Osteoarthritis can be incredibly frustrating. It makes total sense to be exploring any option that could help improve it. There are a lot of options that are proposed to help. Collagen supplementation, in various forms, is an option that has been promoted to help.
This post aims to cover the current research on the topic, while also exploring whether it is worth taking.
Understanding Osteoarthritis – Background to Understanding How Collagen Could Help
Osteoarthritis is defined as the degeneration of joint cartilage and the underlying bone.
It often causes pain and stiffness.
Cartilage is a tough, but smooth and slippery tissue which covers the surface of bones to help them move more freely against each other.
When this cartilage degenerates, the body undertakes repair processes in an attempt to change the structure of the joint in a way that allows people to continue moving without pain or stiffness.
Most people get osteoarthritis as they age, but not everybody gets pain.
Understanding what osteoarthritis is helps is useful background knowledge since it allows us to visualise how collagen may or may not theoretically help.
Since most people get the structural changes of osteoarthritis, but not everybody experiences symptoms, the definition of “help” should be focused on an improvement in pain and/or function.
How Could Collagen Theoretically Help?
There are a lot of ways that collagen has been proposed to help.
The most simplistic aspect is that cartilage is made up of collagen. Based on this, some people propose that consuming collagen could help.
There are a few aspects of how it could help beyond that though.
Helping Cartilage Repair or Delaying Cartilage Degradation
Starting with the simplistic aspect, potentially collagen could help with cartilage repair or delay the degradation of cartilage.
While some people claim that cartilage cannot be regrown after it has been lost, even that topic is debatable.
Whether or not regrowing cartilage is practical, at a minimum, either helping to repair it or delaying the degradation of it is likely a good thing.
Since cartilage is made up of collagen, supplementation could potentially help support it. There is also evidence that collagen peptides from supplementation does end up in cartilage too, which supports this mechanism a bit.
Helping Structures Around the Area
I have not seen a lot of other people talking about this topic in relation to collagen, but I have seen it in other areas.
A lot of people theorise that part of how exercise helps with osteoarthritis is by strengthening the supporting structures such as the muscles around the joint.
Collagen supplementation has evidence of helping with tendons and ligaments. Potentially strengthening those aspects could take some load off the painful area.
If this is the case, potentially collagen supplementation could help indirectly without even factoring in any benefit on cartilage.
Amino Acids vs Collagen Itself
A lot of the research is focused on the collagen peptides themselves.
When it comes to tendons and ligaments, my interpretation of the research is that it is actually more to do with the amino acid profile of collagen leading to the benefits for joint health.
Collagen peptides just so happen to be high in amino acids that most other protein sources are not high in.
Glycine is an example of one of these amino acids. There is research indicating that glycine itself could potentially help osteoarthritis. This research was not done in humans, but I am just using it as an example of the mechanism I am proposing.
We have also seen similar research showing glycine improving outcomes in tendinopathy.
The reason why this aspect is useful to be aware of is that when we go through the research, a lot of studies utilise collagen sources in dosages that have a low amount of amino acids.
If it was the collagen itself that mattered, this would be less of an issue. If the amino acid profile is important, then this really changes how we view the research.
What Does the Research Show?
I will start by looking at the current consensus based on systematic reviews on the topic.
There are three major relevant reviews of the research that I am aware of on this topic:
- 2012 Systematic Review
- 2018 Systematic Review – Similar to the 2012 one, just more recent.
- 2020 Review of the Evidence – This is the most comprehensive and relevant one.
All these reviews had similar findings and basically concluded that the research on collagen for osteoarthritis is promising, but there is insufficient evidence to make strong recommendations.
The benefits that were found were often quite small too.
While most of the research had small, positive findings, there were also some studies that had negative outcomes.
My personal interpretation of any adverse findings here is that it is less about collagen having any potential to be detrimental, and it is likely due to other explanations. When any supplement only has a small benefit, it would be rare to see ALL studies consistently finding that benefit, particularly with small sample sizes.
