Table 1 Characteristics of twenty-four randomized controlled trials included in the meta-analysis
First author, year | Country | Duration of intervention (months) | Study design | Sample size (isoflavone/control) | Mean age (year) | BMI (kg/m2) | Women (%) | Population | Intervention | ||
|---|---|---|---|---|---|---|---|---|---|---|---|
Soy isoflavone group | Control group | ||||||||||
Simon et al. 2000 [42] | Australia | 2 | Crossover | 20/20 | 59.0 | 26.8 | 100.0 | Healthy postmenopausal women | 80 mg soy isoflavone (PhytoLife 1) | Placebo (NR) | |
Han et al. 2002 [43] | Brazil | 4 | Parallel | 40/40 | 48.5 | 24.9 | 100.0 | Postmenopausal women | 100 mg soy isoflavone (50.3 mg soy protein and 33.3 mg isoflavone per capsule) | Placebo (50.3 mg soy protein and 33.3 mg glucose per capsule) | |
Squadrito et al. 2002 [44] | Italy | 6 | Parallel | 30/30 | 56.0 | NR | 100.0 | Healthy Postmenopausal women | 54 mg soy isoflavone (genistein) | Placebo (NR) | |
Uesugi et al. 2004 [45] | Japan | 1 | Crossover | 58/58 | 58.0 | 23.0 | 100.0 | Climacteric women | 40 mg soy isoflavone (3.4 mg daidzein, 0.9 mg genistein, and 2.7 mg glycitein per gram of tablet) | Placebo (same matrix without isoflavone) | |
Colacurci et al. 2005 [24] | Italy | 6 | Parallel | 29/28 | 55.2 | 25.9 | 100.0 | Healthy postmenopausal women | 120 mg soy isoflavone (60 mg genistein and 60 mg daidzein) | Placebo (NR) | |
Yildiz et al. 2005 [25] | Turkey | 6 | Parallel | 20/20 | 50.0 | 27.2 | 100.0 | Healthy postmenopausal women | 40 mg soy isoflavone (genistein) | Placebo (NR) | |
Hallund et al. 2006 [46] | Denmark | 2 | Crossover | 30/28 | 57.0 | 24.0 | 100.0 | Healthy postmenopausal women | Cereal bars with 50 mg soy isoflavone (genistein:daidzein ratio of 2:1) | Placebo (cereal bars) | |
Gonzalez et al. 2007 [47] | United Kingdom | 3 | Crossover | 26/26 | NR | 31.0 | 100.0 | Postmenopausal women with type 2 diabetes | 132 mg soy isoflavone (53% genistein, 37% daidzein, and 10% glycitein) | Placebo (microcrystalline cellulose) | |
Katz et al. 2007 [48] | United States | 1.5 | Crossover | 22/22 | 58.5 | 27.6 | 100.0 | Healthy postmenopausal women | 55 mg soy isoflavone (daidzein and genistein) | Placebo (NR) | |
Aubertin-Leheudr et al. 2008 [49] | Canada | 6 | Parallel | 25/25 | 57.4 | 32.0 | 100.0 | Postmenopausal obese women | 70 mg soy isoflavone (44 mg daidzein, 16 mg glycitein, and 10 mg genistein) | Placebo (NR) | |
Khaodhiar et al. 2008 [50] | United States | 3 | Parallel | 97/45 | 53.1 | 28.6 | 100.0 | Healthy menopausal women | 40 or 60 mg soy isoflavone (70% daidzein, 10% genistein, and 20% glycitein) | Placebo (NR) | |
Gleason et al. 2009 [51] | United States | 6 | Parallel | 15/15 | 73.7 | NR | 50.0 | Healthy men and postmenopausal women | 100 mg soy isoflavone (85% daidzein and genistein) | Placebo (maltodextrin and caramel food colour) | |
Llaneza et al. 2010 [52] | Spain | 24 | Parallel | 58/58 | 56.4 | 30.0 | 100.0 | Postmenopausal women with insulin resistance | Mediterranean diet with 40 mg soy isoflavone (NR) | Placebo (mediterranean diet) | |
Wong et al. 2012 [53] | United States | 1.5 | Parallel | 12/12 | 55.7 | 25.4 | 100.0 | Postmenopausal women | 80 mg soy isoflavone (22.0 mg daidzein, 13.5 mg glycitein, and 5.0 mg genistein per tablet) | Placebo (1.0 mg aglycone equivalent per tablet) | |
Chilibeck et al. 2013 [54] | Canada | 24 | Parallel | 90/88 | 56.6 | 27.1 | 100.0 | Postmenopausal women | 165 mg soy isoflavone (105 mg aglycone equivalent) | Placebo (dicalcium phosphate, magnesium stearate, and sorbitol) | |
Irace et al. 2013 [26] | Italy | 6 | Parallel | 10/10 | 58.8 | 31.8 | 100.0 | Postmenopausal women with metabolic syndrome | 54 mg soy isoflavone (genistein) | Placebo (NR) | |
Kim et al. 2013 [55] | Korea | 3 | Parallel | 42/43 | 53.6 | 23.2 | 100.0 | Postmenopausal women with type 2 diabetes | 70 mg soy isoflavone (38.0 mg glycitein, 20 mg daidzein, and 12.4 mg genistein) | Placebo (NR) | |
Liu et al. 2013 [21] | China | 6.25 | Parallel | 60/60 | NR | NR | 100.0 | Postmenopausal women | 15 g milk protein and 100 mg isoflavone (35 mg daidzein, 59 mg genistein, and 4 mg glycitein) | Placebo (15 g milk protein) | |
Squadrito et al. 2013 [22] | Italy | 12 | Parallel | 60/60 | 55.5 | 31.8 | 100.0 | Postmenopausal women with metabolic syndrome | 54 mg soy isoflavone (genistein) | Placebo (NR) | |
Cheng et al. 2015 [56] | China | 12 | Parallel | 41/41 | 56.6 | 23.0 | 100.0 | Postmenopausal women | 300 mg isoflavone aglycone (NR) | Placebo (NR) | |
De Gregorio et al. 2017 [57] | Italy | 12 | Parallel | 11/11 | NR | 30.3 | 100.0 | Postmenopausal women with metabolic syndrome | 54 mg soy isoflavone (genistein) | Placebo (NR) | |
Sathyapalan et al. 2017 [58] | United Kingdom | 3 | Parallel | 100/100 | 52.0 | 31.7 | 0.0 | Men with type 2 diabetes | 15 g soy protein with 66 mg isoflavone (54% genistein, 35% daidzein, and 11% glycitein) | Placebo (15 g soy protein) | |
Amanat et al. 2018 [59] | Iran | 2 | Parallel | 41/41 | 43.6 | 28.5 | 24.4 | Patients with non-alcoholic fatty liver disease | 250 mg soy isoflavone (genistein) | Placebo (cornstarch) | |
Sathyapalan et al. 2018 [23] | United Kingdom | 6 | Parallel | 60/60 | 52.0 | 25.5 | 100.0 | Early menopause women | 15 g soy protein with 66 mg isoflavone (54% genistein, 35% daidzein, and 11% glycitein) | Placebo (15 g soy protein) | |