Table 1.

Characteristics of studies included in the meta-analysis

Study	Region	Type	Duration	Inclusion criteria		Intervention	N	Age	Male
Metabolic syndrome
Rahmani et al. 2016 [23]	Iran	RCT double-blind	8 weeks	Patients with symptoms of MetS (NCEP-ATP III) and diagnosis of NAFLD	Case	Amorphous dispersion Curcumin (amorphous dispersion preparation, equivalent to 70 mg/d curcuminoids)	37	46.37 ± 11.57	19
					Control	Placebo	40	48.95 ± 9.78	19
Amin et al. 2015 [26]	Pakistan	RCT double-blind	8 weeks	Patients with ≥ 3 features of MetS, prediabetes, dyslipidemia and prehypertension	Case	Turmeric powder 2.4 g/d	63	42.40 ± 13.70	NA
					Control	Placebo	63	41.57 ± 12.80	NA
Yang et al. 2014 [27]	Taiwan	RCT double-blind	12 weeks	Patients with diagnosis of MetS (NCEP-ATP III)	Case	Turmeric extract (equivalent to 1890 mg/d curcuminods)	30	59.03 ± 10.10	12
					Control	Placebo	29	59.61 ± 14.09	17
Type 2 diabetes mellitus
Rahimi et al. 2016 [24]	Iran	RCT double-blind	3 months	Type 2 Diabetic patients	Case	Curcumin (nano-micelle 80 mg/day)	35	56.34 ± 11.17	17
					Control	placebo	35	60.95 ± 10.77	14
Selvi et al. 2015 [25]	India	RCT	4 weeks	Type 2 diabetic patients	Case	Turmeric powder 2 g/day +Metformin	30	47.00 ± 7.17	30
					Control	Metformin (1 g/day)	30	46.80 ± 6.10	30
Chuengsamarn et al. 2014 [28]	Thailand	RCT double-blind	6 months	Type 2 diabetic patients	Case	Turmeric extract (equivalent to 1500 mg/d curcuminods)	107	59.16 ± 11.04	50
					Control	Placebo	106	59.58 ± 10.71	47
Usharani et al. 2008 [15]	India	RCT	8 weeks	Type 2 diabetic patients	Case	Turmeric extract (equivalent to 600 mg/day curcuminoids)	23	55.52 ± 10.76	12
					Control	Placebo	21	49.75 ± 8.18	11

MetS metabolic syndrome, NAFLD nonalcoholic fatty liver disease, NCEP-ATP III National Cholesterol Education Program Adult Treatment Panel III, a diagnostic guideline of MetS, RCT randomized controlled trial, NA not available

Values are expressed as mean ± SD