Clinical Insights

Beyond Beauty: The Protein Behind Healing, Movement and Resilience Collagen is usually associated with skin. Smoother texture, greater elasticity and fewer visible signs of ageing tend to dominate the conversation. But collagen does much more beneath the surface. It is the most abundant protein in the human body, making up around 30% of our total protein. It provides structure to our skin, bones, cartilage, tendons and ligaments—and plays an important role in how these tissues repair and renew themselves. When we are injured or undergo surgery, the body produces new collagen to help rebuild damaged tissue. When we move and exercise, collagen-rich cartilage, tendons and ligaments help our bodies absorb force, transfer movement and remain stable. Even our bones depend on a collagen framework for strength and resilience. These functions become increasingly important as we age. Because healthy ageing isn't only about how we look. It is also about how well we heal, move, recover and remain physically capable. So what role does collagen supplementation play—and can providing more of its building blocks help support these processes? To answer that, we need to look beyond the skin and understand what collagen is doing throughout the body. What Is Collagen—and Why Does the Body Need It? Collagen is the body's main structural protein. Rather than performing one specific job, it forms a framework that gives different tissues strength, flexibility and support. There are at least 28 known types of collagen, but three are particularly relevant to everyday health. Type I is the most abundant. It is found in skin, bones, tendons and ligaments, where strength and resistance to pulling forces are important. Type II is concentrated in cartilage, helping create the smooth, resilient tissue that cushions our joints. Type III often works alongside Type I and is found in skin, muscles, blood vessels and internal organs. Together, these collagen fibres form part of the extracellular matrix—the supportive structure surrounding our cells and holding tissues together. Collagen Is Constantly Being Rebuilt Collagen isn't a permanent structure. The body continually breaks down old collagen and produces new collagen, although the speed of this turnover varies considerably between tissues. This process becomes particularly important when tissue is damaged. Following an injury or surgery, collagen helps form the new extracellular matrix needed to rebuild damaged tissue. As healing progresses, newly formed collagen fibres are reorganised and remodelled, gradually giving the repaired tissue greater strength and structure. The same process of collagen synthesis and remodelling is also happening—at different rates—in our tendons, cartilage, bones and other connective tissues throughout life.   What Changes as We Age? Our relationship with collagen changes as we get older. Collagen formation and breakdown become altered with age, and existing collagen can undergo structural changes that affect the properties of our tissues. These changes vary by collagen type, tissue and sex rather than following one simple age-related decline. Lifestyle matters too. Factors such as UV exposure and smoking can accelerate collagen damage, while nutrition and physical activity influence the environment in which connective tissues are maintained and remodelled. The effects aren't limited to wrinkles. Age-related changes to collagen-rich tissues can influence how our joints, tendons, bones and skin perform and recover. So What Happens When We Take Collagen? Most collagen supplements contain hydrolysed collagen, or collagen peptides. Hydrolysis breaks the large collagen protein into smaller peptides that are easier to digest and absorb. Once consumed, collagen may support the body's own collagen production in two ways. First, it provides the building blocks. Collagen is particularly rich in glycine, proline and hydroxyproline—amino acids the body uses to make new collagen. Second, some small collagen-derived peptides can enter the bloodstream intact. Researchers believe these peptides may also act as biological signals, encouraging cells involved in connective tissue to produce more collagen. In other words, collagen supplementation doesn't simply replace old collagen with new collagen. It provides the raw materials—and potentially some of the signals—the body can use to support its own collagen production. Collagen Beyond Skin: Recovery, Movement and Resilience Collagen is constantly at work beneath the surface—helping tissues repair after injury, supporting our joints through everyday movement and giving connective tissues the strength to withstand physical stress. These roles make collagen much more than a beauty protein. It is an important part of how the body heals, moves and remains physically resilient. Healing & Recovery When tissue is damaged through injury or surgery, the body needs to rebuild the structural framework that has been disrupted. Collagen is central to this process. During healing, specialised cells called fibroblasts produce new collagen, creating a framework for repairing damaged tissue. Over time, those collagen fibres are reorganised and strengthened as the tissue remodels. This process doesn't happen overnight. Collagen formation and remodelling continue long after a wound appears to have healed on the surface. Nutrition matters during this period because the body needs adequate protein, amino