Collagen: What It Is, Why We Lose It and Why the Type Matters

Collagen is the most abundant protein in the human body, accounting for around 25–30% of total body protein. It provides structure, strength and support to our skin, bones, cartilage, tendons, ligaments, blood vessels and other connective tissues.

As we age, our ability to produce and maintain collagen gradually declines. This is one of the reasons changes in our skin, joints, bones and connective tissues become more noticeable over time.
For healthy ageing, collagen is therefore about much more than appearance.

Collagen is a structural protein made from amino acids, particularly glycine, proline and hydroxyproline. These amino acids form long protein chains that are organised into strong fibres and networks throughout the body.

There are at least 28 recognised types of collagen, although Types I, II and III are among the most important.

Type I is the most abundant collagen in the body. It is found extensively in skin, bones, tendons, ligaments and connective tissue and is particularly important for the structure and strength of the skin.

Type II is the predominant collagen found in cartilage and is therefore particularly relevant to cartilage and joint structure.

Type III is found alongside Type I, particularly in skin, muscles, blood vessels and other connective tissues.

So, when you see a collagen supplement on the shelf, it is worth remembering that collagen isn't one single ingredient. The source, collagen type, processing and peptide composition can all differ.

Collagen production doesn't suddenly stop at a particular birthday. It is a gradual process that begins during adulthood.

Research suggests that skin collagen decreases by approximately 1–1.5% per year from around the age of 30. Over several decades, these small annual changes can add up to a significant reduction in collagen and changes in the skin's structure.

For women, the decline can become particularly noticeable around menopause.
Oestrogen plays an important role in maintaining skin collagen, and the reduction in oestrogen during menopause is associated with a more rapid decline in skin collagen. Research has found that women can lose approximately 30% of their skin collagen during the first five years of menopause. This can contribute to skin becoming thinner, drier and less elastic, with fine lines, wrinkles and loss of firmness becoming more noticeable.

But remember, collagen isn't only about the skin. It is also a major structural component of bones, tendons, ligaments, cartilage and connective tissue, making collagen an important consideration as part of healthy ageing.

Ageing is only part of the story.
Our lifestyle and environment can also influence how quickly collagen is broken down and how effectively our body can produce and maintain it.

Sun exposure
If there is one environmental factor particularly important for skin collagen, it is UV exposure.
UVA and UVB radiation increase oxidative stress and activate enzymes known as matrix metalloproteinases (MMPs). These enzymes break down collagen in the skin. Repeated UV exposure can therefore increase collagen degradation while interfering with the skin's ability to produce new collagen.
This process is known as photoageing and is a major contributor to premature skin ageing.
For Australians, this is especially relevant. We may love our sunshine, but decades of cumulative UV exposure can take a toll on our skin's collagen.

Smoking
Smoking is another significant contributor to premature skin ageing.
Cigarette smoke increases oxidative stress and can interfere with collagen production. Research suggests smoking can reduce the synthesis of Type I and Type III collagen while increasing processes involved in collagen breakdown.
Over time, this can contribute to loss of elasticity, wrinkling and poorer skin quality.

Alcohol
Heavy or regular alcohol consumption can also contribute to premature skin ageing.
Alcohol can increase oxidative stress and inflammation and may negatively affect hydration and the skin barrier. It doesn't mean that an occasional glass of wine suddenly destroys your collagen, but regular heavy alcohol intake is a different story. As always, the overall pattern matters.

Poor nutrition and inadequate protein
Your body needs adequate protein and a range of nutrients to build and maintain collagen.
Collagen is a protein, so consistently inadequate protein intake may compromise the body's ability to maintain tissues and repair them effectively. Nutrients including vitamin C, zinc and copper also have important roles in collagen synthesis and connective tissue formation.
This is why collagen supplementation shouldn't be viewed as a replacement for a nutritious diet.

Chronic stress and poor sleep
Our tissues are continually undergoing repair and renewal, and this process is influenced by sleep, stress and overall metabolic health.
Chronic stress and inadequate sleep can contribute to oxidative stress, inflammation and impaired skin barrier recovery, potentially affecting the processes involved in maintaining healthy skin.

Sugar and glycation
Another factor worth understanding is glycation.
Glycation occurs when sugars react with proteins and form compounds called advanced glycation end-products, or AGEs. Collagen is particularly susceptible because it is a relatively long-lived structural protein. Glycation can create cross-links between collagen fibres, making them stiffer and less flexible.
This is another reminder that healthy ageing is not about one magic supplement. It is about creating the best possible environment for your body to maintain and repair its tissues.

This is where collagen supplements can become confusing.
You may see products described as marine collagen, bovine collagen, porcine collagen or chicken collagen, as well as references to Type I, Type II or Type III.
The source and collagen type are related, but they aren't exactly the same thing.

Marine or fish collagen
Marine collagen is generally extracted from fish skin, scales or bones and is predominantly Type I collagen.
Because Type I is the major collagen type in the skin, marine collagen is commonly used in products targeting skin health.

