Collagen Claims, Clear Science

Collagen promises smoother skin, happier joints, and faster recovery, but what holds up when we strip away the hype and read the best studies? 

We unpack the newest research since 2023 and draw a clear line between modest, measurable effects and results that melt under tighter controls. If you’ve wondered whether those powders and gummies are worth the price, this conversation gives you honest context without shaming your choices.

We start by laying out how to read supplement science: funding bias, placebo controls, sample size, and why meta-analyses can mislead when they pool weak trials with a few strong ones. 

For joint pain, we highlight small to moderate improvements in osteoarthritis outcomes seen in several meta-analyses, balanced by a rigorous trial that found no advantage over placebo. The takeaway is measured: collagen is not a cure, but some people feel a little better, especially alongside strength training, movement, and weight management.

Skin health is a different story. 

We dig into a 2025 meta-analysis showing that benefits largely appear in industry-funded studies, while high-quality independent trials see no meaningful changes in wrinkles, hydration, or elasticity. We explain the biology, collagen is digested into amino acids, and why sunscreen, sleep, protein-rich whole foods, vitamin C, zinc, copper, and smart skincare move the needle more. 

On muscle and recovery, we clarify that collagen is an incomplete protein and poor at stimulating muscle protein synthesis, yet may support connective tissues when paired with resistance training, offering small improvements in recovery or fat-free mass for some.

You’ll walk away with practical priorities: train progressively, eat enough complete protein, protect your skin from the sun, sleep deeply, and manage stress. If you choose to test collagen, define your goal, set realistic expectations, track changes, and reassess your budget. 

If this helped you think clearer about supplements and what actually works, follow the show, share it with a friend who’s collagen-curious, and leave a quick review to help others find us.

Go check out my website for tons of free resources on how to transition towards a healthier diet and lifestyle.

You can download my free plant-based recipes eBook and a ton of other free resources by visiting the Digital Downloads tab of my website at https://www.plantbaseddrjules.com/shop

Don't forget to check out my blog at https://www.plantbaseddrjules.com/blog

You can also watch my educational videos on YouTube at https://www.youtube.com/channel/UCMpkQRXb7G-StAotV0dmahQ

Check out my upcoming live events and free eCourse, where you'll learn more about how to create delicious plant-based recipes: https://www.plantbaseddrjules.com/

Go follow me on social media by visiting my Facebook page and Instagram accounts
https://www.facebook.com/plantbaseddrjules
https://www.instagram.com/plantbased_dr_jules/

Last but not least, the best way to show your support and to help me spread my message is to subscribe to my podcast and to leave a 5 star review on Apple and Spotify!
Thanks so much!

