Effect of soy nuts on blood pressure and lipid levels in hypertensive, prehypertensive, and normotensive postmenopausal women.

BACKGROUND: Epidemiologic studies suggest a low incidence of cardiovascular disease in populations that consume dietary soy. For people aged 40 to 70 years, each increment of 20 mm Hg in systolic blood pressure (BP) or 10 mm Hg in diastolic BP doubles the risk of cardiovascular disease for BPs of 115/75 to 185/115 mm Hg. METHODS: To determine the effect of soy nuts on systolic and diastolic BP and lipid levels, 60 healthy postmenopausal women were randomized in a crossover design to a Therapeutic Lifestyle Changes (TLC) diet alone and a TLC diet of similar energy, fat, and protein content in which soy nuts (containing 25 g of soy protein and 101 mg of aglycone isoflavones) replaced 25 g of non-soy protein. Each diet was followed for 8 weeks. RESULTS: Compared with the TLC diet alone, the TLC diet plus soy nuts lowered systolic and diastolic BP 9.9% and 6.8%, respectively, in hypertensive women (systolic BP> or =140 mm Hg) and 5.2% and 2.9%, respectively, in normotensive women (systolic BP<120 mm Hg). Further subdivision of normotensive women revealed that systolic and diastolic BPs were lowered 5.5% and 2.7%, respectively, in prehypertensive women (systolic BP of 120-139 mm Hg) and 4.5% and 3.0%, respectively, in normotensive women. Soy nut supplementation lowered low-density lipoprotein cholesterol and apolipoprotein B levels 11% and 8% (P = .04 for both), respectively, in hypertensive women but had no effect in normotensive women. CONCLUSIONS: Substituting soy nuts for nonsoy protein in a TLC diet improves BP and low-density lipoprotein cholesterol levels in hypertensive women and BP in normotensive postmenopausal women. These findings may explain a cardioprotective effect of soy.

The association between soy nut consumption and decreased menopausal symptoms.

BACKGROUND: Epidemiological studies suggest a low incidence of hot flashes in populations that consume dietary soy. The present study examined the effect of soy nuts on hot flashes and menopausal symptoms. METHODS: Sixty healthy postmenopausal women were randomized in a crossover design to a therapeutic lifestyle changes (TLC) diet alone and a TLC diet of similar energy, fat, and protein content in which one-half cup soy nuts divided into three or four portions spaced throughout the day (containing 25 g soy protein and 101 mg aglycone isoflavones) replaced 25 g of nonsoy protein. During each 8-week diet period, subjects recorded the number of hot flashes and amount of exercise daily. At the end of each 8-week diet period, subjects filled out the menopausal symptom quality of life questionnaire. RESULTS: Compared to the TLC diet alone, the TLC diet plus soy nuts was associated with a 45% decrease in hot flashes (7.5 +/- 3.6 vs. 4.1 +/- 2.6 hot flashes day, respectively, p < 0.001) in women with >4.5 hot flashes/day at baseline and 41% in those with