In cosmetic products and dietary supplements, ingredients such as hyaluronic acid or collagen are among the most important anti-aging substances. Collagen is a structural protein that, like hyaluronic acid, is found in the human body and makes up a large proportion of the supporting and connective tissue, but is reduced in the body’s own production with increasing age. The actual function of the protein has been exploited by science and research. As a manufactured substance for ingestion and application in powders, creams or capsules, collagen provides skin tightening and rejuvenation and stabilization of bones and joints.
Collagen – definition and occurrence in the human body
Of all the proteins in the human body, collagen is the most abundant protein and thus an existential component of connective tissue and skin. It ensures the stability of bones, muscles, tendons and teeth, healthy hair and strong nails, and supports blood vessels and organs.
Protein consists of individual long molecules that form a protein chain into a left-handed helix and, in each of three arrangements, into a right-handed superhelix. Hydrogen bonds are used for stabilization, while every third amino acid contained is glycine.
In addition, there are two other amino acids that complement glycine, and occur as proline and hydroxyproline. The function of the structural protein depends on its composition. In tissues and cells, collagen forms an extracellular matrix that is structured like a scaffold. In the skin, the protein provides more elasticity.
Collagen formation and production in the body
Collagen is largely produced by fibroblasts, which are connective tissue cells. They provide the extracellular structure, while collagen production involves the formation of long strands containing more than a thousand amino acids, called alpha chains or polypeptides. The fact that there are different types of collagen depends on the composition and arrangement of amino acids. Most collagens as an alpha chain are intertwined into a triple helix, called a triple helix or tropocollagen unit, which uses hydrogen bonds and glycine to strengthen its structure.
The fibrils or collagen fibers formed from linked tropocollagen units are extremely strong and stable. This can be seen in the production of gelatin, which is made from boiled collagen and water and heat cause the three alpha chains to dissolve. When the liquid cools, it forms a jelly-like substance.
Collagen can also be produced by breaking down acids and bases. The process of production and the origin of collagen accordingly play a significant role in the quality and effect in supplements. If the dissolved protein of gelatin is further broken down by water and enzymes, hydrolyzed collagen is formed, which in turn dries as a liquid substance and thus becomes collagen hydrolysate, which is contained in many dietary supplements and cosmetic products.
Natural breakdown of collagen in the body
The older a person gets, the more the natural production of collagen in the body decreases. There is a slowdown from the age of 25. The skin loses its tone and elasticity, and other areas of the body, in which the protein plays an important role, also undergo changing processes, such as the stability of joints and bones. Scientists assume that with increasing age about 1 percent of the structural protein is produced less per year. Therefore, it is worthwhile to compensate for the deficit at an early stage.
The decreasing collagen content causes the skin to wrinkle and dry out more quickly as it loses tone and firmness. The process is influenced by various factors, depends on genes, estrogen level and external influences, here above all UV radiation, environmental influences, a poor diet, stress or nicotine.
At the same time, the number of fibroblasts in the skin decreases, which additionally slows down collagen production. Chronic diseases or a vitamin deficiency also have an effect, especially if vitamin C, which promotes collagen formation, is lacking. With age, skin and hair become thinner, bones more unstable and tendons less flexible. This leads to joint and skin problems in many people.
The function of collagen in skin and joints
Collagen is structure-forming and water-binding. Above all, it has a supporting and stabilizing function in the body. This depends on the type of collagen. Together with elastin fibers, collagen proteins form the firm meshwork of the middle layer of the skin. Due to its ability to store water, collagen has a plumping effect from the lower to the outer layer of the skin, which is thus smooth and taut. In addition, collagen protects against inflammation and injury.
In bones, joints, tendons and ligaments, collagen proteins have the function of supporting repair processes and also serve to protect against injury. Collagens provide tensile strength and cushion the impact of bone movement. In joints, they are a natural cushion, so collagen proteins promote health and keep the body fit.
The different types of collagen
There are a total of 28 types of collagen found in the human body. The most important are collagen types 1 to 3. The types are formed by different cells, such as the connective tissue cells or fibroblasts already mentioned and cells of the bone tissue called osteoblasts. Both produce collagen types 1 and 3. Cells of the cartilage tissue, in turn, called chondrocytes, make collagen type 2.
Collagen type 1
Collagen type 1, formed from fibroblasts, is relatively broad and is found in the skin, connective tissue, cornea, muscle fascia, ligaments and tendons. Here it binds and stores water and provides elasticity and strength. The skin forms fewer wrinkles, the bones, ligaments and tendons are stable and protected.
Collagen type 2
Collagen type 2 is somewhat thinner and is found in greater amounts in cartilage tissue, in the vitreous humour of the eye and in intervertebral discs. It works excellently together with the body’s own hyaluronic acid. Its function is stabilization with high elasticity and compressive strength of all mentioned areas.
Collagen type 3
In skin and cornea and in internal organs, collagen type 3 provides more flexibility. It is a component of the granulation tissue and is contained in the reticular fibers, and also stabilizes the vascular walls.