acids and micronutrients to build new tissue. Collagen peptides provide particularly high concentrations of glycine, proline and hydroxyproline—the amino acids commonly found in collagen itself. For a deeper look at how nutrition supports healing after surgery, we explore this further in A Surgeon's Perspective: What Your Body Needs to Heal, Recover and Build Resilience. Protecting Joint Health & Mobility Everyday movement puts our joints to work. Cartilage cushions the bones where they meet, while collagen helps give that cartilage its strength and resilience. As we age, cartilage can gradually change and become less resilient. In conditions such as osteoarthritis, its breakdown can contribute to joint pain and stiffness. This is one of the areas where collagen supplementation has attracted the most clinical research. Studies suggest that oral collagen supplementation may help reduce joint pain and stiffness and improve physical function, particularly in people with osteoarthritis. Research has also explored its use in physically active adults experiencing activity-related joint discomfort. For active and ageing adults, supporting joint comfort and mobility can make an important difference to staying physically active.  Supporting Tendons & Ligaments Through Recovery Muscles tend to get most of the attention when we exercise or recover from injury. But movement depends just as much on the connective tissues supporting them. Tendons connect muscle to bone, while ligaments connect bones and help stabilise our joints. Both are dense, collagen-rich tissues designed to withstand considerable physical force. When injured, they can also be frustratingly slow to recover. Their relatively limited blood supply and slow rate of tissue remodelling mean that sprains, strains and overuse injuries can take considerable time to heal. Collagen is central to this repair process. As damaged connective tissue heals, new collagen is produced and gradually reorganised to restore strength and function. This has led researchers to investigate whether collagen supplementation can provide additional nutritional support during rehabilitation. Studies combining collagen peptides with resistance or loading exercise suggest that supplementation may support tendon structure, strength and adaptation.  Exercise stimulates connective tissues to adapt and strengthen, while collagen peptides provide the building blocks the body uses to produce new collagen. Together, they can support the ongoing repair and resilience of tendons and ligaments.  Supporting Recovery From Exercise Exercise doesn't challenge our muscles alone. Tendons, ligaments and other connective tissues are also placed under load and need to adapt and recover. Collagen is particularly rich in glycine, proline and hydroxyproline—the amino acids the body uses to build collagen in these tissues. This has led to growing interest in collagen supplementation as part of exercise recovery, particularly when combined with training. Vitamin C also plays an important role because it is essential for collagen synthesis. Some research has explored taking collagen or gelatin with vitamin C before exercise, with evidence that the combination can increase markers of collagen synthesis in response to physical loading. For active adults, collagen's role in recovery may therefore be less about building bigger muscles and more about supporting the connective tissues that keep those muscles moving. Bones Need Collagen Too When we think about strong bones, calcium usually comes to mind. But collagen is also an essential part of bone structure. Collagen forms a flexible framework within the bone, which is then strengthened by minerals such as calcium and phosphate. Together, they give bones the combination of strength and resilience needed to withstand everyday forces. As we age, changes in this collagen framework can affect bone quality. This has led researchers to investigate whether collagen supplementation can help support bone health, with some human studies reporting encouraging effects on bone formation and bone mineral density. So supporting bone health isn't only about minerals. Maintaining the collagen framework they are built around matters too. What About Gut Health? Collagen is increasingly promoted for “gut repair” and supporting the intestinal barrier. Part of this interest comes from its high glycine content, an amino acid involved in tissue repair and studied for its role in intestinal health. The theory is plausible: collagen provides amino acids that may support the tissues forming the gut barrier. But the human clinical evidence has not yet caught up with the claims. At present, there isn't enough high-quality research to conclude that taking collagen peptides can repair intestinal permeability or treat gastrointestinal conditions. Gut health remains an interesting area for collagen research, but for now, the evidence is much stronger for its role in connective tissues such as joints, tendons and bones. Collagen is far more than a beauty ingredient or another protein powder. Collagen supplementation provides targeted building blocks for the tissues that allow us to heal, move, recover and remain physically resilient throughout life.  