Turmeric and curcumin
Summary
NCCIH says there is not enough evidence to conclude turmeric or curcumin benefits any health purpose. Pooled trials found modest improvements in knee joint pain and post-exercise soreness, but no overall cognitive effect. Liver injury has been reported, including with high-bioavailability formulations; some implicated products also contained black pepper extract.
Key facts
- Turmeric powder and extracts, curcumin/curcuminoid extracts, and enhanced-bioavailability formulations (including curcumin with piperine)[1]
- Bioavailable formulations raise absorption; NCCIH warns they may harm the liver. Products vary in how much curcumin they contain[1]
- Knee pain and function ↑ (B); muscle soreness and damage markers after exercise ↓ (C); global cognition: no effect (C)[5][6][7]
- Conventional oral turmeric or curcumin is likely safe in recommended amounts for up to 2–3 months; liver injury, sometimes severe, has been reported[1][2][3]
- LiverTox: turmeric products have been implicated in several dozen cases of clinically apparent acute liver injury. A US network found 10 cases (1 death), typical onset 1–4 months, strongly linked to the HLA-B*35:01 gene variant[2][3]
- Sold in the US as dietary supplements, which FDA does not approve before sale[1]
- 3 graded human outcomes on this page
- October 9, 2026
How it works
ProposedThe health activities of turmeric are commonly attributed to curcuminoids, including curcumin. Anti-inflammatory and antioxidant effects are purported; curcumin improved memory in rodent models, but human cognitive findings are inconsistent (proposed).[1][2][7]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Bones & joints | Grade B | Improved | Meta-analysis · n = 1,009 · 2018 | 1 row |
| Focus | Grade C | No effect | Meta-analysis · n = 531 · 2025 | 1 row |
| Performance | Grade C | Worsened | Meta-analysis · n = 349 · 2024 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Knee joint pain and function | Improved | Grade B | Meta-analysis · n = 1,009 · 2018 Adults with knee osteoarthritis in 11 randomized controlled trials (curcumin and boswellia trials) Form: Curcuminoid formulations · Dose: Not stated in the abstract · Duration: Not stated in the abstract Curcuminoid formulations relieved knee pain and improved function more than placebo, with no difference in safety outcomes. | 29622343 (opens PubMed)Source [5] |
| Global cognition | No effect | Grade C | Meta-analysis · n = 531 · 2025 Participants in 10 human studies Form: Curcumin · Dose: Not stated in the abstract · Duration: Not stated in the abstract No significant effect on global cognition versus placebo (SMD 0.14). Subgroups showed better working memory and processing speed. Adverse events were more frequent with curcumin than with control. | 40579315 (opens PubMed)Source [7] |
| Post-exercise muscle soreness and damage markers | Worsened | Grade C | Meta-analysis · n = 349 · 2024 Participants in 14 studies of muscle-damaging exercise Form: Curcumin · Dose: Varied; low and higher doses analysed in subgroups · Duration: Varied Curcumin reduced muscle soreness (MD -0.61) and creatine kinase (MD -137.32), lowered IL-6 and improved range of motion versus control. | 39008500 (opens PubMed)Source [6] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Turmeric powder or conventional turmeric/curcumin extract | Varies[1] | NCCIH describes formulations that enhance the body's ability to absorb curcumin; our sources give no absorption figures for plain turmeric.[1] | Can cause nausea, vomiting, acid reflux, stomach upset, diarrhea or constipation; likely safe in recommended amounts for up to 2–3 months.[1] | Knee joint symptoms, cholesterol, exercise recovery |
| Enhanced-bioavailability curcumin (including curcumin with piperine from black pepper) | Varies[1] | Combining curcumin with piperine is one way to improve bioavailability; no head-to-head outcome comparison in our sources.[1] | Liver damage has been reported in some people taking bioavailable formulations; Italian cases involved high-bioavailability, high-dose products.[1][4] | Knee joint symptoms, exercise recovery |
Studied doses
Doses studied in human trials ranged from 250 mg of a turmeric extract to 1,000 mg or more of curcuminoids a day. Trial lengths are not given in the abstracts we opened; NCCIH considers conventional products likely safe for up to 2–3 months.[11][8][1]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
Medicines
- Prescription medicinesNIH fact sheetNCCIH advises talking with a health care provider before combining herbal products with any medicine because some herbs and medicines interact in harmful ways; in a review of 23 published turmeric liver-injury cases, most patients were also taking at least one other medication.[1][4]
Who should be careful
- Liver symptoms
- Turmeric products have been linked to dozens of cases of acute liver injury, including hospitalisations and a death. NCCIH advises stopping turmeric or curcumin immediately and contacting a provider if fatigue, nausea, poor appetite, dark urine or yellowing of the skin or eyes appear.[1][2][3]
- High-bioavailability or black pepper products
- Liver damage has been reported with bioavailable curcumin formulations; 3 of 7 products tested in US liver-injury cases also contained piperine.[1][3]
- Pregnancy and breastfeeding
- NCCIH says turmeric supplements may be unsafe in pregnancy, and little is known about amounts above food levels while breastfeeding.[1]
- Before you start
- Talk to your pharmacist or clinician before adding this supplement, especially if you take prescription medicines, are pregnant or breastfeeding, or have a chronic health condition.[1]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Articles about Turmeric and curcumin
Plain-English answers to common questions, built on the evidence above.
