What is Collagen?
[[File:Collagen_--_Smart-Servier_(cropped).jpg|thumb|right|300px|Collagen with triple helix (left) and microscopic structure (right).]] '''Collagen''' is a group of naturally occurring [[protein]]s. In nature, it is found exclusively in [[animal]]s, especially in the flesh and [[connective tissue]]s of [[mammals]].<ref>{{Cite journal |last=Müller |first=Werner E.G. |title=The origin of metazoan complexity: Porifera as integrated animals |journal=Integrated Computational Biology |volume=43 |issue=1 |pages=3–10 |year=2003 |doi=10.1093/icb/43.1.3 |pmid=21680404 }}</ref> Vitamin C is vital for collagen synthesis, while Vitamin E improves its production.<ref>{{Citation|title=Collagen|date=2025-01-31|url=https://en.wikipedia.org/wiki/Collagen|work=Wikipedia|language=en|access-date=2025-02-04}}</ref> It is the main component of connective tissue, and is the most abundant protein in mammals. It makes up about 25% to 35% of the whole-body protein content.<ref>{{Cite journal |first1=Gloria A. |last1=Di Lullo |first2=Shawn M. |last2=Sweeney |first3=Jarmo |last3=Körkkö |first4=Leena |last4=Ala-Kokko |name-list-style=amp |first5=James D. |last5=San Antonio |title=Mapping the ligand-binding sites and disease-associated mutations on the most abundant protein in the human, Type I Collagen |journal=Journal of Biological Chemistry |volume=277 |issue=6 |pages=4223–4231 |year=2002 |pmid=11704682 |doi=10.1074/jbc.M110709200 |doi-access=free }}</ref> Collagen, in the form of elongated fibrils, is mostly found in fibrous [[Tissue (biological)|tissues]] such as [[tendon]], [[ligament]] and [[skin]], and is also abundant in [[cornea]], [[cartilage]], [[bone]], [[blood vessel]]s, the [[gut]], and [[intervertebral disc]]s. Collagen makes up 1% to 2% of muscle tissue, and accounts for 6% of the weight of strong, tendinous muscles.<ref>{{Cite book |last=Sikorski |first=Zdzisław E. |year=2001 |title=Chemical and functional properties of food proteins |location=Boca Raton |publisher=CRC Press |page=242 |isbn=1566769604 }}</ref> [[Gelatin