Collagen: The Science Behind its Effectiveness in Supplements and Skincare
What is collagen?
Collagen is a protein that is highly abundant in the human body and plays a crucial role in providing structural support to various tissues. It is known for its fibrous and strong nature. Collagen is a major component of connective tissues, including those found in bones, skin, muscles, tendons, and cartilage. This protein helps these tissues maintain their strength, elasticity, and ability to withstand stretching. It essentially acts as a "glue" that holds the body's structural elements together.
The Role of Collagen in the Body and Skin Health
Collagen is the predominant protein in the human body, with a fibre-like structure that forms connective tissue. As the name suggests, this type of tissue links various body tissues and plays a crucial role in the composition of bones, skin, muscles, tendons, and cartilage. It provides strength and resilience to tissues, enabling them to endure stretching.
“It has been proven that daily consumption of hydrolysed collagen in different doses, from different sources can bring many benefits for the human body from relieving joint pain to improving skin health.”
Schematic representation of collagen's structure
As we age, our bodies gradually produce less collagen, and the production decreases more rapidly due to factors like excessive sun exposure, smoking, overconsumption of alcohol, insufficient sleep, and a lack of exercise. With the passage of time, collagen in the deep layers of the skin undergoes a transformation from a tightly organised network of fibres to an unstructured maze.
Environmental factors can harm collagen fibres, reducing their thickness and strength, ultimately leading to the development of wrinkles on the skin's surface.
Diagram showing the structure of healthy skin with the different layers: epidermis, dermis and adipose tissue. Collagen fibres and elastin are also represented in the illustration.
Collagen plays a vital role in the body, particularly in maintaining skin health and various other functions. Here's a closer look at the role of collagen in the body and its impact on skin health:
Structural Support: Collagen is a primary component of the extracellular matrix, which forms the framework for tissues and organs. It provides structural support to the skin, giving it strength and resilience.
Skin Elasticity: Collagen fibres in the skin help maintain its elasticity and firmness. This elasticity is what allows the skin to bounce back when stretched or pressed.
Early Signs of Ageing: Collagen aids in preventing the formation of wrinkles and fine lines by ensuring that the skin retains its suppleness.
Skin Regeneration: Collagen is essential for skin cell regeneration and turnover. It helps in the repair of damaged skin and contributes to the continuous renewal of skin cells.
Hydration: Collagen is involved in retaining skin moisture, which is critical for a healthy and youthful appearance. Adequately hydrated skin looks plumper and smoother.
Wound Healing: Collagen is crucial for wound healing as it forms a scaffold for new tissue growth. It can accelerate the healing process and reduce scarring.
Joint Health: Collagen is also a key component of cartilage, which cushions and protects the joints. This contributes to joint health and mobility.
Hair and Nails: Collagen is thought to promote healthy hair and nails, as these structures also contain collagen.
Absorption of Collagen: How it Works in the Digestive Tract
In terms of food, collagen occurs naturally only in animal-derived foods, such as meat and fish, which contain connective tissue. Nonetheless, both animal and plant-based foods contain elements, including protein (essential and non-essential amino acids), that contribute to collagen production within our bodies.
Collagen absorption in the digestive tract is a process that involves the breakdown of collagen proteins into smaller components (amino acids) that can be absorbed and utilised by the body. Here's an overview of how this process works:
Ingestion: Collagen can be consumed in various forms, such as collagen supplements, collagen-rich foods, or collagen-containing products like bone broth. When you ingest collagen, it enters your digestive system through your mouth and travels to your stomach.
Stomach Acid: In the stomach, collagen is exposed to stomach acid, which plays a role in the initial stages of protein digestion. Stomach acid begins to denature (unfold) the collagen protein, making it more accessible for further digestion.
Enzymatic Digestion: The majority of collagen digestion takes place in the small intestine. Here, specialised enzymes, such as pepsin and pancreatic proteases, break down the collagen protein into smaller peptides and amino acids. These enzymes cleave the long collagen chains into shorter chains, making it easier for the body to absorb them.
Absorption: Once collagen is broken down into peptides and amino acids, it can be absorbed through the walls of the small intestine and enter the bloodstream. These smaller collagen components are then transported to various parts of the body where they can be used for a range of functions, including supporting skin health, joint function, and other collagen-dependent processes.
