Osteoarthritis & Joints
A fixed time to noticeable changes cannot be derived from the studies: they measured pain scores in knee osteoarthritis after 4 to 8 weeks [1][3][4], and in rheumatoid arthritis in a pilot study after 8 weeks [5]. The evidence is limited [6][8].
- Measurement periods: 4 to 8 weeks in the studies [1][3][4]
- Ibuprofen comparison: 4 weeks, 1,500 mg extract vs. 1,200 mg ibuprofen [1]
- Rheumatoid arthritis: pilot study, 8 weeks, 45 people [5]
- Meta-analysis (Daily 2016): 8 studies, evidence insufficient according to the authors [6]
- Study doses: about 1,000-1,500 mg curcumin per day [3][2][6]
- EFSA 2017: cause-and-effect relationship not established [8]
What's behind it
A fixed "time to effect" cannot be read from the literature. Studies set a duration in advance (for example 4, 6 or 8 weeks) and measure pain or function scores at defined time points. When something changes in an individual person was usually not the study objective. The figures below therefore describe measurement periods, not a guaranteed point in time.
What the sources show
Knee osteoarthritis, 4 weeks: In a study of 367 people, participants received either 1,200 mg ibuprofen or 1,500 mg Curcuma domestica extract per day for 4 weeks (each capsule calculated to contain 250 mg curcuminoids). WOMAC scores were improved in both groups after 2 and after 4 weeks compared with baseline. For the total, pain and function scores the extract was not inferior to ibuprofen at week 4; for stiffness only a trend was seen [1]. In an open-label study (139 people, 28 days), pain (VAS) and KOOS score were similar on day 14 and day 28 with 3 × 500 mg curcumin (BCM-95) and with diclofenac (2 × 50 mg) [2].
Knee osteoarthritis, 6 to 8 weeks: In 40 people with mild to moderate knee osteoarthritis, WOMAC, VAS and LPFI scores fell more under 1,500 mg curcuminoids per day than under placebo after 6 weeks; pain and function improved, stiffness did not [3]. In an 8-week placebo-controlled study of 101 adults (2 × 500 mg curcumin extract), the KOOS knee pain score and pain ratings fell more than under placebo; pain-relieving medication was reduced in 37% of the curcumin group and 13% of the placebo group [4].
Rheumatoid arthritis: A pilot study of 45 people compared 500 mg curcumin, 50 mg diclofenac and both together. The disease activity score DAS28 improved in all three groups, most clearly in the curcumin group [5]. The study is small; the 8-week observation period comes from secondary reports, not from the freely accessible abstract.
Overall picture: A meta-analysis of 8 randomized trials found lower WOMAC and VAS scores with turmeric extracts providing about 1,000 mg curcumin per day. The authors consider the number, sample size and quality of the studies insufficient for definitive conclusions [6].
What this means in practice
The studies measure after 4 to 8 weeks. From this you cannot predict whether or when you will notice anything yourself. On absorption: in a crossover study in healthy volunteers (single dose), curcuminoid uptake into the blood ranged from 1.3-fold to 45.9-fold that of an unformulated standard, depending on the formulation [7]. Whether better absorption also leads to earlier changes in joint complaints was not examined there.
Limits of this statement
In 2017 EFSA could not establish a cause-and-effect relationship between curcumin and maintenance of joint function; no conclusions could be drawn from the submitted human studies [8]. The studies differ in preparation, dose and duration, are partly small or open-label, and concern osteoarthritis and rheumatoid arthritis, which are two different diseases. This answer does not replace medical advice; joint complaints belong in medical hands (for arthritis, e.g. rheumatology). Do not change medication without consulting your doctor.
Common follow-up questions
The studies do not establish a fixed point in time when effects set in. In a study of 367 patients with knee osteoarthritis, WOMAC scores improved from baseline after just 4 weeks on 1,500 mg Curcuma extract per day (Kuptniratsaikul et al., 2014) DOI. In a smaller trial (n = 40) with 1,500 mg curcuminoids per day, an advantage over placebo was measured after 6 weeks (Panahi et al., 2014) DOI. Response varies from person to person.
