Ann Intern Med. 2005 Jul 5;143(1):1-9.

大豆蛋白质对血压的影响：一项随机对照试验

研究背景：流行病学显示植物蛋白摄取与血压水平呈负相关。
目的：研究大豆蛋白质对高血压前期或高血压1级患者血压的影响。
设计：随机双盲对照试验
受试者：302名未经治疗的中国受试者，年龄在35-64岁之间，基线收缩压在130-159mmHg之间，或舒张压在80-99mmHg，或两种情况兼有。
干预：受试者随机分为两组，试验组每天食用40克大豆蛋白质，对照组每天食用40克碳水化合物，一共12周，有91.4％的人完成了试验。
测量：试验开始时，6周和12周分别测量血压
结果：基线平均收缩压和舒张压分别是135mmHg(标准差为10.9)和84.7mmHg（标准差为6.9）。干预12周后与对照组相比，大豆治疗组受试者的收缩压和舒张压分别下降4.31mmHg（95% 可信区间，-2.11至-6.51mmHg；P < 0.001）和2.76mmHg（可信区间，-1.35至-4.16mmHg；P < 0.001）。其中高血压患者下降更明显，为7.88mmHg （可信区间，-4.66至-11.1 mmHg）和5.27mmHg （可信区间，-3.05至-7.49mmHg），而血压正常者下降不明显，为2.34mmHg (可信区间，0.48至-5.17mmHg)和1.28mmHg（可信区间，0.52至-3.07mmHg）。
局限性：本试验并未证实血压下降到底是由大豆中的蛋白质还是异黄酮所致的。
结论:摄入大豆蛋白质可降血压。此结果显示增加大豆蛋白质摄取可预防和治疗高血压。

Effect of soybean protein on blood pressure: a randomized, controlled trial.

He J, Gu D, Wu X, Chen J, Duan X, Chen J, Whelton PK.

BACKGROUND: Epidemiologic studies suggest that vegetable protein intake is inversely related to blood pressure. OBJECTIVE: To examine the effect of soybean protein supplementation on blood pressure in persons with prehypertension or stage 1 hypertension. DESIGN: Randomized, double-blind, controlled trial. SETTING: Three communities in the People's Republic of China. PATIENTS: 302 participants 35 to 64 years of age with an initial untreated systolic blood pressure of 130 to 159 mm Hg, diastolic blood pressure of 80 to 99 mm Hg, or both. INTERVENTION: Study participants were randomly assigned to receive 40 g of isolated soybean protein supplements per day or complex carbohydrate control for 12 weeks; 91.4% completed the intervention. MEASUREMENTS: Blood pressure measurements were obtained by using random-zero sphygmomanometers at baseline and at 6 and 12 weeks. RESULTS: At baseline, the mean systolic and diastolic blood pressures were 135.0 mm Hg (SD 10.9) and 84.7 mm Hg (SD 6.9), respectively. Compared with the control group, the net changes in systolic blood pressure and diastolic blood pressure were -4.31 mm Hg (95% CI, -2.11 to -6.51 mm Hg; P < 0.001) and -2.76 mm Hg (CI, -1.35 to -4.16 mm Hg; P < 0.001), respectively, after the 12-week intervention. The net changes in systolic and diastolic blood pressure reductions were -7.88 mm Hg (CI, -4.66 to -11.1 mm Hg) and -5.27 mm Hg (CI, -3.05 to -7.49 mm Hg), respectively, in persons with hypertension and -2.34 mm Hg (CI, 0.48 to -5.17 mm Hg) and -1.28 mm Hg (CI, 0.52 to -3.07 mm Hg), respectively, in those without hypertension. LIMITATIONS: This trial did not examine whether the blood pressure reduction was due to protein or isoflavones in soybean. CONCLUSIONS: Soybean protein supplementation resulted in a reduction in systolic and diastolic blood pressure. These findings suggest that increased intake of soybean protein may play an important role in preventing and treating hypertension.