Study analysis · British Journal of Sports Medicine · 2017
69 trials, 20 supplements, and a billion-dollar question: Do ANY of them actually fix osteoarthritis pain?
A huge review found some supplements may help arthritis pain briefly, but the evidence is weak and nothing clearly works long-term.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
In simple terms
This is a study where scientists collected many experiments where people with sore joints took supplements or a fake pill. They put all the results together to see if supplements help. The findings suggest some supplements might help a little bit for a short time, but the experiments were not perfect, so we can't be sure that supplements actually cure joint pain.
What’s the bottom line?
Researchers combined 69 randomized trials of 20 oral supplements for hand, hip, or knee osteoarthritis. They looked at whether supplements reduced pain, improved function, changed joint structure, and caused side effects compared with placebo.
How strong is this study?
This is a very thorough study that looked at all the best experiments on joint supplements, which is a good start. But the original experiments often had problems—like too few people or not lasting long enough—so the quality of the evidence is not very strong. That means we should not trust the results completely, even though it was carefully done.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
0 / 100
- Randomizationnot randomized
- Blindingblinding unclear
- Control groupno control group
- Sample sizeno sample size reported
- Follow-upno follow-up reported
100 / 100
77 / 100
- P-values+15/15
- Effect size+20/20
- Confidence intervals+15/15
- Pre-registrationnot pre-registered
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 539 / 100
Probability of being correct
The highest quality evidence. Systematic reviews and meta-analyses that pool randomized controlled trials, giving the most reliable summary of experimental evidence.
This design can establish causation. The systematic review aggregates RCTs, which can establish causation, but the overall quality of included trials was very low for many supplements. Therefore, causal claims should be tempered with uncertainty about the true magnitude and duration of effects.
No Conflicts
No conflicts of interest identified
No conflicts of interest or funding declarations were present in the provided text. All identified authors have academic affiliations.
The text contains multiple abstracts (S292, 462-464) from a conference. No COI or funding statements were included in the provided excerpts.
Key takeaways
- 01
Seven supplements (collagen hydrolysate, passion fruit peel extract, Curcuma longa extract, Boswellia serrata extract, curcumin, pycnogenol, and L-carnitine) showed large short-term pain reductions with an effect size greater than 0.80, but the evidence was very low quality.
- 02
Six others (including glucosamine and chondroitin) had statistically significant pain improvements, but these were small or of unclear clinical importance.
- 03
Chondroitin had a small structural improvement (effect size −0.30, 95% CI −0.42 to −0.17) that was statistically significant but not clinically important.
- 04
No supplement showed clinically important long-term pain relief.
- 05
Absolute risk differences, such as extra cases per 1,000 people, were not reported.
- 06
This study could not calculate absolute benefits like 'X extra people per 1,000 improved' because the outcomes are pain and function scores, not events.
- 07
So we cannot say how many people would notice a meaningful difference.
- 08
The short-term benefits for some supplements may be real, but confidence is very low.
- 09
Glucosamine and chondroitin, which are widely used, probably do not provide meaningful pain relief.
- 10
No supplement clearly helps long-term.
Surprising findings
- Seven supplements showed large short-term pain reductions (SMD >0.80), but the evidence was rated very low quality.Large effects usually come from higher-quality trials. Here, large effects came from small, flawed trials, suggesting possible exaggeration.
- Glucosamine and chondroitin, the most widely used supplements, were ineffective or clinically unimportant for pain.These are the household names for joint health. Many people believe they work, but this meta-analysis says the benefit is too small to matter.
- No supplement showed clinically important long-term pain relief.You'd expect at least one supplement to maintain benefits beyond a year, but none did.
Practical takeaways
If you take glucosamine or chondroitin for osteoarthritis pain, reconsider the cost and expectation—this review suggests the benefit is too small to notice.
Evidence quality is low, and some people may still experience placebo or individual benefit. Talk to your doctor before stopping any treatment.
medium confidenceIf you want to try a supplement, consider discussing a short-term trial (e.g., 4–12 weeks) with your clinician and track pain/function objectively.
Only two supplements (green-lipped mussel and undenatured type II collagen) had medium-term clinically important effects, and those findings are based on limited studies. Absolute benefit is unknown.
low confidenceAvoid diacerein unless prescribed and monitored, due to higher adverse events, especially diarrhea.
This is based on meta-analysis, not a head-to-head trial; absolute risk increase was not reported.
medium confidenceWhy this study matters
Seven supplements showed big short-term pain effects—but the evidence is flimsy
In 69 randomized trials of 20 oral supplements, seven—collagen hydrolysate, passion fruit peel extract, Curcuma longa extract, Boswellia serrata extract, curcumin, pycnogenol, and L-carnitine—had large short-term pain reductions with a standardized mean difference (SMD) >0.80, which is a relative/standardized effect, not an absolute risk difference. However, these findings came from a limited number of small trials and were rated very low quality. Absolute benefit (e.g., how many extra people per 1,000 improved) was not reported because outcomes were continuous symptom scores.