How to Support Collagen Production Our bodies make collagen naturally, but the process depends on having the right raw materials and nutrients available. Diet, lifestyle and supplementation can all play a role. Start With the Building Blocks Collagen is a protein, so producing it requires amino acids. Protein-rich foods such as meat, fish, poultry, eggs, dairy, legumes and soy provide amino acids the body can draw upon to build and repair tissues. Foods containing connective tissue—such as bone broth, chicken skin, fish skin and slow-cooked cuts of meat—also contain collagen or gelatin directly. But eating more collagen isn't the only consideration. The body also needs specific nutrients to turn those building blocks into new collagen. Vitamin C Is Essential Of all the nutrients involved in collagen production, vitamin C is one of the most important. The body needs vitamin C for key enzymatic steps that stabilise newly formed collagen. Without enough of it, normal collagen synthesis is impaired. This is why severe vitamin C deficiency causes symptoms such as poor wound healing and fragile connective tissue. Good sources include citrus fruits, berries, kiwi, capsicum, broccoli and leafy vegetables. This relationship has also prompted researchers to investigate collagen or gelatin together with vitamin C around exercise, when connective tissues are being mechanically stimulated. Early research suggests this combination may support collagen synthesis, although the optimal dose and timing are still being studied. Don't Forget Zinc and Copper Zinc and copper also contribute to normal connective-tissue formation and repair. Zinc is involved in protein synthesis, cell growth and wound healing, while copper is required by enzymes that help cross-link collagen fibres, giving connective tissues strength and stability. Rather than thinking of collagen production as dependent on one “hero” nutrient, it is better understood as a process requiring adequate protein alongside a range of vitamins and minerals. Where Collagen Peptides Fit In A balanced diet provides the nutrients needed to make collagen. Collagen peptide supplementation offers a more concentrated source of collagen-specific amino acids and peptides. As we discussed earlier, hydrolysed collagen provides high levels of glycine, proline and hydroxyproline. Some smaller peptides can also enter the circulation intact and may have signalling effects on cells involved in connective-tissue metabolism. This makes collagen peptides different from simply adding more general dietary protein—particularly when the goal is to support collagen-rich tissues such as joints, tendons, ligaments and bone. Not All Collagen Comes From Animals Traditionally, collagen supplements have been derived from animal tissues. Bovine collagen typically comes from cattle hides and bones, marine collagen from fish skin and scales, while porcine and poultry tissues can also provide different forms of collagen. But animal tissue is no longer the only way to produce collagen. Advances in biotechnology are making it possible to produce non-animal collagen and collagen-like proteins through fermentation. Instead of extracting collagen from hides, bones or skin, microorganisms are used as biological production systems to create specific proteins or peptides under controlled manufacturing conditions. Advances in biotechnology are making it possible to produce non-animal collagen and collagen-like proteins through fermentation. Instead of extracting collagen from hides, bones or skin, microorganisms are used as biological production systems to create specific proteins or peptides under controlled manufacturing conditions.   Fermentation-derived products can instead contain proteins designed to share structural characteristics with particular types of collagen. For example, PearlRx Collagen 99 uses COLLAWISE™, a non-animal, fermentation-derived collagen that shares structural features with human Type III collagen.   This emerging technology also raises an interesting question about where our supplements come from. Conventional animal-derived collagen makes use of valuable animal by-products, but it remains connected to livestock or seafood supply chains and requires multiple stages of extraction and processing. We explore that journey—and its environmental considerations—in Acid Washes and Carbon Footprints: The Processing of Animal-Derived Collagen. Fermentation technology now makes it possible to produce collagen without animal sources, reducing reliance on livestock and the associated environmental burden. It represents an important advancement in how collagen can be produced and offers consumers a new alternative with fewer ties to resource-intensive animal supply chains.  Built to Move Our bodies are designed to move. But movement depends on more than muscle. Every step, stretch and lift relies on a network of collagen-rich tissues working together—cartilage absorbing pressure, tendons transferring force, ligaments stabilising joints and bones providing the framework beneath it all. These structures also need to repair and renew themselves throughout life. As a surgeon, I view healthy ageing as the total package: looking great, feeling great, and keeping your body performing at its peak. It’s about maintaining the energy, strength, mobility, and recovery needed to stay active and independent—proactively doing what supports us physically, mentally, and emotionally. Dr Pearlie Tan, Founder of PPS Wellness Looking after collagen is therefore about more than skin. It is about supporting the physical framework that allows us to move, recover and remain resilient for longer.

