What is collagen? Who should take it – and who shouldn't?

From skin and joints to sports recovery — an evidence-based guide to collagen, including key questions, food sources, and smart supplement choices.

Collagen has become one of the most talked-about supplements in recent years, often associated with glowing skin and anti-ageing benefits. But beyond the beauty industry, collagen is increasingly being recognised for its role in supporting joint health, recovery, and performance, particularly in active individuals and athletes.

In this blog, we’ll explore what collagen actually is, why it matters, and who might benefit most from supplementing.

What is collagen?

Collagen is the most abundant protein in the human body. Think of it as your body’s internal scaffolding, which provides structure, strength, and support to many key tissues, including:

• Tendons

• Ligaments

• Cartilage

• Skin

• Bones

Your body naturally produces collagen, particularly during childhood and early adulthood when growth and repair demands are high.

Why do we need collagen?

Collagen plays a central role in maintaining the integrity and function of connective tissues. It contributes to:

• Joint stability and cartilage resilience

• Bone strength

• Skin elasticity and hydration

• Wound healing and tissue repair

However, collagen production unfortunately doesn’t remain constant. From our mid-20s onwards, natural collagen production begins to decline. While this doesn’t usually require intervention early on, it can become more relevant from our 40s and beyond, particularly when combined with changes in activity levels, recovery, and joint health. Regardless of age, certain lifestyle factors can speed up collagen breakdown. These include:

• Smoking

• Excessive sun exposure

• Diets high in refined sugar

For active individuals, this decline in collagen can be particularly relevant. Repetitive loading through regular exercise, especially running or high-impact sports, places ongoing stress on tendons and ligaments, increasing the importance of effective tissue repair and recovery.

What the research says

The science behind collagen supplementation is still emerging, but early findings are encouraging. A growing body of research, including trials in athletes, active adults, and older populations, suggests that collagen peptide supplementation can support joint health, reduce exercise-related joint pain, and aid recovery from tendon and ligament injuries. Some studies have also explored collagen’s role in skin elasticity and bone density, with broadly positive results.

That said, much of the research uses relatively small sample sizes, and scientists are still working to establish optimal dosing, timing, and formulations. It is also worth noting that food-based sources of the nutrients that support collagen synthesis, such as protein, Vitamin C, Zinc, and Copper, remain the foundation of any good approach, with supplements best viewed as a targeted addition rather than a substitute.

How do we get collagen?

Your body makes collagen using amino acids, known as the building blocks of protein. This means that sufficient dietary protein intake on a regular basis is essential for collagen production. Key protein sources include poultry (chicken and turkey), fish and seafood, meat (pork, lamb, beef), tofu, eggs, beans and pulses, and dairy products.

However, protein alone isn’t enough. Vitamin C is essential for collagen synthesis. Without it, the body cannot effectively produce collagen, even if your protein intake is high. For this reason, it is essential to include a variety of foods in your diet. Good sources of Vitamin C include citrus fruits, berries, peppers, and leafy greens (including kale, spinach, and broccoli).

Other important nutrients for collagen production include:

• Zinc and Copper: these minerals support enzymes involved in collagen formation and can be found in nuts and seeds (e.g. almonds, walnuts, cashews, pumpkin seeds), wholegrains, and shellfish

• Antioxidants: orange vegetables (carrots, sweet potatoes, orange peppers), contain carotenoids that help protect skin collagen from breakdown

Certain foods, like bone broth and slow-cooked meats, naturally contain collagen or collagen-forming essential amino acids, including glycine and proline. These can be useful additions to a balanced diet, although their exact contribution to collagen levels in the body is still being researched.

Should you take a collagen supplement?

For most people, collagen supplements are not needed, but they can be useful in the right context.

A food-first approach should always be the foundation, regardless of age or health goals. If you’re eating sufficient protein and including a variety of fruits, vegetables, and whole foods in your daily diet, your body has what it needs to produce collagen naturally.

That said, supplementation may be worth considering if you recognise yourself in any of the following

You might benefit from collagen if you:

• Are regularly active (running or high-impact sport) and want to support joint and tendon health 

• Are recovering from an injury involving ligaments, tendons, or joints 

• Are over 40 and noticing changes in joint comfort, stiffness, or skin elasticity 

• Struggle to consistently meet your protein needs through diet alone 

You may not need collagen if you:

• Are under 40, generally healthy, and eating a well-balanced, protein-rich diet 

• Have no current joint issues or increased physical demands 

In these cases, focusing on overall nutrition, recovery, and training load will likely have a greater impact than adding a supplement.

Choosing a collagen supplement

If you’re considering supplementation, here are a few practical tips:

• Look for reputable brands with evidence-based claims

• Choose a format that suits you: although powders are often more cost-effective, capsules offer greater convenience

• Check the label for “hydrolysed collagen” or “collagen peptides”

Hydrolysed collagen has already been broken down into smaller peptides, making it easier to digest and absorb.

How to take collagen supplements effectively

Getting the most out of collagen supplementation comes down to a few simple principles. Timing may matter - some research suggests taking collagen 30–60 minutes before exercise, alongside foods rich in Vitamin C, could help direct amino acids towards tendon and ligament repair during the post-exercise recovery window. A typical daily dose ranges from 5-15g of collagen peptides, though starting at the lower end and adjusting based on response is a sensible approach. Pairing your supplement with a source of Vitamin C, such as a small glass of orange juice or a handful of berries, is an easy habit to build into your routine and may meaningfully improve effectiveness.

Who should avoid collagen supplements?

Collagen supplements are generally considered safe for most people, but there are some important exceptions:

• Fish or shellfish allergies: avoid marine-based collagen

• Pregnancy and breastfeeding: because of limited safety research, supplementation should only be considered with professional guidance

• Vegans and vegetarians: most collagen supplements are derived from animal (bovine) or marine sources, so sourcing should be checked carefully

Collagen in summary

Collagen is the most abundant protein in the human body and plays a vital role in keeping our joints, skin, bones, and connective tissues healthy. While the body produces it naturally, that production declines with age, making dietary and supplemental support increasingly worthwhile as we get older. A diet rich in protein, Vitamin C, Zinc, and Copper will go a long way towards supporting your body’s own collagen synthesis.

For those looking for an extra edge, particularly around exercise or recovery, a daily collagen peptide supplement is a practical, well-tolerated option backed by a growing evidence base. As always, if you have specific health concerns or are managing a condition, speaking with a Nutritional Therapist or GP before starting a new supplement is a sensible first step.