People spend billions on joint supplements. This says a few might work short-term, but you can't trust the size of the effect yet.
Glucosamine and chondroitin are probably not worth it for pain
Glucosamine and chondroitin, the most popular osteoarthritis supplements, produced small statistically significant pain reductions that were judged clinically unimportant. The review says they are 'either ineffective or showed small and arguably clinically unimportant treatment effects.' Absolute risk differences were not reported, so we can't say how many people would notice a meaningful difference.
Millions of people take glucosamine/chondroitin daily. This suggests the benefit is too small to matter in real life.
No supplement showed clinically important long-term pain relief
Across all 20 supplements, none demonstrated clinically important pain reduction at long-term follow-up (generally more than 12 months). Short-term benefits did not translate into lasting relief. Absolute long-term risk differences were not reported.
If you're looking for a supplement to manage arthritis for years, this review offers little hope.
Only two supplements helped at medium term—green-lipped mussel and undenatured type II collagen
At medium-term follow-up (typically 6–12 months), only green-lipped mussel extract and undenatured type II collagen had clinically important pain effects. Most other supplements either lost effectiveness or had unclear clinical importance. The number of studies was limited, and evidence quality varied.
These are less famous than glucosamine, so it's a surprising twist for supplement shoppers.
Chondroitin slightly slows joint space narrowing—but it's not clinically meaningful
Chondroitin showed a statistically significant structural improvement in knee osteoarthritis with an SMD of −0.30 (95% CI −0.42 to −0.17). That is a relative/standardized effect, not an absolute risk reduction, and the review judged it not clinically important. It may not translate into less pain or better function.
Structural changes sound impressive, but if patients don't feel better, it's a marketing angle rather than a real benefit.
Diacerein is the safety outlier—more adverse events, especially diarrhea
Most supplements had safety profiles similar to placebo, but diacerein was associated with more adverse events, particularly diarrhea. This safety signal may limit its usefulness even if it has some pain benefit. Absolute risk increases were not reported.
Natural doesn't always mean harmless. This is a concrete example of a supplement with a real downside.
Want the whole report?
Detailed mode opens the full scientific breakdown — every score component, the methodology, conflicts of interest, the evidence analysis behind each claim, and the raw study data.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Researchers combined 69 randomized trials of 20 oral supplements for hand, hip, or knee osteoarthritis. They looked at whether supplements reduced pain, improved function, changed joint structure, and caused side effects compared with placebo.
Research results
Seven supplements (collagen hydrolysate, passion fruit peel extract, Curcuma longa extract, Boswellia serrata extract, curcumin, pycnogenol, and L-carnitine) showed large short-term pain reductions with an effect size greater than 0.80, but the evidence was very low quality. Six others (including glucosamine and chondroitin) had statistically significant pain improvements, but these were small or of unclear clinical importance. Chondroitin had a small structural improvement (effect size −0.30, 95% CI −0.42 to −0.17) that was statistically significant but not clinically important. No supplement showed clinically important long-term pain relief. Absolute risk differences, such as extra cases per 1,000 people, were not reported.
What this means - more context
This study could not calculate absolute benefits like 'X extra people per 1,000 improved' because the outcomes are pain and function scores, not events. So we cannot say how many people would notice a meaningful difference. The short-term benefits for some supplements may be real, but confidence is very low. Glucosamine and chondroitin, which are widely used, probably do not provide meaningful pain relief. No supplement clearly helps long-term.
To investigate the efficacy and safety of oral dietary supplements for patients with hand, hip, or knee osteoarthritis.
Systematic review and random-effects meta-analysis of 69 randomized controlled trials testing 20 oral dietary supplements versus placebo in hand, hip, or knee osteoarthritis. Seven supplements (collagen hydrolysate, passion fruit peel extract, Curcuma longa extract, Boswellia serrata extract, curcumin, pycnogenol, L-carnitine) showed large short-term pain reductions (effect size >0.80) but from limited small trials and very low-quality evidence. Glucosamine and chondroitin produced small, statistically significant but clinically unimportant pain reductions. No supplement showed clinically important long-term pain relief. Chondroitin had small structural improvement (effect size −0.30, 95% CI −0.42 to −0.17) that was not clinically important. Safety was similar to placebo except diacerein, which had more adverse events. Overall evidence quality ranged from very low to high, but key supplement findings were very low quality.
