Tier 3 — preclinical

Current insights into collagen type I

Ruth Naomi, Pauzi Muhd Ridzuan, Hasnah Bahari
Polymers 2021 13(16):2642

Bibliography

PubMed
PMID 34451183
PubMed Central
PMC8399689
DOI
10.3390/polym13162642
Funding
Funding statement (verbatim): "This study was funded by Research Management Centre (RMC) UPM for APC payment. The funder does not have any contribution and decision to publish or preparation of the manuscript."
Competing interests
Competing interests statement (verbatim): "The authors declare no conflict of interest." All three authors affiliated with Universiti Putra Malaysia (Department of Human Anatomy) and Estika Research Centre (Kuala Terengganu, Malaysia) — academic institutions with no commercial industry ties surfaced. Funding limited to article processing charge only, with explicit statement of no funder involvement in manuscript preparation. Clean commercial-independence profile.

Study snapshot

DesignComprehensive narrative review covering structure, availability, native synthesis, extraction methods, physicochemical characteristics, applications across pharmaceutical, cosmeceutical, regenerative medicine, and clinical fields
ModelNot applicable — review paper. Covers evidence from prior 5 years primarily.
SampleNot applicable
InterventionNot applicable
DurationReview methodology; covers literature primarily from the prior 5 years to the 2021 publication date
EndpointsComprehensive coverage of: molecular structure of collagen type I; sources (marine, bovine, porcine, chicken, egg); native biosynthesis pathway; current extraction and processing methods; physicochemical properties; applications across pharmaceutical, cosmeceutical, regenerative medicine, and clinical fields; biomarker overview

What the study showed, in plain terms

Collagen is a major structural protein family with 28 recognized types. Type I collagen is the dominant fibrillar collagen in tissues such as skin, bone, tendon, cornea and fascia.

This 2021 narrative review covers type I collagen structure, biosynthesis, animal and marine sources, extraction methods, physicochemical properties and applications in pharmaceutical, cosmeceutical, regenerative-medicine and biomaterials settings.

The paper is best used as a foundational biology reference rather than evidence that oral collagen supplementation improves a clinical outcome. Its wording that type I collagen makes up '90% of the human body' is imprecise and should not be repeated as meaning 90% of total body protein; the defensible point is that type I is the most abundant collagen type and dominates the collagen matrix in many connective tissues.

Key findings

  • Type I collagen is the most abundant collagen type and is prominent in skin, bone, tendon, cornea, fascia and organ capsules.
  • Twenty-eight collagen types were recognized in the literature reviewed.
  • Type I collagen is a fibrillar triple-helix protein built primarily from two α1(I) chains and one α2(I) chain in its common heterotrimeric form.
  • Commercial type I collagen can be sourced from marine, bovine, porcine and other animal tissues, with extraction and processing affecting material properties.
  • The review is a technical biology and biomaterials overview; it does not establish an oral-supplement dose or clinical efficacy.

What this study can and cannot tell us

  • Narrative review rather than a systematic review; it does not provide a PRISMA-style selection process or formal risk-of-bias assessment.
  • The review focuses primarily on literature from the preceding five years, so older foundational work is not comprehensively represented.
  • The article contains imprecise wording that type I collagen makes up '90% of the human body.' This should not be interpreted as 90% of total body protein; the reliable biological takeaway is that type I is the dominant collagen type in many connective tissues.
  • The applications section spans many domains at moderate depth and is not a substitute for dedicated clinical reviews of skin, joint or bone supplementation outcomes.
  • This paper does not directly test oral collagen supplementation or any clinical endpoint.

Related papers in the corpus

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Bone Broth Unlikely to Provide Reliable Concentrations of Collagen Precursors Compared With Supplemental Sources of Collagen Used in Collagen Research
Rebekah D. Alcock et al. · International Journal of Sport Nutrition and Exercise Metabolism · 2019
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Assessment of effectiveness of oral administration of collagen peptide on bone metabolism in growing and mature rats
Jian Wu et al. · Journal of Bone and Mineral Metabolism · 2004

Editorial review

Reviewed by the Biohack Blueprint research team

Last verified

Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction Dr. Amr Yasser, PhDCardiometabolic, Musculoskeletal, Gut & Bioavailability Dr. Abdulla Mostafa, PhDCellular Senescence, Neurological, Mitochondrial & Brain-Ageing Biology