Collagen is a so-called structural protein. In addition to creatine and elastin, collagen is one of the most important structural proteins in our bodies.
These are proteins that do not serve as enzymes but have a supporting function for cells and tissues. They make sure they are elastic and firm, giving them shape and tension.
Its main functions are:
- Establish the elasticity of the skin.
- Ties and ligaments hold joints and bones together.
- Ensure a firm cartilage structure, eg articular cartilage.
- Formation of the structure of bones, vessels, teeth, and organs.
Collagen is formed from collagen molecules that combine to form long protein chains, forming a helix. Of these, three always combine to form a so-called superhelix, which is stabilized by hydrogen molecules.
This superhelix is also known as a fibril. The collagen fibers are screwed tight together, which is responsible for their enormous strength. Neighboring collagen molecules are staggered, so that dense and less dense area is formed.
This set of fibrils is called collagen fiber. These fibers can group water together, creating a large part of its weight.
Collagen is an essential part of many body structures. After all, with almost 30% it makes up the majority of all protein in our bodies. Therefore, it takes on a variety of important functions in the body.
The skin is the bigger organ of the body. It has a protective function and takes on many different tasks:
- Protection against temperatures.
- Protection against pressure, friction, and shock.
- Prevent pathogens from entering through the protective acid mantle.
- Protection against chemical radiation and damage.
- Prevent heat and moisture loss.
- Information registration as a sensory organ.
In order to fulfill all these tasks, the skin has a very special structure. The top layer of skin, also called the epidermis, consists of 5 different layers. Beneath is the dermis, which consists of loose connective tissue and is elastic.
The dermis is made up of two layers, the papillary dermis or thin top layer, which is formed from a dense network of collagen fibers and is filled with elastic tissue. This gives the skin its firmness, elasticity, and tension.
And the reticular dermis or thick bottom layer below it. In this, the fat pads are embedded in the loose tissue and some runners from the dermis pass through them.
The so-called body fascia, which also consists of collagen fibers, is located directly under the skin.
2. Connective tissue
Connective tissue is an important tissue for the body, consisting of cells and intercellular substances. Some connective tissue cells are mobile, while others are firm.
Both are embedded in an extracellular matrix, which is formed primarily from collagen and other structural proteins. From these, a network is formed, where the so-called proteoglycans settle in the interstices.
Collagen fibers make the structure more resistant to tensile forces. The proteoglycans regulate compressive forces. By combining these two abilities, the connective tissue maintains the shape of the organs, among other things.
Connective tissue weakness can have several effects. If, for example, the skin surface is no longer adequately supported, dents form on the skin.
These are generally known as orange peel or cellulite and are generally found on the thighs or buttocks. The striations are also a sign of weak connective tissue.
Here, the tissue is injured due to overstretching. The stripes are bluish in color at first but then become lighter and fade over time. Also, a weak connective tissue in the legs can cause a broom tear or varicose veins.
The human skeleton consists of more than 200 different bones. These have a support and protection function in the body and have a very stable structure. Without the skeleton, for example, humans would not be able to walk upright.
The bone structure will be divided into two layers, the outer layer of cortex (compact or cortical bone) and the inner cancellous structure (cancellous or trabecular bone). The bone tissue ensures the stability of the bone.
Bone cells (osteocytes) are embedded in an extracellular matrix. Most of the organic components in this matrix consist of collagens, in particular, type 1.
The crystals of the mineral hydroxyapatite bind to the collagen fibrils formed from them in a special arrangement. This combination of collagen and minerals ensures firm and healthy bones.
A joint is a flexible connection between two or more bones. There are a total of 360 joints in the human body, the largest being the hip and knee joints.
A joint is made up of two specially shaped bones that mesh perfectly. One bone is called the joint head and the other end is called the joint cavity. The entire joint is surrounded by a protective sheath, also called a joint capsule.
It is made up of ligaments, tendons, and muscles. Both ends of the bone are covered by a thin layer of cartilage and are separated from each other by the so-called joint cavity. It contains the so-called synovial fluid.
The cartilage layer and synovial fluid ensure smooth, painless movement in the joint. If one of the two factors is damaged, the movements in the joint can often become painful.
Cartilage consists of cells (chondrocytes) and an extracellular matrix, the basic substance of which contains networked collagen fibers. Therefore, the loss of collagen can also cause a loss of cartilage mass.
5. Blood vessels
Blood vessels supply the human body with oxygen and nutrients. They also transport blood back to the heart so that it can absorb new oxygen. It is particularly important that the blood vessels are elastic to ensure optimal care and to compensate for fluctuations in blood pressure.
The two proteins collagen and elastin are responsible for making blood vessels elastic and at the same time stable. With increasing age or certain diseases such as diabetes mellitus, the elasticity of the blood vessels may decrease and this can lead to calcification of the vessels.
Types of collagen
There are different types of collagen. Today a total of 28 are known, with type 1 being the most common in humans, which is why it is often used as a synonym for protein. There are also at least 10 other proteins that have a collagen-like structure.
- Collagen I (fiber former in collagen fibers): skin, tendons, bones, dentin, fiber cartilage, cornea.
- Collagen II (fiber former): hyaline cartilage, fibrous cartilage, elastic cartilage, vitreous.
- Collagen III (fiber former in reticulin fibers): skin, skeletal muscles, blood vessels.
- Collagen IV (reticular): basal lamina (especially dense lamina).
- Collagen V (fiber former): fetal tissue, placenta, interstitial connective tissue.
- Collagen VI (fiber-associated, spherical): connective tissue.
- Collagen VII (anchor fibrils): anchor epithelia in the basement membrane and stroma.
- Collagen VIII (reticular): Descemet’s membrane.