Methods Used
Systematic review with random-effects meta-analysis and meta-regression. Searched MEDLINE, EMBASE, Cochrane Register of Controlled Trials, Allied and Complementary Medicine, and CINAHL from inception to April 2017. Included randomized controlled trials comparing oral supplements with placebo for hand, hip, or knee osteoarthritis. Assessed pain, physical function, joint structure, and safety. Evidence quality graded using GRADE.
Main Finding
In adults with hand, hip, or knee osteoarthritis, oral dietary supplements as a group produced moderate, clinically meaningful short-term improvements in pain and physical function compared with placebo, but the quality of evidence was very low. Seven supplements showed large short-term pain effects (effect size >0.80), another six had statistically significant but clinically unclear pain effects, and only green-lipped mussel extract and undenatured type II collagen showed clinically important medium-term pain effects. No supplement showed clinically important long-term pain reduction. Chondroitin had a small structural improvement (effect size −0.30, 95% CI −0.42 to −0.17) that was statistically significant but not clinically important. Absolute risk differences were not reported because outcomes were continuous symptom scores, not disease events.
Confidence Level
No retraction or corrections noted. The review methods are robust, but confidence in most supplement-specific conclusions is limited by very low quality evidence, small trials, methodological flaws, and heterogeneity. Long-term data are sparse and do not support clinically important benefits.
Study Flags
Red Flags
- •Very low quality evidence for most supplement comparisons
- •Many included trials were small and had methodological flaws
- •No clinically important long-term benefits were found, and absolute risk differences were not reported
Surprising Findings
Seven supplements showed large short-term pain reductions (SMD >0.80), but the evidence was rated very low quality.
Large effects usually come from higher-quality trials. Here, large effects came from small, flawed trials, suggesting possible exaggeration.
Practical Takeaways
If you take glucosamine or chondroitin for osteoarthritis pain, reconsider the cost and expectation—this review suggests the benefit is too small to notice.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 539 / 100
Probability of being correct
The highest quality evidence. Systematic reviews and meta-analyses that pool randomized controlled trials, giving the most reliable summary of experimental evidence.
Human Meta-Analysis
Subject
Lower probability
on the GRADE evidence scale
This is a study where scientists collected many experiments where people with sore joints took supplements or a fake pill. They put all the results together to see if supplements help. The findings suggest some supplements might help a little bit for a short time, but the experiments were not perfect, so we can't be sure that supplements actually cure joint pain.
The study has a COI section but no disclosure was found. A small penalty has been applied.
Strengths
- Systematic search of multiple databases (MEDLINE, EMBASE, Cochrane, etc.)
- Random-effects meta-analysis used to account for heterogeneity
- Included only randomized controlled trials
Weaknesses
- Quality of evidence was very low for many comparisons
- Substantial heterogeneity across studies
- Many supplements had few trials and small sample sizes
Methodology
Evidence Keywords
Statistical Reporting
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Researchers combined 69 randomized trials of 20 oral supplements for hand, hip, or knee osteoarthritis. They looked at whether supplements reduced pain, improved function, changed joint structure, and caused side effects compared with placebo.
Research results
Seven supplements (collagen hydrolysate, passion fruit peel extract, Curcuma longa extract, Boswellia serrata extract, curcumin, pycnogenol, and L-carnitine) showed large short-term pain reductions with an effect size greater than 0.80, but the evidence was very low quality. Six others (including glucosamine and chondroitin) had statistically significant pain improvements, but these were small or of unclear clinical importance. Chondroitin had a small structural improvement (effect size −0.30, 95% CI −0.42 to −0.17) that was statistically significant but not clinically important. No supplement showed clinically important long-term pain relief. Absolute risk differences, such as extra cases per 1,000 people, were not reported.
What this means - more context
This study could not calculate absolute benefits like 'X extra people per 1,000 improved' because the outcomes are pain and function scores, not events. So we cannot say how many people would notice a meaningful difference. The short-term benefits for some supplements may be real, but confidence is very low. Glucosamine and chondroitin, which are widely used, probably do not provide meaningful pain relief. No supplement clearly helps long-term.
To investigate the efficacy and safety of oral dietary supplements for patients with hand, hip, or knee osteoarthritis.
Systematic review and random-effects meta-analysis of 69 randomized controlled trials testing 20 oral dietary supplements versus placebo in hand, hip, or knee osteoarthritis. Seven supplements (collagen hydrolysate, passion fruit peel extract, Curcuma longa extract, Boswellia serrata extract, curcumin, pycnogenol, L-carnitine) showed large short-term pain reductions (effect size >0.80) but from limited small trials and very low-quality evidence. Glucosamine and chondroitin produced small, statistically significant but clinically unimportant pain reductions. No supplement showed clinically important long-term pain relief. Chondroitin had small structural improvement (effect size −0.30, 95% CI −0.42 to −0.17) that was not clinically important. Safety was similar to placebo except diacerein, which had more adverse events. Overall evidence quality ranged from very low to high, but key supplement findings were very low quality.