Peace, love, plants!
Dr. Jules

Transcript

Section A

SPEAKER_00 0:10

Yo, Plant Base Buddies, welcome back to season three of the podcast. This year's gonna be amazing. We'll be talking about all of the different pillars of lifestyle medicine, from nutrition to exercise to stress to sleep and everything in between. Yo, Plan Based Buddies, welcome back to another episode of the podcast. Today, we're gonna be talking about one of the most requested subjects I've received since being on social platforms about collagen. Now, collagen is one of the most popular supplements on the planet, and influencers are promoting powders and gummies and coffees, creams, and putting scoops of collagen into everything. Now, it's important to recognize that science does change and evolve. And I reviewed the subject in 2023, and even in this short span of two years, we've seen great and high-quality news studies getting published about collagen. Now, when people ask me whether or not they should be taking this supplement, I ask this question back. Why? Why do you want to take it? What are your goals? Are we talking about skin health and making your skin look more moisturized or younger and reducing the look of wrinkles? Or are we talking about reducing joint pain and helping your arthritis feel better? Or are we talking about muscle gains and recovery? Now, the science surrounding all of these subjects will always keep evolving, and these episodes will also have to keep getting updated. I mean, in two to three years from now, I can just imagine or assume that higher quality studies are gonna get published, and I'm gonna have to come back and talk about it again. So just as my opinion has changed a little since 2023, in the future, I'm gonna have to come back here and re-record an episode on collagen. I'm almost sure of that. Now, some people will look at this and say, well, make up your mind as if evolving with the times is kind of a weakness, and changing your mind with new data is something to be embarrassed about. But that's actually science doing its job, and that's the scientific process in motion. And that's the beautiful thing about getting new data and new research done. We hope that this adds to the bulk of science we already have published on the subject. Now, the most important thing to understand when it comes to publishing scientific research on something like collagen, we need to know if this study is of high quality or not. I mean, is it funded by someone who is trying to sell you collagen supplements? Was it controlled? So maybe people taking supplements like collagen all already have healthier looking skin because they're practicing all sorts of other lifestyle behaviors that could help their appearance. Almost like people who care about these things can absolutely self-select to be part of a research study that looks at collagen's impact on these things. Also, we need to look at whether or not we are comparing collagen against a placebo. Because maybe if you're in a collagen study, you're also making sure to not put harsh chemicals on your body, and maybe you're wanting to exercise more because you're motivated to make your skin healthier and you're drinking more water. Other factors can confound whether or not the collagen is the explanation behind the improvement. And that's why, even with supplements or medications or other behaviors, it's always better to have a placebo. Now, the other thing is how many people were in the research study. If you're studying two people on collagen supplements and one gets better, you can't say it's 50% effective, right? So as we control for confounders, that we randomize people in in the collages control group, as we're comparing against placebo on hundreds, or if not thousands, of people instead of just a dozen, we'll get closer to the answer. And so that's why the quality and power behind a published study can change as we're starting to produce and publish higher quality studies, right? So if you use collagen and you'd like to get to the bottom of where the science is, this is the episode for you. And if you're skeptical, this is not a this is not an episode made to bash collagen. I mean, I'm not here to tell people to use it or not to use it. This is a science episode. The goal is just to have a nuanced look at the subject and remain calm if you feel you've been duped and remain calm if you're desperately looking for a solution to some of your problems. I'm not sure that at the end you'll be pushed to pick sides. I just I think you'll recognize that I was just simply honest about the published study. I'll give my opinion, but I'll I'll have you make your own after. So let's talk through the different main claims that people use for collagen. First one is joints. People claim that it might delay the wear and tear on your joints, maybe even reverse arthritis or make it deteriorate slower as we age. Maybe it will even help if there's already arthritis there to reduce pain. All sorts of claims around joint health are made when it comes to collagen. And the same thing goes with skin. Collagen is a protein that's in your skin and helps it retain its elasticity and thickness and firmness. And so taking collagen may help delay the aging process. And we know that people don't like wrinkles. We have trouble as a society admitting that we're aging or that our functions are aging. And so it's easy to prey on people who are vulnerable and try to sell them a supplement. So, and the other thing is about muscle and recovery. Obviously, I've I'm a guy who promotes fitness and loves to talk about exercise. So, I do understand that there's maybe a role for collagen to play. Collagen is a structural protein in connective tissue and tendons and ligaments, and maybe it could help recover faster. And much in the