It's important to note that the collagen you consume is broken down into its basic building blocks, which are amino acids, during digestion. These amino acids are not specific to the collagen you have ingested but are part of the pool of amino acids used by the body for various purposes. The body can use these amino acids to support collagen synthesis and other protein-related functions, but they are not directly reassembled into intact collagen structures.
The Link Between Collagen Supplements and Improved Skin Health
Despite its abundant presence in our bodies, collagen has gained popularity as a top-selling supplement believed to enhance hair, skin, and nails — the key components of the elusive fountain of youth. The idea of taking a supplement that is devoid of side effects and can potentially reverse signs of ageing is appealing to many.
Initially, collagen was introduced as an ingredient in skincare products like creams and serums. However, its efficacy as a topical application was questioned even by dermatologists, as collagen is not naturally present on the skin's surface but in deeper layers. Collagen fibres are too large to penetrate the outer layers of the skin, and research has not supported the idea that shorter collagen chains, known as peptides, are more successful in this regard.
Furthermore, as in the case of intestinal absorption, the body will seize the collagen and direct it where it is most needed. Unfortunately, the skin may be the last place collagen can be sent to.
Oral collagen supplements, available in the form of pills, powders, and specific foods, are believed to be more easily absorbed by the body and have witnessed a surge in popularity among consumers. They may be marketed as collagen peptides or hydrolysed collagen, which are broken-down forms of collagen with enhanced absorption.
Collagen supplements contain amino acids, the building blocks of proteins, and may also include additional nutrients relevant to skin and hair health, such as vitamin C, biotin, or zinc. However, there is no proof that collagen powders are more readily absorbed than
protein powders, both of which contain the same molecules that will have to be broken down into amino acids.
What Does the Research Say About Collagen Supplements?
Most of the research on collagen supplements focuses on joint and skin health. While human studies are limited, some randomised controlled trials have shown that collagen supplements can enhance skin elasticity. Other trials have indicated that these supplements can improve joint mobility and reduce joint pain, particularly in cases of osteoarthritis or among athletes. Collagen accounts for approximately 60% of cartilage, a firm tissue that surrounds and cushions bones during high-impact movements. A breakdown in collagen can lead to cartilage loss and joint issues.
However, it's essential to acknowledge potential conflicts of interest in this field, as most, if not all, of the research on collagen supplements is funded or partially funded by industries that could benefit from positive study results; or one or more of the study authors may have ties to these industries. This makes it challenging to ascertain the true effectiveness of collagen supplements and whether they justify their often significant cost.
One downside of collagen supplements is the uncertainty regarding their composition and whether they live up to the claims on the label. There are also concerns about the presence of heavy metals in collagen supplements. In the United States, the Food and Drug Administration does not evaluate the safety or effectiveness of supplements before they are sold to consumers.
“There has been little effort on identifying which collagen types are the most suitable for cosmetic purposes.”
Another potential drawback is that taking a collagen supplement might serve as an excuse to neglect healthy habits that can protect against the decline of collagen, such as obtaining sufficient sleep and quitting smoking.
That being said, the available research has not demonstrated negative side effects in individuals using collagen supplements. They may be beneficial if your protein intake is suboptimal.
Can You Consume Collagen?
Foods containing collagen, or foods that support collagen production, include fish, shellfish, meat, oranges, kiwis, bell peppers, eggs, and whole grains. There is insufficient research to prove that consuming collagen directly benefits skin or joint health. Again, when digested in the stomach, collagen is broken down into amino acids, which are then distributed throughout the body where they are needed most. Nevertheless, many foods that support collagen production are generally recommended as part of a healthy diet.
Foods Rich in Collagen
Some foods are rich in collagen, particularly tough cuts of meat that contain a lot of connective tissue, such as shanks, brisket, and shoulder meat (e.g., chuck steak). Collagen is also present in the bones and skin of fish.
Bone broth, a trendy food frequently found in the soup aisle, is promoted as a collagen-rich health food. The process involves simmering animal bones in water with a small amount of vinegar to dissolve the bone and release collagen and minerals. The resulting broth can be simmered for varying durations, typically ranging from 4 to 24 hours. However, the content of amino acids can vary from batch to batch depending on the type of bones used, the cooking time, and the level of processing, such as whether it is a packaged or canned version.
