Table 3 The characteristics of the included studies
Study | Sample size | Intervention | Relevant outcomes | Mean age (years) | Mean BMI (baseline) | Duration | ||||
|---|---|---|---|---|---|---|---|---|---|---|
Trial group | Control group | Trial group | Control group | Trial group | Control group | Trial group | Control group | |||
Mohammadi 2012 [25] | 30 | 31 | Omega-3 fatty acids 4000 mg | Paraffin oil (placebo) 2000 mg | BMI, TG, TC, LDL-C, HDL-C, Adiponectin, fasting insulin, fasting glucose, the change of HOMA | 27.33 ± 4.27 | 27.73 ± 4.53 | 28.67 ± 3.21 | 28.77 ± 2.92 | 8 weeks |
Karakas 2016 [17] | 34 | 17 | Omega-3 fatty acids (including fish oils and flaxseed oils) | Soybean oil (placebo) | BMI, TG, TC, LDL-C, HDL-C, fasting insulin, fasting glucose, the change of HOMA | Fish oils: 31.7 ± 7.8; Flaxseed oils: 29.4 ± 6.6 | 28.9 ± 4.1 | Fish oils: 36.3 ± 7.8; Flaxseed oils: 35.0 ± 10.3 | 33.2 ± 7.4 | 6 weeks |
Nadjarzadeh 2015 [18] | 39 | 39 | Omega-3 fatty acids 900 mg | Paraffin oil (placebo) 3000 mg | BMI, Adiponectin, FSH, LH | 26.9 ± 5.9 | 26.9 ± 5.0 | 31.46 ± 5.74 | 31.88 ± 3.86 | 12 weeks |
Nadjarzadeh 2013 [26] | 39 | 39 | Omega-3 fatty acids 900 mg | Paraffin oil (placebo) 3000 mg | Total testosterone, SHGB | 26.9 ± 5.9 | 26.9 ± 5.0 | 31.46 ± 5.74 | 31.88 ± 3.86 | 12 weeks |
Rahmani 2017 [19] | 34 | 34 | Omega-3 fatty acids 1000 mg + Vitamin E 400 IU + Metformin | Placebos + Metformin | BMI, TG, TC, LDL-C, HDL-C, FSH, LH | 24.9 ± 5.5 | 26.6 ± 5.6 | 28.4 ± 4.4 | 29.0 ± 6.5 | 12 weeks |
Ebrahimi 2017 [20] | 34 | 34 | Omega-3 fatty acids 1000 mg + vitamin E 400 IU | Placebos | BMI, SHGB, fasting insulin, fasting glucose, the change of HOMA, total testosterone | 23.8 ± 4.6 | 25.2 ± 5.2 | 28.0 ± 4.3 | 28.5 ± 6.6 | 12 weeks |
Khani 2017 [8] | 43 | 44 | Omega-3 fatty acids 2000 mg | Olive oil (placebo) 2000 mg | BMI, TG, TC, LDL-C, HDL-C, fasting glucose | 31.04 ± 5.04 | 29.23 ± 6.73 | 31.8 ± 3.61 | 31.79 ± 3.6 | 24 weeks |
Mirmasoumi 2017 [27] | 30 | 30 | Omega-3 fatty acids 2000 mg + Metformin 500 mg | Paraffin oil (placebo) 1000 mg + Metformin 500 mg | BMI, TG, TC, LDL-C, HDL-C, fasting insulin, fasting glucose, the change of HOMA, total testosterone, SHBG, adverse events | 28.4 ± 6.4 | 27.0 ± 3.2 | 26.9 ± 5.1 | 26.7 ± 5.3 | 12 weeks |
Jamilian 2018 [28] | 20 | 20 | Omega-3 fatty acids 1000 mg + Vitamin E 400 IU | Paraffin oil (placebo) | BMI, the change of HOMA | 22.3 ± 4.7 | 24.4 ± 4.7 | 28.8 ± 5.1 | 26.5 ± 5.9 | 12 weeks |