The Role of Vitamin C on Tendon Recovery

: On today's episode, the role of vitamin C on tendon recovery. Welcome to the podcast that gives you the most up to date, evidence based information on PHT rehab. My name is Brodie. I am an online physio, but I've also managed to overcome my own battle with PHT in the past. And now I've made it my mission to give you all the resources you need to overcome this condition yourself. So with that, let's dive into today's episode. Welcome back everyone. I have had a couple of research papers on vitamin C and tendinopathy and tendons and those sorts of things, um, come on my desk. And so I thought I'd create an episode about it. Um, I have in the past done a other episode, podcast episode on nutrition and tendon health, the title was the impact on nutrition on tendon health. If you wanted to, um, search that type that in and have a deeper listen, but I'll give you a bit of a rundown on that particular episode before we dive into these new ones that I've come across. Cause I do think it helps provide a little bit of context. Um, I have released it both on the. Overcoming PhD podcast as well as the run smarter podcast. So you can go find that, uh, if you would like, but like I say, that's the title. And we discussed a systematic review on that previous episode and the title of that paper, which is an open source paper, if you want to go check it out, is the impact of nutrition on tendon health and tendinopathy, a systematic review. And what we dive into on that episode, mainly talking about the concept of collagen synthesis. Tendons are primarily made up of collagen, which is just like a protein or like a tissue, you could call it and what happens similar to what happens in a muscle. it needs to break down in order to build up. And if we go into the gym and we do squats or deadlifts or bicep curls, we stress that particular tissue. It goes through this process, and the tendons themselves go through this process of collagen synthesis. They kind of break down and that is the necessary process in order to build up. And then when they do build up, they build up slightly stronger, then they do this. thing called adaptation and that's what we refer to when it comes to collagen synthesis or collagen turnover you might call it. That being very important when it comes to tendinopathies, when it comes to getting stronger, when it comes to running faster, all those things. This process is crucial. Anything that has been shown to inhibit this collagen synthesis is, you know, not advised when it comes to having a tendinopathy or preventing a tendinopathy. Anything that's been shown to enhance this process, we sort of wanna work our way towards. So this previous paper that I talked about, the hypothesis was that since, if we have collagen supplementation, because you can take collagen sort of supplements or tablets, that supplementation could be a plausible and potential strategy for healing tendons or just for tendon health in general. And also mentioned in that paper, that combining collagen, like if you take collagen supplements and combine that with vitamin C, it might have a net benefit or an enhanced benefit because vitamin C helps nutrition metabolism. And as we'll see in these other papers, it has some antioxidant properties and also helps directly with the collagen synthesis. So the paper that I talked about sort of mentioned alcohol and potential risk factors and the, that alcohol may potentially inhibit collagen synthesis. Studies have shown that, you know, a moderate consumption of alcohol does, seems to be correlated with, or be correlated as a risk factor for tendinopathies, but it also mentioned in that paper as well, it could be a proxy for other factors. So if someone is, a moderate alcohol consumer that there might also be something going on in their lives that also might create or not give you the right building blocks and might not give you the right process to go through collagen synthesis. But there's also some direct evidence or direct hypothesis that alcohol itself just creates a toxic environment within your body, which isn't a great thing. And they sort of concluded with collagen, collagen supplements, they may be helpful. But how you take it, the type of collagen supplements that you take, the dosage, like how strong or how much, the duration, how long do you take those collagen supplements for and the timing? Do you take it before your workouts, before your rehab or afterwards? All those sorts of things couldn't be concluded because of the variety amongst the studies. Um, there wasn't enough. consistency to provide clinical recommendations. So out of all the papers that they collected, there was just too much going on. There's too many variables. And it's like, okay, it may be helpful. We see this, we see this pattern. When they do take collagen, it does seem to be helpful, but just the recommendations, type dosage, duration, timing, all those sorts of things, we can't draw any conclusions there. So that's what I discussed about in the previous. So hopefully that sets the stage a bit of context and maybe a bit of a refresher because it has been some time since I did release that podcast episode. But I have two papers that I want to talk about today. One was slightly older, it's 2017. And the title is Vitamin C Enriched Gelatin Supplementation Before Intermittent Activity Augments Collagen Synthesis. Now... This paper doesn't talk about tendinopathy at all. It just talks about collagen synthesis, the process that it goes through and whether vitamin C enriched supplementation, they use a gelatin, they call it gelatin supplementation, whether just taking that and putting these people through a bout of exercise and following their blood work, what does that do for collagen synthesis? Does that enhance the process? Those sorts of things. So, I'll go through that now before I talk about the second one. Um, don't want to confuse you too much. So in their background abstract of this particular