What is collagen?

The beauty and wellness world is constantly evolving with new trends and ingredients, but few have gained as much attention recently as collagen.

Collagen has certainly become one of the biggest buzzwords in the world of beauty and wellness, and it seems like everyone is trying to consume more, including our own Mumsnet users. But what is collagen and why is it so good for us?

“Collagen is definitely having its wellness moment – much like coconut oil, turmeric lattes, or whichever supplement happens to be trending. It is important, but let’s not get swept up in the hype. A healthy, balanced diet will always be the foundation,” says Carla Pozner, Osteopath and Wellness Expert.

Dr Daniel Atkinson, Clinical Lead at Treated.com. adds: “The evidence that collagen can improve hair, skin, nails and joints is limited. Collagen production naturally slows down with age, so supplements are designed to make up for this decline, and are purported to help fix a wide range of physical issues or improve their appearance and condition. As with all supplements, it’s worth managing your expectations as there’s no guarantee they’ll do what they claim to.”

Understanding what collagen is and how it works can help you make informed decisions about your health and beauty routine.

What is collagen?

Collagen is our body’s main protein. It’s the main building block for the body’s skin, muscles, bones, tendons, ligaments and other connective tissues. It can be found in your organs, blood vessels and intestinal lining. 

“It’s helpful to emphasise that collagen is not just about plump skin. It’s a structural protein — think scaffolding — for joints, tendons, ligaments, and connective tissues. As an osteopath, I see how vital that musculoskeletal support is for posture, movement and overall resilience,” explains Pozner.

Why collagen matters as you age

After the age of 25 years old, our resources of collagen decrease by 1 to 2% annually, leading to visible signs of ageing like wrinkles and weakened hair and nails. By 40, we may lose up to a third of our natural collagen, with a steeper decline during peri-menopause.

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“Women often notice changes around perimenopause — not just in skin elasticity but also in muscle strength and joint comfort. That’s why protein intake, strength work, and lifestyle habits become so important in your 40s and beyond,” says Pozner.

Beyond its beauty benefits, it’s also involved in essential roles like supporting your gut, bones and joints. 

Many people - including our own Mumsnet users - are turning to collagen supplements. But before you start shopping yourself, we want to address the fundamental questions you might have about collagen, its benefits, and whether taking supplements is the right choice for you. 

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What are the different types of collagen?

Collagen comes in many forms. In fact there have been roughly 28 different types identified. But there are five main types we tend to discuss the most.

• Type 1 is the most abundant, and makes up about 90 percent of the body’s total collagen. This type provides structure to the body including skin, connective tissues, teeth, bones, and tendons. 

• Type 2 is typically found in cartilage around the joints.

• Type 3 has a structural role, supporting the muscles, organs, and arteries.

• Type 4 is found in the layers and membrane of your skin.

• Type 5 can be found in hair and also the placenta during pregnancy.

As our body's main protein, collagen can be found in many forms

Natural ways to boost collagen production

Your diet plays a crucial role in supporting your body's natural collagen production. To understand what collagen needs to form properly, focus on consuming:

Protein-rich foods

Your body requires specific amino acids—glycine and proline—to build collagen effectively. Include these protein sources:

• Meat and poultry

• Fish and seafood

• Dairy products

• Eggs

• Legumes and beans

Vitamin C sources

Vitamin C helps regulate natural collagen production, making it essential for maintaining healthy levels. Include plenty of:

• Citrus fruits

• Berries

• Leafy greens

• Bell peppers

• Broccoli

“Protein is the bigger story here. Collagen is one type of protein, but we need adequate protein overall to support muscle, hormones, immunity, and recovery. Right now protein is finally getting the attention it deserves — especially for women over 40,” says Pozner.

She adds: “Muscle isn’t just about looking toned; it helps stabilise joints, maintain bone density, regulate hormones, and even support immunity. I often tell patients it’s one of our best long-term health investments.”

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Does collagen decrease with age?

The body's largest organ is the skin and it's made up of two layers. The dermis is the deepest and this is where you'll find collagen. Collagen and elastin work together to give our skin shape and firmness, and the body is constantly renewing collagen. 

Because our natural collagen production slows down after the age of 25 years old, the desire to boost levels via other means has risen. As well as a collagen-rich diet, you may also want to try collagen supplements.

What are collagen supplements? 

Our bodies naturally produce collagen but you can also extract it from several sources, which are used to create collagen supplements. The most common are bovine and marine collagen.

• Bovine is typically sourced from cattle.

• Marine collagen is extracted from fish, typically the bones, scales and skin.

Vegan alternatives are becoming more available, though they don't contain actual collagen. Instead, they provide nutrients that support your body's natural collagen production.

“Here’s where we need a reality check. Supplements can be helpful if your diet is lacking, but they’re not magic. Collagen you eat is broken down into amino acids, just like any protein. Your body then decides how to use them. So unless you’re deficient, collagen powder won’t suddenly erase wrinkles,” says Carla.

Dr Daniel agrees: “Supplements are tested before they’re sold, so collagen should therefore be safe for most people to take. But there are some people who might need to be cautious about taking it — collagen is usually derived from animal sources (beef and pork), but can also come from fish. So if you have allergies to any of these, collagen supplements could cause a reaction.”

Forms of collagen supplements

Collagen supplements have become increasingly popular as people seek ways to support their body's declining natural production.

Collagen supplements come in several forms:

• Powder form is popular because it's easy to mix into drinks and food without affecting taste when choosing high-quality options.

• Capsules offer convenience for busy lifestyles and precise dosing.

• Liquid forms provide ready-to-drink options but may have shorter shelf lives.

These supplements often use hydrolysed collagen or collagen peptides, which essentially means that the collagen has been broken down into smaller peptides that are easier for the body to absorb.