same way, collagen is a protein. So, protein builds muscle. So, what does the science say in terms of muscle gains? So, we'll look at what the best research actually says and where scientific signals kind of look real, and where these signals tend to fade because of the quality of the science that remains poor. By the end of this episode, hopefully you'll feel informed and not judged on whether or not you have used it in the past or if you plan on using collagen in the future. So let's start with the first part: joint health. So, joint pain is a one of the top reasons that people try collagen, and one of the main reasons that people consult a doctor, knee osteoarthritis or wear and tear of the cartilage of the knee is one of the main forms of arthritis that I see the clinic regularly. Knees and hips are weight-bearing joints, and they kind of tend to wear out quicker than the other ones on average. And this is where collagen has the strongest, though still modest, evidence. Now, in 2024, there was a large meta-analysis that looked at 35 randomized control trials with over 3,000 patients, all of them diagnosed with osteoarthritis. And the findings were not anything magical or front-page news, but it wasn't nothing either. Now, collagen seemed to lead to a small to moderate reduction in pain and modest improvements in function. We're not talking about collagen reversing disease here or having cured people of their pain, but we could still measure a signal. We could still measure a signal that people were improved when it came to joint pain and function. Now, in 2025, we have a newer meta-analysis that confirmed similar findings. People who took collagen seemed to have lower pain scores and better function scores. But again, it was a very small effect. So where does the confusion come from? Well, because when we actually look at higher quality and tightly controlled trials, the results are not as obvious. Now, there was a very well-designed trial in 2025, it's a double-blind trial that found no difference between collagen and placebo over 12 weeks with knee osteoarthritis. And that tells us something important that collagen isn't always a guaranteed solution. Now, the most important thing is I just discussed a few minutes earlier, the quality of the study matters. So if we do a meta-analysis of 35 randomized controlled trials, but 30 of them all are poor trials funded by collagen companies, well, there's no doubt that the meta-analysis is going to show a benefit, right? But if we tease out the high-quality trials from the lower, maybe industry-funded trials, it's almost like the results aren't the same. And the response to collagen seems to be variable in these different studies, depending on the quality of the study. Now that's an interesting nuance. In younger, physically active adults with exercise-related knee pain, a specific collagen peptide dose of 5 grams per day did reduce activity-related pain. So it was compared to placebo. So in these people, we did see a benefit. But that was a different population, maybe even a different mechanism, so we seem to find different outcomes. Now, mechanistically, collagen seems to act in two ways. Undenatured collagen may work through immune modulation, whereas hydrolyzed collagen maybe even provides bioactive peptides, chains of amino acids that appear to actually reach the joint tissues and maybe even support cartilage turnover. Now, I've always been skeptical of this mechanism because just because you eat your fingernails doesn't mean that you are going to have fingernails that grow better and faster, much in the same way as you can't eat your hair to have healthier hair. So eating collagen to support collagen kind of fits in that same analogy. But maybe collagen could get broken down into smaller amino acid chains or small peptides. And these peptides can actually make their way into these tissues and possibly bind with receptors that help stimulate collagen turnover and production. So the takeaway for joints is that if you have osteoarthritis or joint discomfort, collagen may simply reduce slightly your pain and maybe help you improve some function, but not for everyone, just for some people. The effects are modest at best, they're not universal and apply to everyone, and they're definitely not a replacement for moving and strength training and managing your weight or doing physical therapy. So if someone feels better in terms of joint health on it, then your experience is not an imaginary experience, it's not just all in your head. There is some high-quality science saying that function in pain may improve, but your expectations need to be realistic. I mean, if I tell patients to take, instead of taking a 500 milligram dose of tolanol, that you would take 100 milligrams, if we give it to enough people, we may be able to measure a reduction in pain. But I mean, let's be honest, some of you probably are living with chronic pain, some of you most likely have arthritis. And it's not like for those with more advanced conditions, it's not like taking a tolanol or or two is gonna reduce your pain by a hundred percent and magically cure you, right? So if I say that in some studies, people have really minimal improvements in pain and improvements in function, maybe if it's not a lot, it's still there, but that's where you need to decide if that reduction in pain that you feel justifies the cost of taking collagen regularly. So just be realistic if you want to take collagen for joint pain and joint function. There are high-quality studies seeming like they're showing benefit, but you may have heard of the the slogan garbage in, garbage out. If you put garbage studies inside of a meta-analysis and spits out one answer to whether or not it works or not, you'll get garbage as an answer, right? So the