The effect of supplementation with type I and type III collagen peptide and type II hydrolyzed collagen on pain, quality of life and physical function in patients with meniscopathy. BMC Musculoskelet Disord 2025;26:17 — PMID 39755603 · doi:10.1186/s12891-024-08244-w
- NIH Office of Dietary Supplements. Dietary Supplement Label Database — API v9, labels matching "multi collagen" or "types I, II, III", 134 on-market labels read on 2026-10-14 — dsld.od.nih.gov
- PubMed searches for multi-type collagen trials, run 2026-10-14.