It is not established that a more bioavailable formulation relieves joint complaints faster. Formulations mainly raise curcuminoid levels in the blood: in a study in healthy volunteers they appeared 45.9-fold higher with one formulation than with unformulated curcumin (Jäger et al., 2014) DOI. As to duration: a pilot trial in 40 people with mild-to-moderate knee osteoarthritis (1,500 mg curcuminoids per day) compared symptom scores against placebo over 6 weeks (Panahi et al., 2014) DOI. Always discuss joint complaints with your doctor.
Curcumin is poorly absorbed, rapidly metabolised and quickly eliminated from the body (Anand et al., 2007) DOI. Approaches to increase absorption include piperine, liposomes and phospholipid complexes (Anand et al., 2007) DOI. In a crossover study in healthy volunteers, curcuminoid absorption was 1.3- to 45.9-fold higher than with unformulated curcumin, depending on the formulation (Jäger et al., 2014) DOI.
There is little data on this. In a small pilot trial of 45 patients with active rheumatoid arthritis, groups received 500 mg curcumin, 50 mg diclofenac or both; disease scores improved in all three groups, and curcumin treatment was not linked to adverse events (Chandran & Goel, 2012) DOI. In the laboratory, a curcuminoid extract inhibited several drug-metabolising enzymes (Volak et al., 2008) DOI. Talk to your doctor before combining it with medication.
Read more
Want to dive deeper into the subject? Continue here:
- Safety check: The full safety profile and detailed information on possible side effects.
- Effects guide: Learn more about the broad range of applications of turmeric and what the studies show.
- Bioavailability: Understand the mechanisms of absorption and why formulations differ.
References
- [1] Kuptniratsaikul, V. et al. (2014). Efficacy and safety of Curcuma domestica extracts compared with ibuprofen in patients with knee osteoarthritis: a multicenter study. Clinical Interventions in Aging. DOI: 10.2147/CIA.S58535
- [2] Shep, D. et al. (2019). Safety and efficacy of curcumin versus diclofenac in knee osteoarthritis: a randomized open-label parallel-arm study. Trials. DOI: 10.1186/s13063-019-3327-2
- [3] Panahi, Y. et al. (2014). Curcuminoid Treatment for Knee Osteoarthritis: A Randomized Double-Blind Placebo-Controlled Trial. Phytotherapy Research. DOI: 10.1002/ptr.5174
- [4] Lopresti, A. L. et al. (2021). An Investigation into the Effects of a Curcumin Extract (Curcugen®) on Osteoarthritis Pain of the Knee: A Randomised, Double-Blind, Placebo-Controlled Study. Nutrients. DOI: 10.3390/nu14010041
- [5] Chandran, B. & Goel, A. (2012). A Randomized, Pilot Study to Assess the Efficacy and Safety of Curcumin in Patients with Active Rheumatoid Arthritis. Phytotherapy Research. DOI: 10.1002/ptr.4639
- [6] Daily, J. W. et al. (2016). Efficacy of Turmeric Extracts and Curcumin for Alleviating the Symptoms of Joint Arthritis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. Journal of Medicinal Food. DOI: 10.1089/jmf.2016.3705
- [7] Jäger, R. et al. (2014). Comparative absorption of curcumin formulations. Nutrition Journal. DOI: 10.1186/1475-2891-13-11
- [8] EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) (2017). Curcumin and normal functioning of joints: evaluation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006. EFSA Journal. DOI: 10.2903/j.efsa.2017.4774
In knee osteoarthritis studies, pain and function scores changed under 1,500 mg Curcuma extract over 4 weeks similarly to under 1,200 mg ibuprofen [2]. The evidence is limited, and EFSA saw no established cause-and-effect link for joint function [6][8].
- 367 people (Kuptniratsaikul 2014): 1,500 mg extract vs. 1,200 mg ibuprofen, 4 weeks, WOMAC [2]
- 139 people (Shep 2019): 1,500 mg BCM-95 vs. diclofenac, 28 days, open-label [3]
- 40 people (Panahi 2014): 1,500 mg curcuminoids, 6 weeks, vs. placebo [4]
- 101 people (Lopresti 2021): Curcugen®, 8 weeks, pain medication reduced in 37% vs. 13% [5]
- Meta-analyses: evidence not adequate for recommendations according to the authors [6][7]
- EFSA 2017: cause-and-effect relationship not established [8]
What's behind it
Knee osteoarthritis (gonarthrosis) is a chronic degenerative joint disease. Studies usually record symptoms with the WOMAC index (pain, stiffness, function), pain scales (VAS) or the KOOS. In the laboratory, curcumin together with resveratrol inhibited activation of the inflammatory switch NF-κB and the formation of gene products such as COX-2, MMP-3 and MMP-9 in human cartilage cells stimulated with interleukin-1β [1]. These are cell experiments, not proof of efficacy in humans.