quality of the studies that you're looking at when you're doing a meta-analysis absolutely counts to provide a really reliable answer. Right on. Now let's stick to part two collagen and skin health. Now, skin is where collagen marketing explodes, and it's the most marketed claim when it comes to collagen. They promote reductions in wrinkles and improved elasticity, and your skin will glow and you'll look younger. And this is where the science kind of gets murky, and that I feel uncomfortable as a doctor recommending collagen specifically to patients. Now, in 2025, a very important meta-analysis looked at 23 randomized controlled trials on collagen and skin aging. There was over 1,400 participants. And here is the key finding. Now, when studies were not funded by collagen companies, by industry, collagen showed no meaningful impact on skin hydration, measures of elasticity, or wrinkles. But when you look just at the studies that were funded, all of a sudden benefits appear. Now that's a red flag, and the same pattern appeared when looking at study quality. High quality trials seem to show no effect and no improvement in skin elasticity, wrinkles, or glow or youthfulness. Whereas if you looked at lower quality trials, they showed improvement. And earlier meta-analyses from 2021 to 2023 did report positive skin outcomes, so improvement in skin parameters after about three months or 90 days of supplementing with collagen. But these analyses did not fully account for funding bias. Now, this doesn't mean that collagen doesn't work for your skin, just means that the evidence is very fragile and very influenced by the people who paid for the research. Now, biologically, collagen is broken down into amino acids during digestion. So your skin is not absorbing collagen as an intact protein. Same way as you even if you eat hair, your hair doesn't grow better. Now your body will rebuild collagen using different amino acids and vitamin C and copper and zinc and other minerals and energy. So if someone improves their protein intake overall, eats a healthier diet with more micronutrients and reduces smoking and UV exposure, skin health will improve. Now, collagen will often get credit in those cases, but may not necessarily be the main pillar. So when it comes to skin health and collagen supplementation, to be honest, there's no strong independent evidence that collagen reliably improves wrinkles or skin aging when you're looking at high-quality, non-industry funded research. Now, if someone tells me that they take collagen and they feel like it's helping their skin and they have less joint pain and they feel better while taking it, their experience matters. But from a scientific standpoint, collagen doesn't seem to be essential for skin health if we're talking about supplementation. Now I'm not saying it works and I'm not saying it doesn't. I'm saying that if we tease out the high-quality studies, they don't seem to show a benefit. But when we look at the industry-funded biased research, it does seem to show a benefit. So it's natural that if you have 30 industry-funded research studies and you have two or three well done, and you crunch them up into one meta-analysis, the bulk or the average results may show benefit. That's where it's very still controversial. I think that patient experience will determine if they wanna and budget will determine if they want to keep taking it. But that's why it's not necessarily a blanket supplement that I recommend to most people, because it costs a fortune and the goal is to make people use them long term and it needs to be sustainable. And I honestly think you should be focusing your energy at even more important behaviors when it comes to skin health. But talk about that at the end of the episode. Now, when it comes to muscle gains and muscle recovery, it's important to know that collagen isn't even a complete protein. It's slow in essential amino acids, especially leucine, that is the most talked-about amino acid when it comes to triggering muscle protein synthesis, and it's deficient in tryptophan. So, collagen is a very poor protein when it comes to muscle building. But what's weird is that when you compare collagen head-to-head with higher quality proteins for muscle protein synthesis, collagen loses, and that's consistent and expected. But we have some meta-analysis showing that when collagen peptides are actually combined with long-term resistance training, people they gain slightly more fat free mass. They could experience improvements in muscle architecture and small improvements in strengths when compared to training alone. And another randomized controlled trial showed that 15 grams of collagen daily, when you combine it with resistance training. It increased fat-free mass more than training alone. And if you're asking yourself, how does that make sense if collagen is an incomplete protein, unable to trigger muscle protein synthesis? Well, because muscle isn't just contractile protein, its tendons and its connective tissue, fascia, extracellular matrix. Scaffolding, holding the muscle together, that turnover relies a lot on glycine and proline, which collagen is already rich in. So collagen may support that scaffolding around the muscle rather than actually do anything for muscle fibers themselves. Now, this doesn't make collagen a superior protein, but it makes it something worth considering. Now, another important nuance is that collagen should never replace a high-quality protein. If someone is under-eating protein and chooses collagen instead of legumes, soy or other complete protein sources, that's not optimal. But as an add-on, if people are already training consistently and consuming significant amounts of high-quality proteins, collagen may possibly offer small benefits for connective