Collagen is a protein that plays a crucial role in maintaining the shape and structure of tissues and organs in the body. It is the most abundant protein in mammals and is responsible for the strength, elasticity, and support of various body parts such as skin, bones, tendons, ligaments, and joints. In recent years, collagen has drawn a lot of attention as a dietary supplement. Today we look at the different types of collagen, what they do in the body and what has been studied about them.
Understanding Collagen: The Body's Building Block
What is Collagen? – Structure, Stability and Amino Acids
Collagen is a highly complex structural protein and makes up about one-third of our total body protein. It consists of amino acids such as glycine, proline, arginine, and hydroxyproline, which combine to form a characteristic triple helix. This helix gives collagen its crucial strength and stability, as glycine creates space in the center while hydroxyproline and proline stabilize the helix.
Collagen Family: 28 Types with Clear Order
The collagen family comprises a total of 28 types, numbered with Roman numerals. Each type fulfills specific functions in certain tissues. Particularly relevant for you are the three main types – Type I, II, and III – which make up the majority of our collagen:
- Type I, by far the most common type, is found in skin, bones, tendons and ligaments and gives them structure and elasticity.
- Type II is the central component of cartilage tissue, which cushions impact in the joints.
- Type III is frequently found together with type I in skin, vessels and organs, where it is part of the elastic tissue.
Type I Collagen: Skin, Tendons and Bone
Where type I occurs
Type I collagen is the most common structural protein in the human body and occurs above all in skin, tendons, bone, ligaments and other connective tissue. There it makes up the bulk of the collagen fibres.
What has been studied
Hydrolysed type I collagen, also called collagen peptides, is among the most frequently studied forms, with studies typically running over eight to twelve weeks. Such studies usually measure skin moisture, elasticity and wrinkle depth and compare them with a control group that does not receive the supplement. This shows which changes would have happened without it anyway.
Type II Collagen: The Collagen Type of Cartilage
Where type II occurs
Type II collagen is the main component of articular cartilage. It is also found in the airways, the nose and the ribs, where it contributes to the structure of cartilage tissue.
What has been studied
In a randomised, double-blind study, a daily dose of 40 mg of undenatured type II collagen (UC-II) was compared with glucosamine and chondroitin. A pilot project examined 3.2 mg of UC-II over twelve weeks in healthy participants. Further work comes from animal models and is not directly transferable to humans.
The order of magnitude is striking: UC-II is dosed in milligrams, hydrolysed collagen peptides in grams — two separate approaches that cannot be set against each other.
Type III Collagen: Type I's Partner in the Skin
Where type III occurs
Type III collagen occurs together with type I in skin, ligaments, blood vessels and joints. Its share declines with age, and the skin becomes thinner and less elastic.
What has been studied
In one clinical study, injectable type III collagen fibres were applied into the dermis and wrinkle depth was recorded after 90 days. That application has nothing to do with taking collagen by mouth and cannot be transferred to supplementation. Oral studies with hydrolysed collagen, by contrast, record elasticity and skin structure over controlled periods.
The difference between injection and oral intake is frequently overlooked in public discussion.
Choosing the Right Collagen Product for Your Needs
If you are considering a collagen product, it is worth looking first at the format and the source. There are powders, capsules and liquids from various sources such as marine, bovine or porcine collagen.
Which types are studied for what
Types I and III are the most common collagen types in skin, tendons and ligaments; hydrolysed peptides from them are studied in gram quantities. Type II is the collagen type of cartilage; native, undenatured type II (UC-II) is researched in milligram quantities and by way of the oral tolerance mechanism. The two approaches are not interchangeable, and neither is broadly superior to the other.
Many manufacturers combine several types in one product. That covers a wider range of tissues, without any statement about effect following from it.
What to look for when buying
Check whether the product is hydrolysed, that is, broken down into peptides. Also make sure your diet gives you enough vitamin C: vitamin C contributes to normal collagen formation for the normal function of skin, bones and cartilage. Marks such as GMP or third-party laboratory testing say something about manufacturing and purity.
Quantities commonly used in studies
Studies with hydrolysed collagen typically use 2.5 to 10 grams a day. For UC-II it is 40 mg. Marine collagen is often studied because of its peptide size, while bovine and porcine collagen are usually cheaper to produce.
Which format suits you depends above all on what you can reliably take day to day.
Incorporating Collagen into Your Daily Routine
Collagen supplements are only one way of bringing collagen into your day. A nutrient-rich diet that is rich in proteins, vitamins, and minerals can provide the necessary building blocks for collagen synthesis. Foods like bone broth, lean meat, fish, eggs, dairy products, fruit and vegetables supply these nutrients.
Also, a lifestyle that promotes general health and well-being can contribute to collagen maintenance. Regular exercise, adequate sleep, stress management, and avoiding excessive sun exposure can help maintain collagen levels and promote healthy skin and joint function.
Don't forget: no supplement replaces a balanced lifestyle. Good nutrition, physical activity and self-care are the foundation.
Conclusion
Collagen is a structural protein that occurs in skin, tendons, bone, cartilage and connective tissue.
The types differ mainly in which tissue they predominate in: type I in skin and bone, type II in cartilage, type III alongside type I in the skin.
Knowing those differences makes product information easier to place — for instance with the multi collagen products, which combine several types in one preparation.
The research on hydrolysed peptides and the research on native type II are two separate strands and cannot be set against each other.
Speak to your doctor before taking a new supplement, to make sure it fits your individual needs and goals.
Image credits: Valeria Smirnova, Towfiqu barbhuiya, Angélica Echeverry, Marcel Strauß, Krisztian Tabori, Jexo on Unsplash