TABLE 3.
Descriptive statistics for blood lipids and hormones in the 3 treatment groups at baseline and after 1 and 2 y of soy isoflavone supplementation1
| Soy isoflavone–treated groups |
||||
| Variables (normal range) and sequence | Placebo | 80 mg/d | 120 mg/d | 2 |
| Blood lipids | ||||
| Cholesterol (0–200 mg/dL) | ||||
| Baseline | 213.2 ± 32.5 | 218.7 ± 33.4 | 215.4 ± 34.6 | 0.399 |
| 1 y | 211.1 ± 33.8 | 215.9 ± 36.1 | 212.9 ± 37.4 | 0.924 |
| 2 y | 209.0 ± 32.6 | 216.8 ± 35.6 | 213.5 ± 39.5 | 0.787 |
| Triglycerides (35–160 mg/dL) | ||||
| Baseline | 95.2 ± 41.2 | 100.0 ± 57.7 | 97.6 ± 49.2 | 0.729 |
| 1 y | 93.7 ± 42.1 | 99.8 ± 47.5 | 98.5 ± 57.0 | 0.762 |
| 2 y | 102.1 ± 54.2 | 104.3 ± 54.1 | 101.5 ± 68.7 | 0.802 |
| HDL cholesterol (>35 mg/dL) | ||||
| Baseline | 68.1 ± 15.6 | 67.3 ± 16.3 | 68.1 ± 18.1 | 0.905 |
| 1 y | 66.6 ± 14.2 | 65.1 ± 15.4 | 67.0 ± 16.7 | 0.396 |
| 2 y | 64.7 ± 14.6 | 63.1 ± 15.1 | 65.3 ± 16.6 | 0.557 |
| LDL cholesterol (<130 mg/dL) | ||||
| Baseline | 126.1 ± 30.0 | 131.4 ± 30.5 | 127.9 ± 30.9 | 0.359 |
| 1 y | 125.2 ± 30.2 | 130.5 ± 33.5 | 127.0 ± 32.5 | 0.811 |
| 2 y | 123.9 ± 29.3 | 133.6 ± 31.9 | 127.6 ± 34.8 | 0.298 |
| Endocrine profile | ||||
| TSH (0.35–5.5 μIU/mL) | ||||
| Baseline | 2.8 ± 7.4 | 2.2 ± 1.5 | 2.4 ± 2.9 | 0.612 |
| 1 y | 2.6 ± 2.4 | 2.5 ± 1.6 | 2.6 ± 3.2 | 0.850 |
| 2 y | 2.4 ± 1.4 | 2.4 ± 1.3 | 2.2 ± 1.2 | 0.264 |
| FT4 (0.80–1.80 ng/dL) | ||||
| Baseline | 1.1 ± 0.2 | 1.2 ± 0.2 | 1.2 ± 0.2 | 0.810 |
| 1 y | 1.1 ± 0.2 | 1.2 ± 0.2 | 1.2 ± 0.2 | 0.739 |
| 2 y | 1.2 ± 0.2 | 1.1 ± 0.1 | 1.1 ± 0.2 | 0.052 |
| Hormone profile (postmenopausal) | ||||
| LH (7.7–58.5 mIU/mL) | ||||
| Baseline | 36.4 ± 11.5 | 37.0 ± 13.9 | 41.8 ± 14.0 | 0.112 |
| 1 y | 36.8 ± 12.4 | 36.7 ± 16.9 | 37.2 ± 13.3 | 0.382 |
| 2 y | 34.5 ± 13.2 | 34.9 ± 19.0 | 41.2 ± 13.7 | 0.490 |
| FSH (23–117 mIU/mL) | ||||
| Baseline | 74.2 ± 24.0 | 76.8 ± 26.7 | 82.2 ± 30.8 | 0.052 |
| 1 y | 72.6 ± 24.8 | 75.0 ± 29.6 | 75.8 ± 30.7 | 0.284 |
| 2 y | 72.0 ± 23.5 | 78.2 ± 30.0 | 80.3 ± 32.4 | 0.365 |
| Estradiol (<10–31 ng/dL) | ||||
| Baseline | 25.1 ± 23.9 | 24.8 ± 22.3 | 27.2 ± 27.5 | 0.685 |
| 1 y | 26.8 ± 29.5 | 25.5 ± 23.8 | 27.6 ± 27.7 | 0.848 |
| 2 y | 24.2 ± 21.7 | 25.0 ± 21.7 | 27.7 ± 26.5 | 0.126 |
1
All values are means ± SDs. TSH, thyrotropin; FT4, free thyroxine; LH, luteinizing hormone; FSH, follicle-stimulating hormone.
2
P values for baseline and years 1 and 2 were derived from a multivariate model ANOVA with adjustment for study site, soy intake, and pretreatment values. The interaction terms were not significant. Number of study participants at baseline (placebo: 134; 80 mg/d: 135; 120 mg/d: 134), after 1 y of treatment (placebo: 128; 80 mg/d: 122; 120 mg/d: 123), and after 2 y of treatment (placebo: 126; 80 mg/d: 119; 120 mg/d: 117).