Primary outcomes
The mean (SD) serum FBS level before intervention was 93.92 (9.12) in the curcumin group and 91.33 (9.40) in the placebo group so there was no statistically significant difference between the two groups (P = 0.314). After 12 weeks of intervention, the mean (SD) serum FBS level in the curcumin group was 90.38 (10.69) and in the placebo group it was 95.22 (11.22) which is significantly higher than the curcumin group (Mean Difference (MD): -6.24; 95% Confidence Interval (95% CI): -11.73 to -0.76; P = 0.027).The mean (SD) serum triglyceride level before intervention was 110.81 (47.11) in the curcumin group and 137.19 (43.20) in the placebo group which means a statistically significant difference between the two groups (P = 0.038). After 12 weeks of intervention, the mean (SD) serum triglyceride level in the curcumin group was 128.02 (6.13) and in the placebo group it was 136.27 (6.00) which means no statistically significant difference between the two groups (MD: -8.25; 95% CI: -25.85 to 9.35; P = 0.351).The mean (SD) serum cholesterol level before intervention was 158.46 (32.9) in the curcumin group and 162.59 (34.97) in the placebo group so there was no statistically significant difference between the two groups (P = 0.660). After 12 weeks of intervention, the mean (SD) serum cholesterol level in the curcumin group was 165.85 (37.69) and in the placebo group it was 174.19 (40.93) which means no statistically significant difference between the two groups (MD: -6.25; 95% CI: -26.13 to 13.57; P = 0.528).The mean (SD) serum LDL level before intervention was 88.77 (25.33) in the curcumin group and 91.11 (27.99) in the placebo group so there was no statistically significant difference between the two groups (P = 0.751). After 12 weeks of intervention, the mean (SD) serum LDL level in the curcumin group was 89.96 (30.92) and in the placebo group it was 105.70 (29.33) which means no statistically significant difference between the two groups (MD: -14.81; 95% CI: -30.52 to 0.91; P = 0.064).The mean (SD) serum HDL level before intervention was 50.12 (10.89) in the curcumin group and 105.70 (29.33) in the placebo group so there was no statistically significant difference between the two groups (P = 0.614). After 12 weeks of intervention, the mean (SD) serum HDL level in the curcumin group was 53.77 (13.15) and in the placebo group it was 51.56 (9.74) which means no statistically significant difference between the two groups (MD: 3.22; 95% CI: -3.04 to 9.48; P = 0.306).The mean (SD) serum fasting insulin level before intervention was 12.54 (7.56) in the curcumin group and 9.76 (7.25) in the placebo group so there was no statistically significant difference between the two groups (P = 0.135). After 12 weeks of intervention, the mean (SD) serum fasting insulin level in the curcumin group was 9.50 (7.02) and in the placebo group it was 10.11 (9.30) which means no statistically significant difference between the two groups (P = 0.929).The mean (SD) HOMA-IR before intervention was 2.88 (1.99) in the curcumin group and 2.16 (1.43) in the placebo group so there was no statistically significant difference between the two groups (P = 0.229). After 12 weeks of intervention, the mean (SD) serum HOMA-IR in the curcumin group was 2.11 (1.79) and in the placebo group it was 2.40 (2.11) which means no statistically significant difference between the two groups (P = 0.736).After the intervention, the mean (SD) serum testosterone level in the curcumin group was 0.64 (0.39) and in the placebo group it was 0.77 (0.36) which means no statistically significant difference between the two groups (0.133). After the intervention, the mean (SD) serum SHBG level in the curcumin group was 57.11 (38.57) and in the placebo group it was 60.67 (40.87) which means no statistically significant difference between the two groups (P = 0.682).The intra-group comparison results showed that there was statistical significant difference between before and after intervention in terms of fasting insulin level (P = 0.005) and HOMA-IR (P = 0.005) in the curcumin group. Also, the post-intervention FBS level increased significantly compared to pre-intervention level in the placebo group (P = 0.037) (Table 
Comparison of the metabolic indices levels by study groups* Standard Deviation; 