6 mins read

What is Collagen?

September 28, 2023

Reviewed by: Dr Thom Phillips

Female health

Woman applying hrt patch to her upper arm

Collagen is a protein that plays a vital role in our bodies. It provides structure and strength to our skin, bones, tendons, and muscles. In fact, collagen makes up about 30% of the proteins in our bodies.

What Does Collagen Do?

Collagen plays a crucial role in maintaining the structural integrity of various tissues. It provides strength and support to our skin, ensuring its elasticity and firmness. As we age, however, the production of collagen starts to slow, leading to the appearance of wrinkles and sagging skin that can make us feel less confident.

But collagen is not just limited to our skin. It is also a vital component of our tendons, which connect our muscles to our bones, and ligaments, which connect our bones to each other. 

Are There Different Types of Collagen?

Yes, there are actually several types of collagen in our bodies. There are ore than 25 types of collagen, but the most common types are type I, II, III, IV and V.

  • Type I makes up 90% of your body’s collagen. Type I is densely packed and used to provide structure to your skin, bones, tendons and ligaments.
  • Type II is found in elastic cartilage, providing joint support.
  • Type III is found in muscles, arteries and organs.
  • Type IV is found in the layers of your skin.
  • Type V is found in the cornea of your eyes, some layers of skin, hair and tissue of the placenta.

When it comes to our bones, type I collagen is essential. It forms the framework upon which minerals like calcium and phosphorus are deposited, giving our bones their strength and rigidity. Without sufficient type I collagen, our bones would be more prone to fractures and other structural issues.

Type II collagen is primarily found in our cartilage. Cartilage acts as a cushion between our bones, preventing them from rubbing against each other and causing damage. Type II collagen provides the necessary support and elasticity to ensure smooth joint movement and reduce the risk of joint pain and stiffness.

Type III collagen is particularly abundant in the walls of blood vessels, helping to maintain their strength and flexibility.

In our organs, type III collagen provides support and structure to ensure their proper functioning. It acts as a scaffold, allowing different cells and tissues to organise and function harmoniously. Without type III collagen, our organs would lack the necessary framework to carry out their specialised functions.

What Happens to my Collagen Levels as I Age?

As we age, the natural production of collagen decreases. This decline occurs due to a combination of genetic factors, hormonal changes, and environmental influences. The gradual decrease in collagen production affects not only our skin but also our joints and connective tissues.

By the age of 25, collagen levels in our bodies begin to decline, and by the time we reach our 40s or 50s, collagen production can decrease by as much as 30%. This reduction in collagen leads to visible signs of ageing, such as wrinkles, sagging skin, and joint stiffness. 

Sun exposure, smoking, and poor diet can further accelerate the decline in collagen levels.

Wrinkles and fine lines are some of the most visible signs of declining collagen levels. As collagen fibres become less abundant and weaker, our skin loses its firmness and elasticity, leading to the formation of wrinkles. The reduction in collagen can also result in the thinning of the dermis, making blood vessels more visible and giving the skin a translucent appearance.

Symptoms of Low Collagen Levels

Low collagen levels can manifest in various ways. One of the most noticeable signs is the appearance of fine lines and wrinkles. You may also experience joint pain or stiffness, as well as brittle nails and thinning hair. A loss of elasticity in the skin and increased fragility of blood vessels can occur due to low collagen levels.

If you notice any of these symptoms, it may be an indication that your collagen levels are lower than they should be, and it’s time to take action to restore and replenish your body’s collagen supply.

What Causes Low Collagen Levels?

There are several factors that can contribute to low collagen levels. Ageing is a major factor, as our bodies naturally produce less collagen as we get older. 

Lifestyle factors such as sun exposure, smoking, and poor nutrition can further accelerate the decline in collagen levels. UV radiation from the sun’s rays can damage the collagen fibres in our skin[1], leading to premature ageing and an increased risk of skin cancer. Smoking, on the other hand, reduces blood flow to the skin, depriving it of essential nutrients and oxygen needed for collagen production[2]

In addition, certain medical conditions, such as autoimmune diseases and genetic disorders, can affect collagen production. It’s important to be aware of the factors that can contribute to low collagen levels so that you can make changes to support and enhance collagen production in your body.

How Can I Increase My Collagen Levels?

While it’s not possible to completely stop the decline in collagen production, there are steps you can take to support and enhance collagen levels in your body. One of the most effective ways is to incorporate collagen-rich foods into your diet.

Foods such as bone broth, fish, lean meats, and leafy greens contain essential amino acids and nutrients that promote collagen synthesis. 

Another way to increase collagen levels is through lifestyle changes. Avoiding excessive sun exposure and quitting smoking can help to preserve and enhance collagen production in your body.

What are Collagen Peptides?

Collagen peptides are a popular form of collagen supplements. They are made by breaking down proteins from animal collagen into shorter chains of amino acids, making them easier for the body to absorb and utilise. Collagen peptides are typically flavourless and can be added to smoothies, soups, or even your morning coffee.

Do Collagen Supplements Work?

While there is no shortage of collagen supplements on the market, their efficacy is debated. Some studies have shown significant positive changes in skin hydration and elasticity[3][4], while others have improvements in people with knee osteoarthritis symptoms[5]. However, it’s worth noting that results may vary depending on individual factors such as age, overall health, and genetics.

While collagen supplements may help, it’s always best to get collagen from a healthy and balanced diet. 

How Much Collagen Do I Need Per Day?

There is no recommended daily intake of collagen, so how much you take depends on your individual needs and goals. Collagen supplement doses range from 1g to 20g depending on the form. Daily capsules tend to have lower doses, whereas powders and bars can have more. 

Keep in mind that collagen is not a quick fix, and it can take several weeks or even months to see noticeable results. Consistency is key when it comes to incorporating collagen into your daily routine.

Collagen is a type of protein, so as such there is no Recommended Daily Intake value, however, research has shown that doses ranging from 2.5 to 15 g daily are safe[6] and can be effective in promoting some of the beneficial changes discussed here. Collagen supplements are regularly used to ameliorate healing post injury, as well as supporting post exercise recovery and making your skin look younger[7].

Dr Thom Phillips

What Foods Are Good For Collagen?

Incorporating collagen-boosting foods into your diet is a great way to support your body’s natural collagen production. Some of the best foods for collagen include:

  • Bone broth: A rich source of collagen and other beneficial nutrients.
  • Fish: Salmon and other fatty fish are high in omega-3 fatty acids, which help promote collagen production.
  • Lean meats: Chicken and turkey are good sources of the amino acids needed for collagen synthesis.
  • Leafy greens: Spinach, kale, and other leafy greens provide antioxidants that aid in collagen production.
  • Berries: Blueberries, strawberries, and raspberries are packed with vitamin C, which is essential for collagen synthesis.

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This information has been medically reviewed by Dr Thom Phillips

Thom works in NHS general practice and has a decade of experience working in both male and female elite sport. He has a background in exercise physiology and has published research into fatigue biomarkers.

Dr Thom Phillips

Dr Thom Phillips

Head of Clinical Services