Discover the key factors that support healing, recovery and resilience, from nutrition and hydration to sleep, skin health and lifestyle habits. A science-based look at what the body needs to recover effectively.

From Lifespan to Healthspan For decades, the goal of healthy ageing was largely about lifespan—how long we live. Today, the conversation is increasingly about healthspan—how long we can remain healthy, active and functioning well as we age. This shift has encouraged scientists to look more closely at what happens inside our cells over time. One molecule attracting particular attention is NAD+ (nicotinamide adenine dinucleotide). NAD+ is essential for cellular energy production. It also supports DNA repair, cellular maintenance and the body's response to physiological stress. As we age, NAD+ metabolism changes and its availability may decline in some tissues, raising an intriguing question: could supporting NAD+ help our cells function better for longer? This is where NMN (nicotinamide mononucleotide) comes in. If we think of our cells as engines, NAD+ helps provide the fuel that keeps them running. NMN is one of the building blocks the body uses to replenish that supply. This relationship has made NMN one of the most closely studied molecules in healthy ageing research. Animal studies have produced promising results, while a growing number of human trials are beginning to explore its effects on NAD+ levels, metabolism, physical function and other markers associated with ageing. The science is still evolving, and NMN is not a proven way to reverse ageing. But its close relationship with NAD+ provides a compelling biological reason to investigate its potential. Understanding what NAD+ does—and how NMN helps the body make it—is a useful starting point for understanding where the science of healthy ageing may be heading. What Are NAD+ and NMN? NAD+: Powering Our Cells NAD+ (nicotinamide adenine dinucleotide) is a coenzyme found in every living cell. It plays an essential role in converting the food we eat into ATP—the energy our cells use to function. NAD+ is also required by enzymes involved in DNA repair, cellular maintenance and the body's response to physiological stress. Without enough NAD+, many of these processes cannot operate normally. Research suggests that NAD+ availability changes as we age and may decline in some tissues. This has led scientists to investigate whether maintaining NAD+ metabolism could help support healthier cellular function later in life. NMN: A Direct Precursor to NAD+ NMN (nicotinamide mononucleotide) is a naturally occurring compound and a direct precursor to NAD+. In simple terms, it is one of the molecules our bodies use to make NAD+. NMN sits close to the end of the body's NAD+ production pathway. Once available for NAD+ synthesis, it requires just one enzymatic step—through enzymes called NMNATs—to be converted into NAD+. This direct relationship is what makes NMN particularly interesting in longevity research. Why Not Simply Take NAD+? It seems logical: if we want more NAD+, why not supplement NAD+ itself? Three main biological barriers explain why: Molecule Size & Transport NAD+ is a large, bulky molecule (around 663 g/mol) that cannot easily cross cell membranes intact. Cells lack direct, efficient transporters to take up full NAD+ molecules from the bloodstream. NMN, by contrast, is half the size (around 334 g/mol) and utilizes dedicated cellular transporters (such as Slc12a8) to pass directly into cells. Digestive Breakdown When consumed orally, intact NAD+ is rapidly degraded by stomach acid and digestive enzymes in the gut long before it can reach your bloodstream or target tissues. It breaks down into smaller subunits like nicotinamide (NAM), forcing your body to reassemble it from scratch through lengthy metabolic pathways. Cellular Conversion Speed NMN acts as the immediate structural precursor to NAD+ in the body's internal "salvage pathway". Once NMN enters a cell, it requires only a single enzymatic step (catalyzed by NMNAT) to convert directly into active NAD+.   Direct NAD+ delivery is only effective when given via IV or subcutaneous injection to bypass the digestive tract, whereas NMN has high oral bioavailability and easily elevates tissue NAD+ levels when taken as a pill. Why NAD+ Matters for Healthy Ageing NAD+ is involved in some of the most fundamental processes that keep our cells functioning. This is why changes in NAD+ metabolism have attracted so much interest in ageing research.   