Methods Used
Systematic review with random-effects meta-analysis and meta-regression. Searched MEDLINE, EMBASE, Cochrane Register of Controlled Trials, Allied and Complementary Medicine, and CINAHL from inception to April 2017. Included randomized controlled trials comparing oral supplements with placebo for hand, hip, or knee osteoarthritis. Assessed pain, physical function, joint structure, and safety. Evidence quality graded using GRADE.
Main Finding
In adults with hand, hip, or knee osteoarthritis, oral dietary supplements as a group produced moderate, clinically meaningful short-term improvements in pain and physical function compared with placebo, but the quality of evidence was very low. Seven supplements showed large short-term pain effects (effect size >0.80), another six had statistically significant but clinically unclear pain effects, and only green-lipped mussel extract and undenatured type II collagen showed clinically important medium-term pain effects. No supplement showed clinically important long-term pain reduction. Chondroitin had a small structural improvement (effect size −0.30, 95% CI −0.42 to −0.17) that was statistically significant but not clinically important. Absolute risk differences were not reported because outcomes were continuous symptom scores, not disease events.
Confidence Level
No retraction or corrections noted. The review methods are robust, but confidence in most supplement-specific conclusions is limited by very low quality evidence, small trials, methodological flaws, and heterogeneity. Long-term data are sparse and do not support clinically important benefits.
Study Flags
Red Flags
- •Very low quality evidence for most supplement comparisons
- •Many included trials were small and had methodological flaws
- •No clinically important long-term benefits were found, and absolute risk differences were not reported
Surprising Findings
Seven supplements showed large short-term pain reductions (SMD >0.80), but the evidence was rated very low quality.
Large effects usually come from higher-quality trials. Here, large effects came from small, flawed trials, suggesting possible exaggeration.
Practical Takeaways
If you take glucosamine or chondroitin for osteoarthritis pain, reconsider the cost and expectation—this review suggests the benefit is too small to notice.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 539 / 100
Probability of being correct
The highest quality evidence. Systematic reviews and meta-analyses that pool randomized controlled trials, giving the most reliable summary of experimental evidence.
Human Meta-Analysis
Subject
Lower probability
on the GRADE evidence scale
This is a study where scientists collected many experiments where people with sore joints took supplements or a fake pill. They put all the results together to see if supplements help. The findings suggest some supplements might help a little bit for a short time, but the experiments were not perfect, so we can't be sure that supplements actually cure joint pain.
The study has a COI section but no disclosure was found. A small penalty has been applied.
Strengths
- Systematic search of multiple databases (MEDLINE, EMBASE, Cochrane, etc.)
- Random-effects meta-analysis used to account for heterogeneity
- Included only randomized controlled trials
Weaknesses
- Quality of evidence was very low for many comparisons
- Substantial heterogeneity across studies
- Many supplements had few trials and small sample sizes
Methodology
Evidence Keywords
Statistical Reporting
Scoring
How strong is this study?
This is a very thorough study that looked at all the best experiments on joint supplements, which is a good start. But the original experiments often had problems—like too few people or not lasting long enough—so the quality of the evidence is not very strong. That means we should not trust the results completely, even though it was carefully done.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
0 / 100
- Randomizationnot randomized
- Blindingblinding unclear
- Control groupno control group
- Sample sizeno sample size reported
- Follow-upno follow-up reported
100 / 100
77 / 100
- P-values+15/15
- Effect size+20/20
- Confidence intervals+15/15
- Pre-registrationnot pre-registered
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 539 / 100
Probability of being correct
The highest quality evidence. Systematic reviews and meta-analyses that pool randomized controlled trials, giving the most reliable summary of experimental evidence.
This design can establish causation. The systematic review aggregates RCTs, which can establish causation, but the overall quality of included trials was very low for many supplements. Therefore, causal claims should be tempered with uncertainty about the true magnitude and duration of effects.
No Conflicts
No conflicts of interest identified
No conflicts of interest or funding declarations were present in the provided text. All identified authors have academic affiliations.
The text contains multiple abstracts (S292, 462-464) from a conference. No COI or funding statements were included in the provided excerpts.
Standing
The people behind it
The researchers who wrote the study this analysis is built on.
Authored by
5 researchersIf this is your work, this is how we attribute it on Fit Body Science. Xiaoqian Liu is listed as the lead author.