Bovine collagen
Bovine collagen comes from cows and may be sourced from hide, skin, bones or other connective tissues.
It generally contains predominantly Type I and Type III collagen, making it commonly used in products aimed at skin, connective tissue and general collagen support.

Porcine collagen
Porcine collagen comes from pigs and can also contain predominantly Type I and Type III collagen, depending on the source and manufacturing process.

Chicken collagen
Chicken collagen is particularly associated with Type II collagen, which is the predominant collagen type in cartilage.
This is why Type II collagen products are often positioned towards joint and cartilage support rather than primarily skin health.

It's important to remember that these are general classifications. The exact collagen composition can vary depending on the tissue source and manufacturing process.

This is where collagen supplementation becomes particularly interesting.
When you consume collagen, it doesn't simply travel intact from your digestive system to your skin.

The collagen is digested into amino acids and smaller peptides, which can then be absorbed. Some of these collagen peptides appear to have biological activity beyond simply supplying amino acids.
Research suggests that particular bioactive collagen peptides can influence cells involved in maintaining the extracellular matrix — the structural network that supports tissues such as skin.

And this is an important distinction: Not all collagen peptides are necessarily biologically identical.
Different collagen products can have different sources, molecular weights and peptide profiles. Therefore, evidence from one specific collagen ingredient cannot automatically be applied to every collagen supplement on the market.

This is one of the reasons the research behind VERISOL® is particularly interesting.

VERISOL® is a branded range of Bioactive Collagen Peptides (BCPs®) developed by GELITA.
It is not simply a generic collagen powder.

The collagen undergoes controlled processing to produce a defined profile of specific collagen peptides, and the ingredient itself has been investigated in human clinical trials, particularly for skin health.

The marine/fish-derived VERISOL® used in the clinical research is derived from Type I fish collagen and is processed into specific bioactive collagen peptides. That distinction is important. It would be too simplistic to say:
“Type I collagen improves skin.” The research is actually investigating a particular preparation of collagen peptides with a specific peptide profile.

This means we shouldn't automatically assume that a generic marine collagen powder will produce exactly the same results simply because it is also described as Type I collagen.

One of the interesting clinical studies investigated fish-derived VERISOL® at 5 g per day in women aged 50–75.
The randomised, placebo-controlled study included Asian and Caucasian women and followed them for eight weeks.

After four weeks, researchers found a significant improvement in skin elasticity in the women taking the fish-derived collagen peptides. After eight weeks, the improvement was more pronounced, and there was also a significant reduction in eye-wrinkle volume compared with placebo.

These are particularly interesting findings because the researchers were measuring objective changes in skin characteristics rather than simply asking participants whether they thought their skin looked better.
Together, these studies suggest that specific collagen peptides may support the skin's own collagen-producing processes.

This is an important point when comparing collagen supplements. You might see one product containing 10 g, another containing 15 g and another containing 2.5 or 5 g. It is tempting to assume that the product with the highest number must be the best. But more collagen isn't necessarily better.

What matters is not just the number of grams but what those grams actually contain.

The source, processing method, peptide profile, dose and clinical evidence all matter. Five grams of a clinically studied bioactive collagen peptide cannot necessarily be considered equivalent to five grams of an unspecified generic collagen powder.

This is why I would look beyond the front of the tub. Rather than asking only: “How many grams of collagen does it contain?”, ask: “What collagen peptides am I getting, and has that specific ingredient been clinically studied at this dose?”

Collagen supplementation isn't a substitute for the fundamentals of healthy ageing.
Adequate protein, a nutrient-dense diet, resistance exercise, quality sleep, stress management, avoiding smoking and sensible UV protection all remain important.

Think of collagen supplementation as one piece of the healthy-ageing puzzle, rather than a magic solution.
For skin in particular, protecting the collagen you already have is just as important as supporting new collagen production. Sun protection, not smoking, a nutritious diet and maintaining good overall health all matter.
But as our natural collagen production declines, supplementation with a specific, clinically researched collagen peptide may provide additional support.

Collagen is much more than a beauty ingredient. It is a fundamental structural protein that supports the skin, bones, cartilage, tendons, ligaments and connective tissues throughout the body. Our ability to produce collagen gradually declines as we age, with the decline becoming particularly significant for women around menopause. UV exposure, smoking, heavy alcohol consumption, poor nutrition, inadequate protein, chronic stress, poor sleep and glycation can further contribute to collagen damage and breakdown.

And when it comes to collagen supplements, not all collagen is created equal.
Different sources provide different collagen types, and different manufacturing processes produce different peptide profiles.

For skin-focused healthy ageing, marine VERISOL® provides specific bioactive peptides derived from Type I fish collagen and has been clinically studied in humans. Research using 5 g daily has demonstrated improvements in skin elasticity and reductions in wrinkle volume, that's what makes VERISOL® particularly interesting. It's not simply about buying a product labelled "collagen". It's about looking at the specific ingredient, the peptide profile, the dose and the evidence behind it.

Because when it comes to collagen, the biggest number on the label isn't necessarily the most important number.