Cellular Energy & Mitochondrial Function Every cell needs energy to function. Much of this energy is produced by the mitochondria—the tiny powerhouses inside our cells. NAD+ plays a central role in this process, helping convert nutrients from food into ATP, the usable energy that powers cellular activity. As we age, mitochondrial function can become less efficient. Researchers are therefore studying whether supporting NAD+ metabolism could help maintain cellular energy and mitochondrial function as we get older. DNA Repair & Cellular Defence Our DNA is constantly exposed to damage from normal metabolism, UV radiation and environmental stress. NAD+ is used by enzymes called PARPs, which help detect and repair damaged DNA. It is also closely linked to sirtuins, a family of proteins involved in cellular stress responses, metabolism and healthy ageing. Both processes consume NAD+, creating an important connection between our NAD+ supply and the cell's ability to maintain and repair itself. Metabolic & Cardiovascular Health NAD+ is also involved in how the body regulates glucose, insulin sensitivity and vascular function. This has led researchers to investigate NMN in areas such as metabolic health and cardiovascular ageing. Some human studies have reported encouraging findings—including improvements in muscle insulin sensitivity in a trial involving women with prediabetes—but results across studies remain mixed. Brain Health & Cognitive Function The brain has exceptionally high energy demands, making healthy mitochondrial function particularly important. NAD+ is involved in neuronal energy metabolism, DNA repair and cellular responses to oxidative stress. Animal research has generated considerable interest in whether NAD+ precursors could help protect brain function during ageing. Human evidence, however, is still limited. It is too early to say that NMN supplementation improves memory or prevents cognitive decline. Muscle Function & Physical Performance Muscle health is an important part of healthspan. Maintaining strength, mobility and endurance helps us remain independent and active as we age. Because skeletal muscle depends heavily on mitochondrial energy production, researchers have also investigated whether NMN supplementation can influence physical performance. Early human trials have produced some encouraging results in measures such as walking performance and aerobic capacity, but the evidence is not yet consistent enough to consider NMN an established intervention for physical performance. The Bigger Picture These different areas share a common thread: NAD+ sits at the intersection of energy production, cellular maintenance and the body's response to stress. That does not mean increasing NAD+ will automatically improve every process associated with ageing. But it explains why NAD+—and precursors such as NMN—have become such an important focus of longevity research.   How to Support NAD+ Levels NAD+ is continuously produced, used and recycled by the body. While supplementation has attracted attention, our everyday habits also influence the metabolic pathways that regulate NAD+. Exercise Regular exercise is one of the most established ways to support healthy mitochondrial function and NAD+ metabolism. Both aerobic and higher-intensity exercise increase the energy demands placed on our cells, triggering adaptations that help mitochondria produce energy more efficiently. Exercise can also influence enzymes involved in maintaining and recycling NAD+. It is another reason physical activity remains one of the most powerful tools we have for healthy ageing. Nutrition The body can make NAD+ from several forms of vitamin B3 and related precursors obtained through food. NMN itself occurs naturally in small amounts in foods including edamame, avocado, broccoli, cucumber, cabbage and tomatoes. However, the quantities are far lower than those typically used in NMN supplements. A balanced diet therefore supports the body's normal NAD+ metabolism, but food and NMN supplementation are not directly equivalent. Sleep and Circadian Rhythm NAD+ metabolism is closely connected with the body's circadian clock, the internal system that coordinates sleep, metabolism and cellular activity across the 24-hour day. Maintaining regular sleep and wake patterns supports this broader metabolic rhythm. Rather than thinking of sleep as a direct “NAD+ booster,” it is better understood as part of the healthy cellular environment in which NAD+ metabolism operates. NMN and NR: What the Research Shows NMN is not the