My conclusion about Collagen for knee pain…
“After correcting as best as I could for the problems in the Coronado et al. meta-analysis, I concluded that there’s a 99% likelihood that a collagen supplement (10 grams daily for 10 weeks or so) would reduce my client’s knee pains. Further, my clients might hope for a reduction of their pain score by two points on the pain scale of zero to 10.
“I believe that a collagen supplement, in combination with knee exercises, stretches and massage, would be a winning strategy for many of my clients and, at the very least, would make them excellent candidates for a successful surgery and post-surgical rehab”.
Article contains useful information and pointers (with references) about nutrition for joint pain.
Introduction – a client-centered question
Some of my Pilates clients have sore knees and a degree of cartilage damage. My mat class exercises (developed and tweaked over 20 years) do seem to help them improve their pain and function. Physiotherapist Doug Kelsey has excellent advice, which has helped me heal clients’ knees through exercise and nutrition. But how about a nutritional supplement such as Collagen powder? Would it help improve their sore joints quickly or at least stop them from worsening while their exercise program improved their pain?
Meta-analysis of collagen supplements for knee pain
I found a 2018 meta-analysis by Coronado et al., which is useful but has some faults. These need to be understood and addressed when interpreting their analysis so that the remaining reliable information can shine forth.
Here are some of the problems with Coronado et al.-
a) Coronado et al. focus unduly on WOMAC questionnaire test scores, but these are not the best measure for assessing for any reduction in joint pain
WOMAC assesses the pain and function of the whole person rather than the pain and function of an individual knee joint. So if a test subject (without the researchers' knowledge) performs their own daily exercises and stretches and improves their overall function, then their WOMAC score will improve regardless of their supplement status, thereby invalidating the final results.
Researchers should instead use a test that specifically measures joint pain alone. The appropriate test for this is the VAS pain scale questionnaire, and fortunately, most of the researchers included this metric in their reports. Therefore, I was able to ignore the WOMAC scores and instead focus on the VAS pain scale reporting, and this gave me a much more consistent assessment of joint pain response to collagen supplementation.
· Example of WOMAC questionnaire here,
· History of WOMAC here, under the heading “Western Ontario and McMaster Universities Osteoarthritis Index”
Picture: The VAS score sheet enables the client to score their pain perception on a scale of zero to 10 (where zero equals no pain and 10 equals worst possible pain).
b) Coronado et al. compared two entirely different supplements in the one meta-analysis.
One study used a low dose of a collagen supplement called UC-II, which has a totally different biochemistry to that of Hydrolysed Collagen. I circumvented this by removing this study from the overall meta-analysis.
Picture:
A “UC-II” (undenatured type two collagen) supplement capsules (research shows that this may reduce auto-immune mediated arthritis)
Picture:
An example of a Hydrolised Collagen proteins supplement. The Collagen is derived from animal protein and has been broken down into easily digestible fragments. These fragments are easily absorbed and encourage collagen synthesis in skin, cartilage, and other connective tissues around the body. Note that today’s diet contains far less collagen than traditiona foods throuth the nineteenth and twentieth centuries. A good summary article of the benefits of collagen supplements is to be found here: Collagen and Gelatin Are Crucial for Optimal Health
c) The Coronado et al. meta-analysis quotes studies with potential conflicts of interest
The studies—many of which showed a joint benefit from Collagen supplementation—were funded by Collagen supplement manufacturers, which raises the risk of conflict of interest bias. The same applies (and more so) to patented medicine and vaccine trials where the financial stakes may be up to 1,000,000 times higher than for nutritional trials (Read: Covid-19: Researcher blows the whistle on data integrity issues in Pfizer’s vaccine trial).
At the end of the day, all we can do is be aware of the problem and, to some extent (and as much as common sense allows), trust the honesty of the researchers and the editors of the science journal.
d) An article that exposes other potential problems with the Coronado et al. analysis
Read about the problems here:-
Researching collagen to help his achy knees, a statistician explores the painfully weak evidence
What’s good about the Coronado et al. meta-analysis
The best thing about the Coronado et al. paper is that it uses only placebo-controlled studies. This reassures us that the patients’ pain reporting was accurate and not imaginary.
It also comments and confirms that Collagen supplements are very safe.
My conclusion about Collagen for knee pain
“After correcting as best as I could for the problems in the Coronado et al. paper, I concluded that there’s a 99% likelihood that a collagen supplement (10 grams daily for 10 weeks or so) would reduce my client’s knee pain. Further, my clients might hope for a reduction of their pain score by two points on the pain scale of zero to 10.
I believe that a collagen supplement, in combination with knee exercises, stretches and massage, would be a winning strategy for many of my clients and, at the very least, would make them excellent candidates for a successful surgery and post-surgical rehab.
Further reading: BMJ journal study of supplements for joint pain
Refer:-
BMJ study: Dietary supplements for treating osteoarthritis: a systematic review and meta-analysis
This huge and painstaking study (no pun intended) concludes that several supplements can reduce joint pain and even help repair joint cartilage (see chart and comments below).
Quote:
“The overall analysis, including all trials, showed that supplements provided moderate and clinically meaningful treatment effects on pain and function in patients with hand, hip or knee osteoarthritis in the short term, although the quality of evidence was very low. ”
My quick summary of Promising Joint Pain Nutritionals from the BMJ study:-
Curcumin reduced joint pain (95 to 98% probability over the short term - no long-term studies were found)
Undenatured collagen II and green-lipped mussel noticeably decreased pain in the medium-term (95 to 98% probability).
A list of potentially helpful supplements for joint pain and joint repair might include l-Carnitine, Pycnogenol, Boswellia (Myrrh), and Passion fruit extract.
Picture: BMJ study meta-analysis of nutritional supplements for joint pain
Further reading: a 28 references article on the biological benefits of collagen
Refer:
Collagen and Gelatin Are Crucial for Optimal Health
I included this article because it is hard to find by internet search and contains many references to original research.