What the sources show
Comparison with ibuprofen: 367 people with knee osteoarthritis received 1,200 mg ibuprofen or 1,500 mg Curcuma domestica extract per day for 4 weeks. WOMAC scores improved in both groups; for the total, pain and function scores the extract was not inferior to ibuprofen at 4 weeks, while stiffness showed only a trend. Abdominal pain/discomfort occurred more often under ibuprofen [2].
Comparison with diclofenac: In an open-label study of 139 people (28 days), pain (VAS) and KOOS were similar under 3 × 500 mg curcumin (BCM-95) and under diclofenac (2 × 50 mg). Adverse effects were reported less often under curcumin (13% vs. 38%) [3]. Because of the open design, the strength of evidence is limited.
Placebo-controlled studies: In 40 people with mild to moderate knee osteoarthritis, WOMAC, VAS and LPFI scores fell more under 1,500 mg curcuminoids per day over 6 weeks than under placebo; for pain and function, not for stiffness [4]. In an 8-week study of 101 adults (2 × 500 mg Curcugen®), KOOS knee pain and pain ratings improved more than under placebo; pain-relieving medication was reduced in 37% of the curcumin group and 13% of the placebo group [5].
Pooled analyses: One meta-analysis (11 trials, 1,009 people) found better pain and function scores for curcuminoids than placebo, no significant differences versus NSAIDs, and fewer gastrointestinal adverse events. Study quality was low overall, and according to the authors the evidence is not adequate for clinical recommendations [6]. Another meta-analysis (11 trials, 1,258 people) saw similar pain effects at daily doses below and from 1,000 mg [7].
What this means in practice
The studies describe changes in symptom scores in knee osteoarthritis over 4 to 8 weeks, mostly at daily doses of 1,000 to 1,500 mg curcumin or curcuminoids. Preparations, doses and study designs differ considerably. More on the studies can be found in the osteoarthritis hub.
Limits of this statement
In 2017 EFSA could not establish a cause-and-effect relationship between curcumin and maintenance of joint function [8]; accordingly there is no authorised health claim for it. The results apply to knee osteoarthritis, not to other joints or forms of osteoarthritis. Many studies are small, short or open-label. This answer does not replace medical advice; chronic joint pain should be assessed by a doctor.
Common questions
We do not give a dose recommendation. Studies used: 1,500 mg Curcuma domestica extract per day for 4 weeks (367 patients; ibuprofen 1,200 mg/day as comparator) (Kuptniratsaikul et al., 2014) DOI, 1,500 mg curcuminoids per day in 3 divided doses for 6 weeks (40 patients, placebo) (Panahi et al., 2014) DOI, 500 mg curcumin extract twice daily for 8 weeks (Lopresti et al., 2021) DOI and 500 mg curcumin (BCM-95) three times daily for 28 days (Shep et al., 2019) DOI. For curcumin as a food additive (E 100), EFSA derived an acceptable daily intake (ADI) of 3 mg/kg body weight (EFSA, 2010) DOI.
The studies were short. They ran for 4 weeks (Curcuma domestica extract versus ibuprofen; WOMAC scores improved from baseline in both groups already at weeks 2 and 4) (Kuptniratsaikul et al., 2014) DOI, 28 days (curcumin versus diclofenac) (Shep et al., 2019) DOI, 6 weeks (curcuminoids versus placebo) (Panahi et al., 2014) DOI and 8 weeks (curcumin extract versus placebo) (Lopresti et al., 2021) DOI. This does not tell you when you might notice anything; for joint complaints, talk to your doctor.
No; the study showed comparability, not an advantage. In 367 patients with knee osteoarthritis, a Curcuma domestica extract (1,500 mg/day, 4 weeks) was non-inferior to ibuprofen (1,200 mg/day) at week 4 for WOMAC total, pain and function; for stiffness there was only a trend (P = 0.060) (Kuptniratsaikul et al., 2014) DOI. In an open-label study of 139 patients, pain and KOOS with curcumin (500 mg three times daily) were similar to diclofenac after 28 days (Shep et al., 2019) DOI.