paper, I'll sort of talk about the hypothesis and that sort of stuff, they mentioned that, uh, nutritional and or exercise interventions that increase collagen synthesis and strengthen and strengthening of these tissues could have an important effect on injury rates. Like I say, this isn't talking about tendinopathy or people who already have tendinopathy is talking about people who exercise that just want to enhance that process by either getting stronger or preventing tendonopathies in the future. So we know that overload induces, you know, this tendon reaction, if you do it too much, you can get a tendonopathy. But with now we know collagen synthesis is really important. Nutrition is very important in that particular process. So that's why they say nutrition as like one pillar, and slash or exercise interventions is that other pillar. will have these important variables, will play important roles in collagen synthesis and therefore injury rates. And then I'm extrapolating that and saying therefore probably tendinopathy recovery and those sorts of things. So it was a small sample size in this particular study that had eight healthy male subjects and they completed a randomized double-blinded crossover design study in which all of these eight people I thought I could get through it, but I'm not going to get through it while Jasmine's barking so let's just wait for her to finish. As always, hasn't barked for several hours, but as soon as I hit record, something happens. Obviously she's going to start barking. Just the way the world works. Okay, so it was a double blinded trial. So the patients or the participants in this study were taking several different interventions. So one was a five gram vitamin C enriched. gelatin. One was a 15 gram so three times the amount and the other was just a placebo. So I'm guessing just a supplement that didn't have anything. So the subjects were blinded to this they didn't know which ones they were taking. But it's also a crossover design. So you know, every week or so they would then get another intervention which they didn't know which one it was. So after they initially drank it, they I'm guessing this gelatin is a fluid because they're talking about drinking. It was, they were taking blood measurements every 30 minutes to determine the amino acid content or an amino acid is just like a broken down protein. So they're looking at, um, collagen is also an amino acid, those sorts of things. Um, and I should, I should probably imagine like when I do these episodes. I start off by saying, look, I'm not a dietician. I'm not a nutritionist. I'm not qualified with talking about these sorts of things. But I do come across interesting studies that I want to highlight to you, I think is important to you in the context of this podcast. Um, and so like often when I'm reading these things, often when I'm trying to decipher these studies, I don't really know a lot of the technicalities. Um, but do want to try to get the hypothesis. The sort of results and discussion conclusions, all that sort of stuff across. But a lot of the stuff I read, I'm trying to make sense myself. So I should have said that at the start, but let's continue moving on. So they look at the amino acid concentration in their blood every 30 minutes after taking this, but they also did a bout of exercise in order to induce collagen synthesis. Let me just scroll down. So one hour after the initial supplementation, The subjects completed six minutes of jump rope or skipping rope to stimulate collagen synthesis. This pattern of supplementation was repeated three times per day with more than six hour between the exercise bouts for three days. Blood was drawn before and for 24, 48 and 72 hours after their first exercise bouts to determine the amino terminal propeptide of collagen one content. I'm just thinking that's just the amount of amino acids, the concentration floating around in the blood. They mentioned subjects who took 15 grams of gelatin one hour before exercise showed double the amino terminal propeptide of collagen one in their blood, indicating increased collagen synthesis. You'll have to take their word for it, that increases, or that's a sign of collagen synthesis, because I don't know too much about that. But in conclusion, they say that the data suggested that additional gelatin to an intermittent exercise program involves collagen synthesis, could play a beneficial role in injury prevention and tissue repair. So I think the key takeaway here is like, when we're talking about tendons, tendon rehab, we're not just talking about exercise. Well, we're not also just talking about nutrition, but nutrition plays a key role. I would say the other factors that we would put would be like your... psychosocial influences. We're talking about chronic pain, we're talking about, you know, pain in general has a social impact, also has a psychological impact. And for a lot of people, I've done success stories on this in the past. You might never get better, you might have the ideal nutrition, the ideal rehab protocol exercises. But if you have a lot of your pain that is psychosocially influenced, we need to address and have interventions for the social and the psychological triggers to then, you know, experience true healing. But, you know, I digress. The paper does have a couple of interesting points. While poor nutrition, genetics and disease can make connective tissue prone to failure, adequate recovery together with exercise normally improves function of the matrix. The result is a denser and stiffer tissue after training that is stronger. So obviously an ideal combination. They said that with work by, they reference a paper, Vera and colleagues who showed that, so they're talking about another paper now, that increasing glycine intake improves the mechanics of the Achilles tendon after injury, suggests that the nutritional intervention that increases amino acid components of collagen and a cofactor with vitamin C may improve collagen