Collagens are like the DNA of tissues. Different types of collagen combine in different amounts to form different structures. It is the basic building block of all connective tissues. It is found in almost all parenchymal tissues, forming the roof of that tissue and providing its stabilization. In some studies, it is said that there are different numbers of collagen fiber types (14 species, 24 species, 29 species). It forms tissue-specific proteins and glycoproteins by forming the extracellular matrix. Collagens have a triple helix structure. the difference between them is the frequency and order of connections.

Type 1 collagen: It is said to be stronger than even the same amount of steel. It is mostly found in bone (90%), dermis, tendon, ligament and cornea structures. It is the strongest collagen type. The fibers are arranged parallel to each other. It occurs during the remodeling phase of healing.

Type 2 collagen: Cartilage forms the nucleus pulposus structure. There is a weak bond structure. The amount of liquid is too elastic. The fibers are randomly arranged. The purpose is shock absorber.

Type 3 collagen: It has a reticulated structure. It is located on the outer surface of the organs and the organ wall.

Type 4 collagen: It is flexible and forms the basic membrane structure.

Type 5: It is found together with type 1 in the lung, bone, cornea.

* Collagen type 1,2,3,5,11 is in fibril structure and they are the best oriented types.
* The synthesis of these fibers occurs with growth factor stimulation.
* In vitamin C deficiency, collagen production and connective tissue formation slows down. iron, copper, zinc should be used.
* Collagen production continues until the age of 40.
* It makes up 25-35% of all body proteins.