Simon J A, Obarzanek E, Daniels S R, Frederick M M
Department of Medicine, Veterans Affairs Medical Center, San Francisco, CA 94121.
Am J Epidemiol. 1994 Jan 15;139(2):130-40. doi: 10.1093/oxfordjournals.aje.a116975.
The authors examined the relative importance of dietary sodium, potassium, calcium, and magnesium intakes as correlates of blood pressure in a cross-sectional analysis of 987 black and 1,043 white 9- and 10-year-old girls from Richmond, California, Cincinnati, Ohio, and Washington, DC, who were enrolled in the National Heart, Lung, and Blood Institute Growth and Health Study between January 1987 and May 1988. Dietary intake was measured using a 3-day food record. Dietary cation intake was not associated with blood pressure in black girls. An inverse association between magnesium intake and diastolic (fifth Korotkoff phase) blood pressure was found in white girls (p < 0.01). After controlling for factors often associated with blood pressure, such as pulse rate, body mass index, and household income, the authors found that dietary magnesium intake (range, 53-511 mg/day) continued to be associated with diastolic (fifth Korotkoff phase) blood pressure in white girls, such that each 100-mg/day increase in intake was associated with a 3.22-mmHg decrease in diastolic pressure (95% confidence interval -5.70 to -0.75). However, after adjustment for dietary fiber intake, the authors were no longer able to discern an association between dietary magnesium intake and blood pressure. They conclude that the body mass index and pulse rate are the strongest correlates of blood pressure in 9- and 10-year-old black girls and white girls and that studies examining the relation between dietary magnesium and blood pressure should control for the effects of dietary fiber intake.
作者们对987名黑人及1043名白人9至10岁女孩的饮食钠、钾、钙和镁摄入量作为血压相关因素的相对重要性进行了研究。这些女孩来自加利福尼亚州里士满、俄亥俄州辛辛那提和华盛顿特区，于1987年1月至1988年5月参加了美国国立心肺血液研究所的生长与健康研究。饮食摄入量通过3天食物记录来测量。黑人女孩的饮食阳离子摄入量与血压无关。在白人女孩中发现镁摄入量与舒张压（柯氏第五音）血压呈负相关（p<0.01）。在控制了通常与血压相关的因素，如脉搏率、体重指数和家庭收入后，作者发现白人女孩的饮食镁摄入量（范围为53 - 511毫克/天）仍与舒张压（柯氏第五音）血压相关，摄入量每增加100毫克/天，舒张压下降3.22毫米汞柱（95%置信区间为-5.70至-0.75）。然而，在调整膳食纤维摄入量后，作者不再能够辨别饮食镁摄入量与血压之间的关联。他们得出结论，体重指数和脉搏率是9至10岁黑人女孩和白人女孩血压的最强相关因素，并且研究饮食镁与血压之间关系的研究应控制膳食纤维摄入量的影响。