synthesis. So like I said, this is referring to another paper, this is actually in the introduction of this paper. They say that as a result of this background, in the current study, we used a randomized crossover design protocol to test the hypothesis that consuming gelatin, which is a food derivative of collagen, and vitamin C combined with exercise could increase collagen synthesis. Let's just pin a little bow on that one and move on to the next paper. So hopefully after reading that you're like, okay, maybe vitamin C enriched supplementation, those sorts of things can help collagen synthesis. I would say it's probably something that we wanna at least think about. Maybe even if you have your bloods done, maybe. a look at your vitamin C, see if you are vitamin C deficient, see if there are adequate amounts. If you are deficient, maybe we need to raise that up. If it is, probably at an adequate level, maybe we want to talk about raising up even further and seeing if that helps you with your recovery. Like I say, not a dietitian, not really advising too much here, just going through the research. The second paper that I had that I want to talk about is of a similar topic and is titled the effect of vitamin C on tendinopathy recovery, a scoping review. So while that previous paper, small sample size, but just looking at, you know, that turnover that collagen synthesis and seeing does supplementing with vitamin C gelatin, does that actually, you know, help with the process? But it's just a general population. This is actually looking at tendinopathy and tendinopathy a whole bunch of studies, a whole bunch of other systematic reviews and those sorts of things. But some of these studies are collected isn't just human studies, they also look at animal studies as well. So we do need to bear that in mind. Okay, in the abstract, they say the main molecular component of tendons is collagen, collagen one. And so that is 60 to 75% of the tendon, vast majority of that makeup of the tendon is collagen. They say collagen one. This study's aim was to critically evaluate the efficacy of vitamin C supplementation in the treatment of tendinopathies. At the same time, the study aims to determine the optimal conditions, including the dose and the time for vitamin C supplementation. Wouldn't that be nice if we can come up with, okay, is it effective? And if it is effective, this is how much you should take, and this is the time for you to take it to be most effective. In the introduction, they say, It has been described that vitamin C is important in tendon and ligament healing, mainly due to its antioxidant properties and its function as a cofactor for collagen synthesis. As a cofactor in collagen synthesis, vitamin C participates in, this is where it gets a little bit more complex, which kind of goes over my head a little bit, vitamin C participates in the hydroxylation of proline and lysine. I think the proline and lysine are just different proteins. And it converts to hydroxy proline and hydroxy lysine respectively in collagen molecules. This structural modification is instrumental for optimal mechanical tendon properties. I guess that's just describing how vitamin C actually helps in the collagen synthesis process. That's probably why I highlighted it, but it is a mouthful and it doesn't really. you know, goes over my head a little bit, like I said. They said a structured search was conducted. So they try to find all these studies with this trying to answer their question. And they came up with 16 articles. Well, they came up with 20 articles related to their descriptors, but 16 articles only met the inclusion criteria. Like I say, some of these papers included animals, some included humans, but let's see in the discussion what they talk about. The present report tries to bring some, some evidence that this micronutrient provided as a nutraceutical could play a role in tendon recovery post-injury. Results from animal models suggests the role of oxidative stress in tendon regeneration. In this context, oral administration of vitamin C was effective against rotator cuff degeneration. So they said that the papers that they found, some use the rotator cuff, which tendon, muscle tendon in the shoulder was effective when using vitamin C. However, other studies do not support the role of vitamin C in tendon recovery. Although a favorable effect of vitamin C was observed in the healing of the injured tendon in the rotator cuff, the difference was not significant in relation to control subjects. So you might have a look at people that have a tendinopathy in the shoulder, see how they go with vitamin C. Oh, they get better. But then you have a look at subjects that what looks like in the controller, don't know what was done in the control of that particular study, but they also showed improvement. Um, probably not to the X and the vitamin C group probably didn't show a significant improvement compared to the controls that would then suggest, Hey, this is a significant finding that we need to document. Therefore more research is necessary to solve these contradictory results, establishing the tendon condition. in which vitamin C exerts an optimal repair response. A point of potential interest concerns the recovery potential of vitamin C when combined with other compounds. Other studies showing that both vitamin C and hyaluronic acid have therapeutic effects on tendon healing, especially in the late phase of the tendon reparation. Other studies indicate that injection of ascorbic acid with T3 improves biological function of tenocytes favoring tendon healing. In a nutritional context, a supplement rich in gelatin and vitamin C, they said around 48 milligrams, increase the circulation levels of the amino acid compounds of collagen. Only one hour after consuming the supplement was enough. to increase collagen content. This looks familiar, this is like the paper that we just discussed, so they're probably talking about that. They say that other studies have used