only NAD+ precursor being studied. Nicotinamide riboside (NR) is another naturally occurring molecule that can ultimately be converted into NAD+. Both NMN and NR have been shown to raise NAD-related biomarkers in humans, although they follow somewhat different metabolic routes. Researchers are still working to understand whether one offers meaningful advantages over the other in different tissues or individuals. Supporting the System, Not Just the Molecule NMN is an interesting way of supporting the NAD+ pathway, but it should not be viewed in isolation. Exercise, good nutrition, restorative sleep and metabolic health remain the foundations of healthy ageing. Supplementation is best considered alongside these habits, rather than as a substitute for them. Safety, Dosage and What We Know So Far Human research into NMN is still relatively young, but its short-term safety profile has so far been reassuring. A 2026 review of 15 randomized controlled trials found that doses ranging from 250 to 2,000 mg per day, taken for between two weeks and six months, did not significantly increase adverse events or markers of liver injury. Individual studies have also tested doses as high as 1,250 mg daily for four weeks in healthy adults without serious adverse effects.   How Much NMN Should You Take? There is currently no established optimal dose for healthy ageing. Clinical studies have investigated a wide range of doses, often from a few hundred milligrams upwards. More is not necessarily better, and the amount required to raise NAD+ biomarkers may not be the same as the amount needed to produce a meaningful health benefit. This is one of the questions ongoing research still needs to answer. What Does the Human Evidence Show? The clearest finding is that NMN can influence NAD+ metabolism in humans. Some individual trials have also reported encouraging results in areas such as insulin sensitivity, aerobic capacity and physical function. But the overall picture remains mixed. The latest meta-analysis found good short-term tolerability but no consistent improvement across common measures such as body weight, fasting glucose, HbA1c, cholesterol or systolic blood pressure. So while NMN has a compelling biological rationale, raising NAD+ and proving a long-term improvement in healthspan are not the same thing. Quality Matters As with any supplement, the contents of the bottle matter as much as the ingredient on the label. Look for products that clearly state the amount of β-NMN, provide information about manufacturing standards and use independent testing to verify purity and contaminants. Long-term safety data are still developing, so NMN should not be treated as a substitute for established approaches to healthy ageing. People who are pregnant or breastfeeding, taking medication or managing a medical condition should seek medical advice before supplementation. A Surgeon’s Perspective on Healthy Ageing and Longevity    As a surgeon, I view healthy ageing as the total package: looking great, feeling great, and keeping your body performing at its peak. It’s about maintaining the energy, strength, mobility, and recovery needed to stay active and independent—proactively doing what supports us physically, mentally, and emotionally. This is why I find the research into NAD+ and NMN particularly interesting. NAD+ sits at the centre of cellular energy production and is involved in processes such as DNA repair and cellular maintenance. NMN offers a way of supporting the body's own pathway for producing NAD+, which makes it a compelling area of healthy ageing research. — Dr Pearlie Tan, Founder of PPS Wellness     The human evidence is still developing. We know that NMN can influence NAD+ metabolism, but we do not yet know whether this will translate into longer-term improvements in healthspan. Current reviews similarly find clear biological activity but mixed clinical outcomes, which is why larger and longer human studies remain important. For me, healthy ageing has never been about finding a single molecule that promises to turn back time. It is about supporting the biological systems that allow us to function well for as long as possible. Exercise, good nutrition, quality sleep and maintaining muscle and metabolic health remain fundamental. But as our understanding of ageing biology advances, compounds such as NMN give us another interesting avenue to explore. We cannot stop ageing, but science is giving us a better understanding of how we age—and potentially, more tools to help us age well.