In an 8-week study of 101 adults with knee osteoarthritis (500 mg curcumin extract twice daily or placebo), KOOS knee pain and pain ratings fell more with curcumin; pain-relieving medication was reduced in 37 % of the curcumin group versus 13 % of the placebo group (Lopresti et al., 2021) DOI. In a 6-week study of 40 patients, WOMAC scores fell more with curcuminoids (1,500 mg/day) than with placebo (Panahi et al., 2014) DOI. Turmeric may increase bleeding risk with warfarin or antiplatelet drugs PMID 30000906; discuss taking it alongside medication with your doctor.
In the study of Curcuma domestica extract versus ibuprofen, the number of patients with adverse events did not differ; abdominal pain or discomfort was more frequent with ibuprofen (Kuptniratsaikul et al., 2014) DOI. In the open-label diclofenac study, adverse effects were less frequent with curcumin (13 % versus 38 %) (Shep et al., 2019) DOI; in the placebo-controlled study of 40 patients, no considerable adverse effect was reported (Panahi et al., 2014) DOI. According to LactMed, turmeric is generally well tolerated, but nausea, diarrhoea and allergic reactions have been reported, and it may increase bleeding risk with warfarin or antiplatelet drugs PMID 30000906.
For knee osteoarthritis, the studies discussed here lasted 4 to 8 weeks (Kuptniratsaikul et al., 2014) DOI (Shep et al., 2019) DOI (Panahi et al., 2014) DOI (Lopresti et al., 2021) DOI; the authors of the 8-week study consider longer studies necessary (Lopresti et al., 2021) DOI. According to LactMed, turmeric is generally well tolerated, but gastrointestinal side effects and allergic reactions have been reported PMID 30000906. There is no source for a recommendation to review efficacy medically after four to six months; for long-term use, talk to your doctor.
Read more
Want to go deeper? Here is where to continue:
- Osteoarthritis guide: Detailed insights into the evidence on knee osteoarthritis.
- Safety check: Everything about the safety profile, possible side effects and important information on bleeding risks.
- Intake tips: Learn more about bioavailability, different formulations and absorption.
References
- [1] Csaki, C., Mobasheri, A. & Shakibaei, M. (2009). Synergistic chondroprotective effects of curcumin and resveratrol in human articular chondrocytes: inhibition of IL-1β-induced NF-κB-mediated inflammation and apoptosis. Arthritis Research & Therapy. DOI: 10.1186/ar2850
- [2] Kuptniratsaikul, V. et al. (2014). Efficacy and safety of Curcuma domestica extracts compared with ibuprofen in patients with knee osteoarthritis: a multicenter study. Clinical Interventions in Aging. DOI: 10.2147/CIA.S58535
- [3] Shep, D. et al. (2019). Safety and efficacy of curcumin versus diclofenac in knee osteoarthritis: a randomized open-label parallel-arm study. Trials. DOI: 10.1186/s13063-019-3327-2
- [4] Panahi, Y. et al. (2014). Curcuminoid Treatment for Knee Osteoarthritis: A Randomized Double-Blind Placebo-Controlled Trial. Phytotherapy Research. DOI: 10.1002/ptr.5174
- [5] Lopresti, A. L. et al. (2021). An Investigation into the Effects of a Curcumin Extract (Curcugen®) on Osteoarthritis Pain of the Knee: A Randomised, Double-Blind, Placebo-Controlled Study. Nutrients. DOI: 10.3390/nu14010041
- [6] Bannuru, R. R. et al. (2018). Efficacy of curcumin and Boswellia for knee osteoarthritis: Systematic review and meta-analysis. Seminars in Arthritis and Rheumatism. DOI: 10.1016/j.semarthrit.2018.03.001
- [7] Hsiao, A.-F. et al. (2021). The efficacy of high- and low-dose curcumin in knee osteoarthritis: A systematic review and meta-analysis. Complementary Therapies in Medicine. DOI: 10.1016/j.ctim.2021.102775
- [8] EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) (2017). Curcumin and normal functioning of joints: evaluation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006. EFSA Journal. DOI: 10.2903/j.efsa.2017.4774