It is also worth noting that most of the research did not identify any structural change in the joints, even when pain and stiffness were improved. This downplays the idea that collagen is helping cartilage to regrow.
Flaws in the Research
There are obvious flaws in the research such as:
- Small sample sizes.
- Not enough studies.
- Not enough different dosages and different types of collagens have been used, due to the lack of studies.
- Potential for publication bias to be an issue. A lot of the research is industry-funded. It is not out of the realms of possibility that there was a bias towards publishing the studies that had more positive outcomes.
- Not a lot of research has looked at collagen alongside exercise programming targeted at improving pain and function.
Those are the obvious ones that most people could see.
Digging deeper though, an aspect of the research that confused me when I first looked at it many years ago was that a lot of studies used super low dosages of collagen.
For context, the consensus evidence-based dosage of collagen for tendon and ligament recovery after injury is 15-25g.
I personally never saw any studies on osteoarthritis using more than 10g of collagen. Maybe they exist and I missed them, but I am just highlighting that almost all the research has utilised a maximum of 10g.
All the research on undenatured type II used 10-40mg of collagen. Just to confirm that is milligrams whereas I previously mentioned grams.
This is because undenatured collagen is meant to be consumed in small amounts, whereas gelatin or hydrolysed collagen can be in higher amounts.
I mentioned the amino acids vs collagen peptides aspect earlier, since if the amino acid aspect was to be the sole reason collagen works, theoretically this makes the 10-40mg dosages useless. The amino acid profile would be too low to do anything.
For those who are curious though, some of the research using those low dosages had positive outcomes anyway.
A Theory on How We Could Get Even More Benefit Than the Research Shows
A gap I see in the research is a lack of higher dosage collagen being used.
While undenatured collagen would not be suitable for this, gelatin or hydrolysed collagen peptides could work well.
Research on tendons has measured the effects of 5g vs 10g vs 15g collagen. This research found 15g to be more effective than 5g or 10g.
Who’s to say that this is not the case in osteoarthritis as well?
Another aspect of the research on tendons is that collagen supplementation is proposed to be even more beneficial when timed 40-60 minutes prior to training/rehab sessions.
The timing is related to the amino acids peaking in the blood 40-60 minutes after consumption. Theoretically, this helps the tendons or ligaments absorb some more of the amino acids, as blood is flowing through that area during exercise.
Cartilage does not receive a lot of blood flow, so this mechanism makes less sense for osteoarthritis. But if the other theory of strengthening surrounding structures is relevant, then timing becomes relevant.
While it is not clear-cut that collagen supplementation DOES help osteoarthritis for sure, if it does, I would also wager that these variables could further improve outcomes.
Practical Interpretation of Whether Collagen is Worth Taking if you have Osteoarthritis
My interpretation is that collagen supplementation likely improves osteoarthritis outcomes a little bit.
If a decent amount larger-scale research comes out showing the opposite, I will change my thinking on this topic. I’ll also endeavour to come back and edit this article with updated research and interpretations.
While I believe it does improve outcomes a bit, I say that cautiously, since there is insufficient research to make strong claims. The benefit is likely relatively mild too and far less significant than other aspects such as exercise.
A lot of the research on collagen that has had positive outcomes has used varying dosages.
If I personally was going to take it for these purposes, I would have 15g of gelatin or hydrolysed collagen per day. On days that involve training/exercising the target area, I would aim to have it 40-60 minutes before the session. But I would not stress if the timing was off.
Whether or not it is worth taking depends on a few things:
- Are you willing to take something that might not actually help?
- Does it fit your budget well, factoring in that it might not help?
- Do you want to take it? The only real downside of having 15g+ of collagen is that some people do not like taking it. Some people might experience an upset stomach, although that is rare.
If you read that list and still want to take it with the understanding that it may or may not help a bit, then it makes sense to take it. If not, then it makes sense to focus on other options instead.