Here are some key points about collagen. More detail and supporting information is in the main article.25-27
Protein makes up around 20% of the body's mass, and collagen makes up around 30% of the protein in the human body.
There are at least 16 types of collagen, but 80-90% of the collagen in the body consists of types I, II, and III.
Type I collagen fibrils are stronger than steel (gram for gram).
Collagen is most commonly found within the body in the skin, bones and connective tissues.
The word "collagen" is derived from the Greek "kolla," meaning glue.
Collagen gives the skin its strength and structure, and also plays a role in the replacement of dead skin cells.
Collagen production declines with age (as part of intrinsic aging), and is reduced by exposure to ultraviolet light and other environmental factors (extrinsic aging).
Collagen in medical products can be derived from human, bovine, porcine and ovine sources.
Collagen dressings attract new skin cells to wound sites.
Cosmetic products such as revitalizing lotions that claim to increase collagen levels are unlikely to do so, as collagen molecules are too large to be absorbed through the skin.
Collagen production can be stimulated through the use of laser therapy and the use of all-trans retinoic acid (a form of vitamin A).
Controllable factors that damage the production of collagen include sunlight, smoking and high sugar consumption.