|
| Study design | Phytoestrogens dose/preparation | Duration | Subjects | Purpose | Main results | References |
|
| Healthy individuals and postmenopausal women |
| Randomized control trial | High soya (100 mg total isoflavones/day) or a low soya (0.5 mg total isoflavones/day) diet | 10 weeks | (27)
Young healthy adults (15 men, 12 women) | Effects on memory, attention, and frontal lobe function | Improvements in short-term memory, long-term memory and mental flexibility | File et al., 2015 [159] |
| DB, CO, PC | 4 capsules/day containing soya isoflavones (116 mg isoflavone equivalents/day: 68 mg daidzein, 12 mg genistein, and 36 mg glycitin) or placebo | 6 weeks | (34)
Men aged 30-80 years | Effects on cognitive function | Improvements of spatial working memory but no effect on auditory and episodic memory and executive function and visual-spatial processing | Thorp et al., 2009 [160] |
18
R, DB, CO, PC | Isoflavone supplementation 60 mg/day or placebo | 6 months | (78)
Postmenopausal women (mean age 49.5 years) | Effects of soy isoflavones on mood and cognitive function in postmenopausal women | Improvements in mental flexibility, attention, mood, and lower depressive symptoms | Casini et al., 2006 [161] |
| R, DB, PC | 100 mg/day soy isoflavones (glycoside weight) or matching placebo tablets | 6 months | Older nondemented men and women (age 62-89 years) | Examination of safety, feasibility, and cognitive efficacy of soy isoflavone administration | Improvements of visual-spatial memory and construction of verbal fluency and speeded dexterity | Gleason et al., 2009 [162] |
| R, DB, PC | 20 g of soy protein containing 160 mg of total isoflavones | 12 weeks | (93)
Healthy postmenopausal women (mean age 56 years) | Effect of a high-dose isoflavones on cognition, quality of life, lipoproteins, and androgen status in postmenopausal women | Significant improvement in the quality of life versus placebo. No significant effects in cognition. The testosterone and HDL levels were significantly lower at the end of the study. | Basaria et al., 2009 [163] |
|