Frequently asked questions
Can turmeric harm the liver?
Rarely, yes. LiverTox notes several dozen cases of clinically apparent acute liver injury linked to turmeric products. In 10 US network cases, 5 people were hospitalised and 1 died; onset was typically 1–4 months after starting, and most carried the HLA-B*35:01 gene variant.[2][3]
Does turmeric help knee joints?
Meta-analyses found curcuminoids relieved knee pain and improved function more than placebo, but most trials were small and of low quality. NCCIH calls the evidence initially positive and says higher-quality studies are needed.[5][8][1]
Does curcumin help exercise recovery?
A meta-analysis of 14 studies (349 people) found less muscle soreness and lower creatine kinase after muscle-damaging exercise, with high heterogeneity between studies.[6]
Does curcumin lower cholesterol?
A meta-analysis of 64 trials found small improvements in total, LDL and HDL cholesterol and triglycerides, but rated the certainty low to very low.[9]
Why is curcumin combined with black pepper?
Piperine from black pepper improves curcumin's bioavailability. NCCIH warns that highly bioavailable curcumin may harm the liver, and US investigators suggested the rise in liver-injury cases may partly reflect combination with black pepper.[1][3]
Does curcumin improve memory?
Across 10 human studies (531 people), curcumin had no significant effect on global cognition, though some specific measures improved, and adverse events were more common than with placebo.[7]
What does the broadest curcumin review show?
A 2024 meta-analysis of 103 placebo-controlled trials (7,216 people) found significant effects for 23 of 42 outcomes, with high-credibility evidence only for fasting blood sugar, CRP, HDL cholesterol and weight.[10]
Sources
- [1]Turmeric: Usefulness and Safety (last updated April 2025). National Center for Complementary and Integrative Health, 2025. fact-sheet
- [2]Turmeric (LiverTox: Clinical and Research Information on Drug-Induced Liver Injury). National Institute of Diabetes and Digestive and Kidney Diseases (LiverTox), 2012. database
- [3]Liver Injury Associated with Turmeric-A Growing Problem: Ten Cases from the Drug-Induced Liver Injury Network [DILIN].. Am J Med, 2023. observational
- [4]Acute liver injury following turmeric use in Tuscany: An analysis of the Italian Phytovigilance database and systematic review of case reports.. Br J Clin Pharmacol, 2021. systematic-review
- [5]Efficacy of curcumin and Boswellia for knee osteoarthritis: Systematic review and meta-analysis.. Semin Arthritis Rheum, 2018. meta-analysis
- [6]Meta-analysis of the effect of curcumin supplementation on skeletal muscle damage status.. PLoS One, 2024. meta-analysis
- [7]Targeting cognitive aging with curcumin supplementation: A systematic review and meta-analysis.. J Prev Alzheimers Dis, 2025. meta-analysis
- [8]The efficacy of high- and low-dose curcumin in knee osteoarthritis: A systematic review and meta-analysis.. Complement Ther Med, 2021. meta-analysis
- [9]Effects of curcumin/turmeric supplementation on lipid profile: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials.. Complement Ther Med, 2023. meta-analysis
- [10]Curcumin on Human Health: A Comprehensive Systematic Review and Meta-Analysis of 103 Randomized Controlled Trials.. Phytother Res, 2024. meta-analysis
- [11]Safety and Efficacy of Turmeric (Curcuma longa) Extract and Curcumin Supplements in Musculoskeletal Health: A Systematic Review and Meta-Analysis.. Altern Ther Health Med, 2023. meta-analysis
What changed
- First draft. Every evidence-row PMID checked with NCBI E-utilities (esummary + efetch abstract) and re-read in an independent adversarial pass.