- Collagen IX (associated with fiber): cartilage, vitreous body.
- Collagen X (reticular): growth zone of cartilage.
- Collagen XI (fiber former): cartilage.
- Collagen XII (associated with fiber): embryonic skin, embryonic tendons.
- Collagen XIII: bones, cartilage, skin, striated muscles.
- Collagen XIV: especially in the intraneural connective tissue of the nerves, in the epi and the perimysium, also inside the muscle after denervation.
- Collagen XV: basement membrane of the muscles, in the kidneys after fibrosis.
- Collagen XVI: in the internal organs, in the eyes, and something in the muscular tissue.
- Collagen XVII (transmembrane): association with squamous cell hemidesmosomes of the epidermis.
- Collagen XVIII: unknown.
- Collagen XIX: (associated with fiber): fetal skin, fetal tendons.
This type of protein is called fibrillar collagen. This means that the protein can produce fibrils, which are very fine muscle or nerve fibers. Also, this type is mainly found in the following structures:
- Cornea and dermis of the eye
As with type 1, this is also a fiber-forming protein. It can be found in various types of cartilage, as well as in the vitreous of the eye.
Type 1 and type 3 are often associated with each other, as both have a fiber-forming function and therefore belong to fibrillar collagens. This one is particularly important for reticular fibers and therefore also for the reticular system.
These fibers are very fine strands that are arranged like a network. The tissue is found mainly in the lymphatic organs such as the lymph nodes, the spleen, or the tonsils. In addition, type 3 is also found in other body structures:
This type of collagen also has a crosslinked structure. It is mainly found in the basement membrane. This separates the epithelial tissue from the body to the connective tissue underneath, for example in the case of fats and muscle fibers.
This type is also a protein associated with fiber. It can be found mainly in the extracellular matrix of skeletal muscle. Protein is also found in bone and cartilage tissue, tendons, skin, as well as fatty and nervous tissue.
Other types of collagen
The rest of the types of collagen in the human body also have a function of fiber formation, reticular, or transmembrane. For example, they are part of the placenta or fetal tissue.
But they can also be found in the internal organs, skin, eyes, or growth areas of cartilage. However, the exact function of many species has not yet been clarified and is still being investigated.
Collagen hydrolyzate or collagen peptides
Both terms are the same form of collagen. This is often found in food supplements like collagen powder.
Similar to gelatin, collagen hydrolyzate is obtained from protein. However, it is modified using enzymes to make it soluble in water. This increases its bioavailability and the body can absorb it more easily.
The amount of collagen the body really needs is still not exactly clear. Generally speaking, the body is able to produce the protein from amino acids and thus satisfy the body’s own needs.
However, this need varies from person to person. Therefore, a person with joint or cartilage problems will have a greater need than a fit and healthy person. Furthermore, production decreases with age, so its demand increases.
In general, animal studies also showed no side effects at a high dose. Doses of 5000 milligrams per kilogram of body weight also showed no toxic effects, so use is considered relatively safe. However, side effects can occur in rare cases:
Foods for the formation of collagen
Vitamin E inhibits the activity of enzymes that break down the protein. By inhibiting collagenases, a breakdown is counteracted, which means that more collagen is available. Vitamin C is not only an important component in the elimination of free radicals, but it also plays an important role in the production of collagen.
It is an important co-factor of enzymes involved in the formation of the structural protein. It also activates collagenase antagonists and therefore counteracts decomposition in a similar way to vitamin E.
This is the reason why foods rich in vitamin E and vitamin C play an important role in the production of collagen.
These include, for example:
- Sea buckthorn
- Paprika or paprika
- Superfoods like acai
- Cabbage types such as kale or Brussels sprouts
- Citrus fruits like oranges, lemons, and grapefruits
- Vegetable oil
In addition, silicon also participates in the formation of collagen. It is important for the formation of connective tissue fibers in the skin and other tissues. It has a supporting role for the enzyme prolyl hydroxylase (PHD), which is a large part of collagens synthesis. Foods that contain a lot of silicon are, for example:
Vitamin C is an essential part of collagen formation. It acts as a cofactor of the enzymes involved. This is why it is very important for the production of solid and stable collagen fibers.
A study of skin fibroblasts was able to demonstrate that type 1 and type 4 synthesis could be significantly improved by long-term administration of vitamin C for 5 days.
For this reason, many dietary supplements like collagen powder also contain vitamin C to promote the absorption and utilization of collagen.
Collagen as a dietary supplement
There are various forms of protein as a dietary supplement. It can be taken as collagen powder and as a tablet or capsule. Each shape has its advantages. Powdered collagen can be easily dissolved in water and is odorless and tasteless.
Therefore, the body can easily absorb it. Tablets or capsules are of course ideal for traveling as they are easy to transport.
The collagen hydrolyzate is contained in all forms since bioavailability is greater here. When buying a dietary supplement, you should pay close attention to the type it contains.
Type 1 and Type 2 agents must be available. Therefore, the intended use must be thought of beforehand. Type 1 mainly benefits the skin and bones, while type 2 is particularly important for cartilage. However, this separation should not be seen too strictly because both types also appear mixed in the body.
Collagen and hyaluronic acid are often compared, and many wonders which substance is really more important to the skin. However, there is no answer to this, as both are essential to the skin’s structure.
Both ensure that the skin remains firm, moist, and elastic. If one of the two substances is missing, the skin becomes dry and brittle and wrinkles form. All this can also have an effect on the immune system since the skin protects against a large part of external influences.
If this weakens, viruses and bacteria have an easier time penetrating the body and nesting there. That is why many nutritional supplements like collagen powder are also fortified with hyaluronic acid to cover this area as well.