Differences in the quality and production of collagen
In the fields of nutrition and cosmetics, collagen is used as a health and anti-aging substance. Collagen used for these purposes is usually extracted from bovine or porcine skin, thus maintaining the flexibility and elasticity of the skin. Other collagens come as raw material from fish. The release of collagen peptides from the molecular bond is achieved by the extraction process in the form of enzymatic hydrolysis.
Food supplements often contain collagen as gelatin, which is biochemically broken down by bases, acid or heat. Collagen hydrolysate differs from this because it is enzymatically hydrolyzed collagen that is water soluble but emulsion stabilizing. Another name for this is collagen peptides, which in turn are the end product of the hydrolysis process. Here, enzymes are used to break down and dissolve the peptide bonds so that they can then be extracted.
A supplementary supply of collagen counteracts the progressive physical degradation and therefore has a proven positive effect on the aging process of the skin and on the stability of bones and joints. Qualitatively, there are differences that depend on the collagen extraction itself. For example, vegetable collagens are of no significant benefit, as they consist of the thickening agent of polysaccharides and thus have no effect on the skin. Therefore, only animal collagen from bovine or porcine skin or marine collagen from fish, which act like the body’s own collagen types 1, 2 and 3, serve as a decisive anti-aging molecule.
The effect of collagen ingestion and use.
For anti-aging and dietary supplements, collagen hydrolysate or collagen peptide is used above all services. Legally, it is a food as a special form that is hydrolyzed enzymatically. In dietary supplements, collagen hydrolysate provides high protein content and is not associated with any allergy risk. In addition, it is said to enable better nutrient supply in bones and joints or reconstruction of damaged tissues.
The effect of collagen peptides in dietary supplements such as “D3 Vega D3” already unfolds through oral intake and enables the build-up, maintenance and regeneration of cartilage tissue and skin. Studies, such as the Gold Standard Study, have shown that collagen hydrolysate is excellent for therapy and prevention in joint and cartilage wear and tear, and also relieves pain and improves mobility. This is also shown by other studies at the University of Kiel or Giessen, which were able to prove that administration of collagen hydrolysate promotes the formation of new cartilage.
In a long-term study, short-chain collagen peptides in particular proved to be promising due to their high bioavailability and bioactivity, e.g. in the study by McAlindon. The short-chain collagen peptides stimulate skin regeneration and ensure healthy and elastic skin. Even collagens taken in liquid form achieve a short-term effect due to their high bioavailability, as they also reach the deeper layers of the skin.
Clinical studies, such as those by Hunter or Henrotin, have consistently concluded that collagen hydrolysate reduces the depth of wrinkles in the skin and has a positive effect on skin elasticity, skin regeneration and the moisture content of the skin. The skin texture is visibly and sustainably refined and improved.
Other studies also produced excellent results. In 2014, the Proksch study with test subjects over the period of 8 weeks and a daily intake of 2.5 collagen peptides showed the reduction of wrinkle depth around the eyes of about 18 percent with the simultaneous refinement of the skin appearance.
The situation is similar with cellulite. In the 2015 study by Schunck, there was a reduction in skin rippling in normal weight and overweight women when they took 2.5 grams of collagen over a 6-month period.
Studies by Asserin in 2015 and by Kim in 2018 provided evidence of improved skin hydration, and taking a drinking collagen supplement for a 90-day period with 5 grams of collagen peptides in the 2017 study by Genovese resulted in significantly improved skin elasticity. Bioactive collagen hydrolysate is therefore indispensable in cosmetic and health products, and in high-quality production offers the following benefits at a glance:
Bone and joint health
Reduction of inflammation and cartilage degradation
Improvement of skin elasticity and appearance
Support of hyaluronic acid production
Increasing the moisture content of the skin
Promotion of repair processes in the body
Reduction of wrinkle depth
Improvement of hair structure
Reduction of cellulite
Support in muscle building
The interplay between collagen and other vital substances
For the body to form collagen, it needs amino acids and vitamin C. The latter serves as a co-factor of enzymes, which in turn influence energy requirements, body temperature and biochemical reactions in the organism. Vitamin C, as the most important health vitamin, ensures the incorporation of the amino acid hydroxyproline into the triple helix of collagen.
In addition to vitamin C, which serves to protect skin cells, cosmetics and dietary supplements often contain other supporting vital substances. For example, collagen and hyaluronic acid combine excellently to promote greater moisture retention and skin elasticity. In anti-aging preparations, vitamins, secondary plant substances and minerals basically serve as supplements, such as vitamin A or retinol, vitamin B2, zinc, copper, riboflavin, iodine, biotin and niacin.
Collagen can be taken in creams, serums, in drinking ampoules, powders, capsules and tablets. It turns out that taking collagen in oral form has a much better effect than applying it to the skin through creams and gels. The reason for this is the stimulation of internal physical processes and the ability to reach deeper layers of the skin, whereas collagen applied externally only penetrates the upper layers of the skin and does not remain in the skin long enough. Accordingly, the effect is limited in time, while the use of collagen preparations has a lasting effect. The aging process of the cells and the skin is slowed down by stimulating collagen formation and improving the elasticity of the skin.