a food supplement based on mucopolysaccharides, type one collagen, and vitamin C, and studied the effect of three tendons, the Achilles, the patellar tendon, and the lateral epicondyle tendon, so your Achilles, your knee, and your elbow. The study provides evidence of the efficacy I think they mentioned a product here, Tino Tendo active, which I looked up. It looks like the it's T E N D O A C T I V E Tendo active. It seems like this is a product that has the that combination I talked about before. So the muco polysaccharides, the type one collagen and also vitamin C. I actually looked well, You can look that up yourself, but it seems like they use that in the particular study. And they said that they observed a 69% reduction in pain in patients with Achilles tendinopathy and 83% in patients with tennis elbow and a 75% reduction in pain in patients with a supraspinatus tendinopathy. So tendinopathy in the rotator cuff, in the shoulder. This was associated with clear structural improvements, including a reduction in the thickness of the affected tendon. similar results were found by supplementing by supplementation with mucopolysaccharides, type 1 collagen and vitamin c combined with a passive stretching program, which is just another one that they found. So I'll talk about the conclusion in a second, but it seems like with these results, it seems like just taking vitamin C doesn't seem to be that helpful when compared looking at studies, looking at the rotator cuff, but in combination with other things, in combination with other nutrients, seems to have some effect. Conclusions. In view of the studies analyzed, it seems clear the usefulness of vitamin C in the therapeutic approaches to tendinopathies. A supplementation of vitamin C alone or combined with other compounds increases the production of collagen. with the consequent improvement of recovery in the patient. It is important to consider that many of the studies have been developed for injectable administration of vitamin C in the affected area. So they're injecting. In addition, vitamin C deficiency is fundamentally associated with a decrease in pro-collagen synthesis and reduced hydroxylation of proline and lysine residuals. hindering the tendon repair process. Okay, they're just talking about if you have a deficiency in vitamin C, it can hinder the tendon repair process. Despite this, there is no consensus on the more efficient dosage to be used. At the moment, 60 milligrams of vitamin C alone or in combination with other compounds seems to be the dose mainly proposed for tendinopathy treatment. Nonetheless, when vitamin C is taken alone as an antioxidant, higher doses have been used. Therefore, more studies have to be carried out to determine the optimal oral dose that could be useful in the resolution of this pathology. Finally, the present report is focused only on vitamin C, but nutrition in general and exercise have to be considered together for optimal and healthy performance. I think that sums things up quite well. It needs to be a factor. I think it needs to be just one area to consider an important area to consider when factoring in going through rehab or even preventing tendinopathies or increasing performance. I know preparing for a December high rocks race that I'm you know, training for I am breaking down my body a lot. doing like high explosive movements, a lot of strength training, a lot of running. And therefore I have put an invest a lot of time in protein, building up protein, getting the right amino acids trying to get the right sort of stuff. So I'm not as sore, but I'm also recovering a lot quicker. So that's from a performance standpoint. But I think we need to take the same approach from a rehab standpoint as well. Let me do the right things, build up my body, get the right dosage of exercises, get the right exercises in general, but then also the right sets, reps, weights. Let me try to trigger this adaptation process, but then let me give myself the building blocks to help that process along that will generate some, that will compound using those different areas of focus and lead to more and more momentum. If we go in the other direction, say, let me just do the exercises, but if I eat poorly, if I sleep poorly, if I don't give myself the necessary building blocks. On the opposite side, if I have a lot of sugar or if I have a lot of alcohol that inhibits the process, don't expect the same results. I think this is a good, like I wanna do nutrition episodes out there to keep people thinking about these sort of things. I know this doesn't have very clear practical guidance to say everyone should take vitamin C with these particular things. It has to be this dosage, it has to be this. We conclude with this paper saying, you know, more research needs to be conducted. But I think suffice to say, let's start thinking about this and let's start making slight changes. If you do want to try vitamin C, or even if you just want to get your vitamin C levels measured just to see if you are deficient or at optimal levels, then let's have that discussion. Let's open that discussion, start looking at more elements for your recovery. I hope you found this useful. Like I said, it's tough for me. I do enjoy talking about these topics without being qualified and trying to sort of dance around being, just trying to talk about what this study shows without me being too proficient in it myself. But nonetheless, hope you found it useful. Thank you for listening. We'll catch you next time. If you are looking for more PhD resources, then check out my website link in the show notes. There you will find my free PhD five day course, other online content and ways you can. personally connect with me, including a free 20 minute injury chat to discuss your current rehab and any tweaks you might need to make. Well done for taking an active role in your rehab by listening to content like this, and together we can start ticking off all of your rehab goals and finally overcome your PHT.