tissue health. And for in terms of recovery and recovering from soreness after training, and training harder longer and more often, that may matter. Now there is some evidence that suggests that collagen will reduce muscle soreness and improve muscle strength 48 hours after bouts of exercise. But again, the impacts were modest, nothing dramatic, but maybe potentially useful. So, in terms of muscle, the takeaway is that collagen will not replace quality protein when it comes to muscle building and muscle protein synthesis. And it doesn't really stimulate muscle protein synthesis at all because it is deficient in tryptophan and low in essential amino acids. Now, but when you combine it with resistance training, maybe it may slightly improve body composition and recovery by supporting connective tissues. Now, if you're an Olympic athlete or you're competing at a high level, this may be important for you. But if you're taking collagen specifically for muscle building, you can stop it, you're wasting your money. But if you're taking it for supporting connective tissue, very, very small yet measurable improvement in the studies. Now, when someone comes to see me as a patient and asks me a tough question like, should I be taking collagen supplementation for joint, skin, or muscle? I need to be transparent and offer them an evidence-based answer. And it's not just, well, yes, it could help, or no, it doesn't work. That's not the answer that the science gives us. Now, there's still no major medical or nutritionist society that has formal guidelines that recommend collagen supplementations. And that's because the science is still very heterogeneous. They're different studies with different quality that are industry-biased and industry-funded. They have different doses, different formulations. The populations in different studies are different. Most of them are not randomized or controlled against placebo. And there's a lot of industry bias, especially in the skin research realm. Now, that doesn't mean that collagen is useless. It means that the certainty is from moderate to low. And science is about probabilities and not making promises that you're going to see a very important difference if you start taking collagen. I understand that my patients come from all walks of life, and not everyone has a hundred dollar per month budget to put on a supplement that will maybe gain pennies on the dollar, right? So here's my summary. For joint pain, it may modestly reduce pain, improve function for some people, but never see it as a cure, and it'll work best alongside strength training, movement, weight management, and other things that I'll talk about at the end. And for skin, high quality, independent research doesn't strongly support using collagen in terms of preventing wrinkles or improving skin aging. Skin health will far more be dependent on how are you eating, the quality of your overall nutrition, whether or not you protect yourself against the sun, whether or not you sleep well, and your smoking status. In terms of muscle and recovery, collagen cannot and should never replace complete protein. But as an add-on paired with resistance training, maybe it may support connective tissue adaptation and recovery. Now, in terms of safety, it's generally safe at the studied doses, but long-term data remains limited. We don't have studies showing people that are taking 20 grams of collagen every single day for 10 years and seeing what happens. And also the quality varies by product. We know that these supplements are rarely very well regulated, and sometimes the label contains things that are not supposed to be there, or the doses are incorrect. But the most important perspective is just that people who take collagen don't take it because they're uninformed. They take it because pain hurts. And because we've kind of modeled a society that despises aging and pain and loss of function. And there's always hope that we can take something that'll make us feel better about ourselves, but also maybe live a better life with less pain, right? There's nothing wrong with that. Good science isn't there to mock people who take supplements that have minimal evidence, and the absence of evidence is not evidence of absence of its effect. So some people will still say, I take collagen, I feel better, I can afford it, I like the taste, I like the texture in my smoothie or whatever you use it. But collagen is has to be seen as an add-on. The foundation is something a lot more important, right? It's having healthy joints because you're strong and there's healthy circulation and control inflammation and you control the movement quality of your exercises. So if you really want to protect your joints, they need to keep moving. Low impact and regular exercise will stimulate synovial fluid, which is the lubricant inside of your joint, which literally nourishes your cartilage. Now, walking, cycling, swimming, yoga, resistance training, they all help your joints stay lubricated and resilient. And here, motion is medicine and is probably a lot more effective, exponentially more important than taking collagen supplements. And strength training is like protecting your joints. The stronger your muscles are, they simply reduce the load on your joints. And that means less stress on your knees, on your hips, on your shoulders, with every step you take or lift that you make. Even just a few sessions a week can really meaningfully reduce joint pain. And if you support your joint by having strong muscles, that'll increase blood flow, reduce inflammation, and improve healing. And in terms of inflammation, eat to reduce your inflammation, not just for protein. Whole plant foods will bring polyphenols and antioxidants that target low-grade inflammation. Eating foods like berries and leafy