“I’d add that balance matters more than chasing a fad. If you’re eating enough protein, colourful veg, and healthy fats, you’re already giving your body what it needs to build collagen naturally,” Pozner notes.

Collagen supplements shouldn't replace a healthy diet

Weight loss injections and collagen

Given the recent popularity of weight loss injections, we've seen a surge in conversations around both WLIs and collagen. This is because some users are concerned over collagen loss as they undergo treatment.

When weight is lost rapidly, especially in the face, it can result in noticeable changes in skin elasticity and volume. That's where collagen comes into play.

Signs of collagen loss after weight loss include:

• Flattening of the cheeks or temples

• Deepening smile lines

• Skin that looks thinner or more fragile

• Sagging around the jawline and neck

• A tired or hollow look in the eyes and mid-face

It's no surprise then, that alongside conversations around weight loss injections, we've seen Mumsnet users discussing collagen supplementation and how else they can boost collagen in their health and beauty routines.

That said, supplements shouldn't replace a healthy diet.

How to choose the right collagen supplement for you

Purity and quality

Some low-grade collagen supplements may contain contaminants, such as mould or heavy metals like mercury, pesticides and other toxic substances. It’s always vital you check the label. 

When choosing collagen supplements, consider the farming methods: for bovine sources, look for natural farming certifications like the Soil Association that limit pesticides and hormones, while for marine sources, opt for wild-caught fish over farmed varieties, as they typically have better nutrient profiles due to their natural diet and active lifestyle - unlike farmed fish which may face health issues from confined spaces and grain-based diets.

Source quality

Most collagen supplements are either bovine or marine-sourced, so it’s important to check whether these work with your dietary requirements. You may also want to consider the benefits of each collagen too. Type 1 like bovine and marine offer whole-body benefits to your skin, hair, nails, bones, gut and joints. Whereas Type 2 is designed for targeted joint support. 

“You should always buy collagen, or any supplements, from a trusted source," shares Dr Daniel. "This could be your local pharmacy or supermarket even, but always avoid buying supplements from companies you’re not sure about, especially online.”

Dosage and form

Collagen supplements may come in powder, liquid or capsule form, so which one will work best for your daily life? Powdered supplements are popular as often it can be difficult to get the required amount of Type 1 collagen into a single capsule. Powders are easy to add to your morning smoothie or a bowl of porridge, too. That said, capsules are great for on the go.

“As for actual collagen supplements, aim for those labelled as ‘hydrolysed’ as they’re usually more easily digested," explains Dr Daniel, "and avoid any with any artificial sweeteners or anything else you’re not sure about. But before you start taking collagen, it might be worth checking that it’s safe to do so with your GP.”

What Mumsnet users say

"I've just started taking marine collagen last week. Big decision for me as I'm a vegan but while I can live with my perimeno thinning hair the joint pain was really affecting my life." henlake7

"I use Vital Proteins. Don't bother with the capsules, the difference in the amount of collagen in a capsule compared to a powder is massive!!!! I think I worked out I would need 20 capsules to match one scoop of the powder 🤣. I've read it can take 3 months of constantly taking it to notice a difference. I'm on month 2 and my skin feels clearer." xyz111

"I've suffered from significant hair loss for a few years and started taking both bovine collagen (powered) and marine collagen (capsules) around 4 months ago. My hairdresser commented last month that my hair was thicker, I'd not told her anything about the collagen so I guess it must be true that it's helped with some regrowth as opposed to wishful thinking on my part!" ShakeNvacStevens

"I take bovine collagen every morning (in a small fruit juice) and have been doing so for around a year. I'll be taking it for the rest of my life. My skin is in glowing. My hair is thick. And I put my body through a lot of abuse with my exercise regime, and don't have a single ache." PoppyBaxter

"I started taking the capsules a couple of years ago for fibromyalgia pain. It definitely helped. I didn’t notice it until I stopped and realised the pain was getting worse again. it definitely helped my face too, I’ve always been told I look young for my age but my flares were making me look so tired and worn out. I found the marine collagen helps me look less tired than I’m feeling at times." AliceMcK

Collagen plays a vital role in maintaining your body's structure and function throughout life. While natural production declines with age, understanding your options - from dietary sources to high-quality supplements - can help you support your body's collagen needs effectively.

“Collagen has its place, but the bigger picture is lifestyle. A balanced diet, stress management, exercise, and good sleep will do more for your skin, joints and energy than any single supplement ever could,” Pozner reminds us.

Whether you're interested in collagen for beauty benefits, joint support, or overall wellness, focusing on quality sources and realistic expectations will serve you best.

Remember to consult with healthcare providers when making significant changes to your supplement routine, especially if you're considering medical treatments like weight loss injections alongside your wellness plan.

About the experts

• Dr Daniel Atkinson is the Clinical Lead at Treated.com, an online healthcare service company.

• Carla Pozner, Osteopath and Wellness Expert, specialises in women’s health, prenatal and postnatal care and offers a holistic approach to supporting mothers and families through all stages of their wellness journey. Find her on Instagram or at The Portland Clinic. 

About the author

Our resident Leeds lass, Rebecca Roberts is a Senior Content Editor here at Mumsnet. On a daily basis, she commissions, writes and edits content designed to help parents navigate real life - from product reviews to practical features on everything from sex and relationships to fashion to skincare.

Alongside her work, Rebecca is also on her own weight loss journey as part of a medically supervised plan. Beyond her role as an editor, she can be found balancing life as a working mum of two toddlers and when she’s not at her desk, you’ll likely find her at a PTA meeting, in a nearby coffee shop, or walking her two dogs up and down country lanes.

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