Turmeric (Curcuma longa) has been the subject of much interest over the last decade in terms of its applications in inflammatory illness, from Alzheimer’s, arthritis and autoimmune conditions to cancer and gastrointestinal problems.
As a culinary spice and ancient Ayurvedic plant, turmeric is a versatile medicine with a great safety profile and recently there has been an explosion of studies into the properties of curcumin, a group of chemicals in turmeric that are believed to be the active constituents. However, a word of caution; altering the natural balance of chemicals in plants by concentratingcertain substances at the expense of others or extracting certain compounds, can lead to an un-natural product that is more likely to produce undesired side effects. For this reason many herbalists believe generally that whole plant preparations are more beneficial.
Most research that has been carried out recently however pre-clinical, either lab-based or carried out on animals. In general, placebo-controlled randomized controlled trials are few and far between in herbal studies, being expensive and without the backing of any large funding organisations, however there have been several such trials on turmeric and extracts covering a range of onditions. Although herbal practice is mostly based on traditional use and trials usually serve to confirm those uses, it is always encouraging to see this typically highly valued evidence in the public domain.
Arthritis
One of the major uses of turmeric is as an anti-inflammatory in arthritic conditions and a 2012 randomized placebo-controlled trial (Madhu et al.,2012) was carried out with 120 patients suffereing from painful knee arthritis. The study was carried out over 6 weeks with administration of 1g of extract per day compared to placebo. A significant improvement compared to placebo was shown in clinical examination scores and use of rescue medication.
Another 4 week study on 80 osteoarthritis patients (Kertia et al., 2012) assessed the ability of 100mg daily of curcuminoids in reducing inflammation (via cycloxygenase-2 secretion by synovial fluid’s monocytes) compared to antiinflammatory medication diclofenac sodium. Both treatments reduced inflammatory markers by the same amount.
An Ayurvedic combination of Withania somnifera, Boswellia serrata, Zingiber officinale, and Curcuma longa was used in a randomized, double-blind, placebo-controlled, 32-week of 90 patients with primary osteoarthritis of the knees. The herbal combination was shown to significantly reduce symptoms of OA (Chopra et al., 2004).
Gingivitis
A 2012 trial (Mali et al.,2012; also Waghmare et al., 2011) compared the efficacy of 0.1% turmeric mouthwash as an anti-plaque agent and its effect on gingival inflammation compared with 0.2% chlorhexidine gluconate by evaluating the effect on plaque and gingival inflammation and on microbial load. 60 subjects, with mild to moderate gingivitis were studied over 3 weeks. Both mouthwashes significantly reduced gingival index, plaque Index and bacterial load by between 60-70%.
Cardiovascular function
Curcuminoids were shown to reduce incidence of heart attack after coronary artery bypass grafting (CABG). 121 patients were studied in a randomized placebo-controlled trial where the active treatment was 4g curcuminoids per day, beginning 3 days before the scheduled surgery and continued until 5 days after surgery. Incidence of myocardial infarction was significantly decreased from 30.0% in the placebo group to 13.1% in the curcuminoid group. Measures of inflammation, oxidation and vasodilation were also reduced in the curcuminoid group suggesting a mechanism for the action (Wongcharoen et al., 2012).
Skin conditions
Twenty patients with oral lichen planus were studied in a randomized, double-blind, placebo-controlled clinical trial. Curcuminoids at doses of 6000 mg/d were shown to significantly improve signs and symptoms (Chainani-Wu et al., 2012).
Kidney Function
A 3 month randomized, placebo-controlled study was carried out on 24 patients with lupus nephritis. 3 x 500mg turmeric extract was given each day and a significant decrease in proteinuria, systolic blood pressure and hematuria compared to no significant effect in placebo group (Khajehdehi et al., 2012).
A randomized, double-blind and placebo-controlled study was carried out over 2 months on 40 patients with diabetic nephropathy. End-stage renal disease (ESRD) due to diabetic nephropathy is a very common condition, associated with high levels of mortality and morbidity. One capsule containing 500 mg turmeric was taken with each meal and pathogenic markers TGF-β, IL-8 and urinary protein excretion decreased significantly (Khajehdehi et al., 2011).
Ulcerative Colitis
Eighty-nine patients with ulcerative colitis took part in a randomized, double-blind trial over 6 months. 2g of curumin was taken in addition to anti-inflammatory medication. Relapse rates were significantly improved in the curcumin group compared to placebo (Hanai et al., 2006).
References
Chainani-Wu N, Madden E, Lozada-Nur F, Silverman S Jr. 2012
High-dose curcuminoids are efficacious in the reduction in symptoms and signs
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Chopra A, Lavin P, Patwardhan B, Chitre D. 2004 A 32-week
randomized, placebo-controlled clinical evaluation of RA-11, an Ayurvedic drug,
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Hanai H, Iida T, Takeuchi K, Watanabe F, Maruyama Y, Andoh
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Kertia N, Asdie AH, Rochmah W, Marsetyawan. 2012 Ability of
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Khajehdehi P, Pakfetrat M, Javidnia K, Azad F, Malekmakan L,
Nasab MH, Dehghanzadeh G. 2011Oral supplementation of turmeric attenuates
proteinuria, transforming growth factor-β and interleukin-8 levels in patients
with overt type 2 diabetic nephropathy: a randomized, double-blind and
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Khajehdehi P, Zanjaninejad B, Aflaki E, Nazarinia M, Azad F,
Malekmakan L, Dehghanzadeh GR. 2012Oral supplementation of turmeric decreases
proteinuria, hematuria, and systolic blood pressure in patients suffering from
relapsing or refractory lupus nephritis: a randomized and placebo-controlled
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Waghmare PF, Chaudhari AU, Karhadkar VM, Jamkhande AS. 2011
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Wongcharoen W, Jai-Aue S, Phrommintikul A, Nawarawong W,
Woragidpoonpol S, Tepsuwan T, Sukonthasarn A, Apaijai N, Chattipakorn N. 2012
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