greens, legumes, nuts and seeds, and adding spices like turmeric or ginger, they pro they matter more than any single supplement. And remember that sleep is your repair window. That's where the magic happens. Most tissue repair happens during your deep sleep stage. That's N3 slow wave deep sleep. I've talked about that a past episode, so go check out the episodes on sleep. You'll see that sleep is honestly your superpower when it comes to healing and recovery. Now, in terms of skin health, you need to feed your skin barrier from the inside out. Skin is the health of your skin is a reflection of hydration, circulation, and the amount of nutrients that your skin contains, not just what you apply topically on your skin. Now, don't forget that micronutrients like vitamin C, zinc, copper, and vitamin A are essential for your body's own collagen production. So taking collagen supplements, if you're not ingesting cofactors that are required to synthesize collagen is almost useless, right? Make sure that your diet is rich in all of these vitamins and minerals you need, and you'll find them in citrus, in peppers, and beans and seeds, in sweet potatoes, and in dark leafy greens. Now, no conversation about skin health would be complete without talking about the sun. The sun is like our phrenomie. It's good in moderation, it supports vitamin D production and circadian rhythms, but chronic overexposure breaks down collagen and makes your skin look older, more wrinkled, less elastic, you can develop sunspots. So make sure to protect yourself against overexposure to the sun. The last factor to consider when it comes to skin health is blood flow. Exercise, it increases circulation to the skin, it delivers oxygen, nutrients, and it actually helps clean out metabolic waste. So that post-workout glow is not cosmetic. It's expected to be there. Your skin looks healthier, younger if you are more active. Now, when it comes to muscle and recovery, the real growth in muscles happens after the workout. Now, muscles they don't grow during training, they grow during the recovery and rebuilding process. And progressive resistance training will always be better than supplementations. Now your body needs a reason to build tissue, and strength training provides the signal for muscle protein synthesis. And we I've seen different ratios thrown out in the scientific literature, but typically muscle protein synthesis is about 90% of the signal comes from weight training and about 10% from protein intake. And remember that collagen, as an incomplete protein that doesn't contain tryptophan and is low in essential amino acids like leucine, doesn't trigger muscle protein synthesis at all. And so do not rely on collagen if you're looking to build muscle. And just remember that total protein intake will matter a lot more than the type of protein that you're taking in. And meeting your daily protein needs from a mix of whole foods, it will outperform focusing on one specific amino acid or supplement. Now, when it comes to healthier skin, healthier joints, and healthier muscle, remember to not step over dollars to pick up pennies. In this case, collagen may be worth pennies, maybe a nickel, but a healthy plant-forward diet that's meeting your calorie needs and your protein needs is probably worth a buck or two. Same thing for exercise, sleep, and stress management. Now you can absolutely experiment with supplements if you want, but the biggest returns on your joints, your skin, and your physical performance will come with how you move and how you eat and sleep, and how you manage stress and how you consistently show up for your body. And that's the part that no supplement can replace. So if you're using collagen and it makes you feel better, that matters if you're considering it. Now you understand where the evidence supports its use, how strong it is, and where the evidence is weak. And if you choose not to use it, focus on whole foods, resistance training, sleep, and overall protein intake, that'll give you far greater returns and are dollars when compared to the pennies that come from collagen. So if you're approaching the end of the episode and you're like, well, he didn't really answer the question, should I take it or should I not? I'll be honest, I don't take it. I've never taken it, I don't expect on taking it or have any plans of starting it. I've competed the World Ninja Championships for three consecutive years, training 10 or more hours per week on a bad week, running hundreds of kilometers per month. I've been through pain, I've been through injury, I've never taken collagen. I don't expect on taking it, number one, because it's typically not a vegan-friendly supplement, and number two, because the science really doesn't convince me that there's really any significant benefit for the life that I'm living. Now, if I were in chronic pain from knee osteoarthritis and nothing else has worked, and I have an infinite budget for supplements, maybe I would try it for a few months. But honestly, I don't have any plans in the future of doing that. Right on. I hope this episode has helped clarify the science behind supplementing collagen. I'm not there to tell you whether to take it or not. Just if you do, keep in mind that the science surrounding it is quite weak and the benefits are quite modest. But that depends on your situation. There's for most people no harm in trying. Obviously, talk to your doctor or pharmacist before starting any new supplement regimen. Right on. Cool. Thanks for listening. Come back to see me in the next episode. We'll see you later. Hey everyone, go check out my website, plantbasedrjouels.com, to find free downloadable resources. And remember that you can find me on Facebook and Instagram at drjoulscormier and on YouTube at PlantbaseDr. Jewel.