Gelatin is a form of collagen derived from boiling animal bones, cartilage, and skin for several hours and allowing the resulting liquid to cool and solidify. Gelatin is produced through the breakdown of these connective tissues. Collagen and its derivative, gelatin, are promoted in certain dietary plans, such as the paleo diet.
Foods to Enhance Collagen Production
Numerous high-protein foods are believed to support collagen production because they contain the amino acids necessary for collagen synthesis, including glycine, proline, and hydroxyproline. These foods include fish, poultry, meat, eggs, dairy products, legumes, and soy.
Collagen production also relies on essential nutrients like zinc, which can be found in shellfish, legumes, meats, nuts, seeds, and whole grains, as well as vitamin C, derived from citrus fruits, berries, leafy greens, bell peppers, and tomatoes.
Collagen in Skincare: Is it Effective in Reducing Wrinkles and Fine Lines?
Collagen is a popular ingredient in skincare products, often promoted for its potential to reduce wrinkles and fine lines. Here's an overview of its effectiveness in this regard:
Topical Application: Many skincare products, such as creams and serums, include collagen as an ingredient. The idea is that applying collagen topically can improve the appearance of the skin by providing it with the protein it needs for elasticity and firmness. However, there is debate among dermatologists about the effectiveness of topical collagen. The reason for this doubt is that collagen molecules are typically too large to penetrate the skin's outer layers effectively. As a result, collagen applied topically may not directly replace or increase the concentration of collagen in the deeper layers of the skin.
Research Findings: Scientific research on the effectiveness of topical collagen in reducing wrinkles and fine lines is limited and mixed. Some studies suggest that certain types of collagen-based skincare products may lead to improvements in skin elasticity and moisture. Still, the results can vary widely among individuals. Additionally, the majority of the research on these products is conducted or funded by the cosmetics industry, which raises questions about potential bias in the findings.
Collagen Supplements: Collagen supplements, taken orally, are another approach to improving skin health. While the body digests collagen into its constituent amino acids during the digestive process, some studies suggest that collagen supplements may positively impact skin health. These supplements may support collagen synthesis in the body and lead to improvements in skin elasticity and hydration. However, more research is needed to establish the long-term effectiveness and safety of collagen supplements.
Holistic Skin Care: It's important to remember that maintaining healthy skin involves more than just the application of collagen-based products. Factors such as sun protection, a balanced diet rich in vitamins and minerals, hydration, and a consistent skincare routine (with natural and organic products) play crucial roles in skin health. Lifestyle factors like avoiding excessive sun exposure, not smoking, and getting adequate sleep are also essential in reducing the development of wrinkles and fine lines.
While collagen is a significant component of skin and is associated with its elasticity and firmness, the effectiveness of using collagen in skincare products to reduce wrinkles and fine lines is still a subject of ongoing debate and research.
“There is a divergence in the literature regarding the doses used, as well as the time of supplementation, which shows a lack of standardization in order to define what would be the best dosage and for how long the type 1 hydrolyzed collagen supplementation would be necessary.”
The impact of topical collagen products and oral collagen supplements may vary among individuals, and results may not be as dramatic as some marketing claims suggest. To be fair, applying collagen-containing cream, oil or lotion, is better than applying nothing at all. It won’t, however, make up for a bad diet and dehydration, too much stress and too little sleep.
“Recently, synthetic biology platforms are getting wide attention for the production of non-native collagen alternatives to meet the rising demand for collagen worldwide.”
This means, as always, when man is implicated, we never know what we will gain and the effect on our health. The manufacture of synthetic collagen is simply a tool to produce a cheaper produce. We can expect that the body won’t be able to recognise it and utilise it, as it is often the case in manmade substances.
This also means that we will have to be even more diligent when looking for collagen healthy and natural products. Perhaps, there won’t be a reason to choose collagen supplements. A regular or even raw vegan protein powder will offer more promising results without the side effects and the myriad of substances that will come with synthetic collagen, such as heavy metals, contaminants, additives, preservatives, and various other toxins that the human body has never been exposed to.
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