TABLE 1.
Clinical trials testing soy foods
| Publication (reference) | Intervention | n | Duration | Age, y | Outcomes | Results | Comments |
| Wilcox et al., 1990 (18) | Soy flour vs. red clover sprouts vs. linseed | 25 | 2 wk | 51–70 | Vaginal MV | MV increased | |
| Baird et al., 1995 (19) | Daily dish made from whole soybeans vs. texturized vegetable soy protein vs. usual diet1 | 19 | 4 wk | 45–65 | VMI2 | Negative findings | |
| Murkies et al., 1995 (20) | Soy flour vs. wheat flour | 58 | 12 wk | 3 | VMS and VMI4 | Negative findings | 19% dropout |
| Brzezinski et al., 1997 (21) | Soy foods vs. usual diet | 145 | 12 wk | 43–65 | VMS and UGS5 | Significant reduction in symptoms | |
| Dalais et al., 1998 (22) | Bread made with 45 g soy grits6 vs. wheat bread vs. linseed bread | 52 | 12 wk | 45–65 | VMS and VMI | Increase in VMI | 20% dropout |
| Chiechi et al., 2003 (23) | Encouraged 1 soy food serving daily vs.ET7 vs. placebo | 187 | 6 mo | 39–60 | MV and KI | Increase in MV and KI | 42% dropout in soy food group |
| Newton et al., 2005 (24, 25) | Multibotanical + soy dietary counseling vs. multibotanical vs. black cohosh vs. ET vs. placebo | 351 | 12 mo | 45–65 | VMS | Increased VMS in the multibotanical + soy group | |
| Lewis et al., 2006 (26) | Soy flour muffins vs. wheat vs. flaxseed | 99 | 16 wk | 45–60 | VMS | Negative findings | |
| Manonai et al., 2006 (27) | Soy-rich foods8 vs. animal protein | 42 | 12 wk | 45–70 | VHI9 | Negative findings | 15% dropout |
| Welty et al., 2007 (28) | Soy nuts | 60 | 8 wk | 10 | VMS and Menopause-Specific QoL11 | 41–45% decrease in VMS | 27% dropout |
1
165 mg isoflavones.
2
VMI, vaginal MI.
3
Mean age in group with ≤4.5 hot flashes/d 51.9 ± 5.5 y and 54.6 ± 5.4 y in group > 4.5 hot flashes/d.
4
VMS, vasomotor symptoms.
5
UGS, urogenital symptoms.
6
52 mg/d isoflavones.
7
ET, estrogen therapy.
8
50 mg/d isoflavones.
9
VHI, vaginal health index.
10
Mean age 53.8 ± 1.0 y in soy group and 56.0 ± 0.9 y in wheat group.
11
QoL, Quality of Life questionnaire.