A prospective cohort study of adolescent girls in the US concluded that consumption of 3500 mg/d of sodium or more had no adverse effect on blood pressure. The beneficial effects of dietary potassium on both systolic and diastolic blood pressures suggest that consuming more potassium-rich foods during childhood may help suppress the adolescent increase in blood pressure. Participants included 2185 black and white girls initially aged 9 to 10 years from March 1987 and follow-up continued for 10 years. Dietary assessment was conducted using 3-day diet records on two weekdays and one weekend day during eight of the 10 study years. There was no evidence that higher sodium intakes (3000 to <4000 mg/d and ≥4000 mg/d vs <2500 mg/d) had an adverse effect on adolescent blood pressure and longitudinal mixed models showed that those consuming 3500 mg/d or more had generally lower diastolic blood pressures compared with individuals consuming less than 2500 mg/d. However, higher potassium intakes were inversely associated with blood pressure change throughout adolescence and at the end of follow-up. While the potassium to sodium ratio was also inversely associated with systolic blood pressure, these effects were generally weaker compared with effects for potassium alone. Beans, dark leafy greens, dried fruit, avocados, yogurt, bananas and fish are good dietary sources of potassium. Source: http://archpedi.jamanetwork.com/美国一项对青春期少女的前瞻性群组研究得出结论，钠摄入3500毫克/天或以上对血压没有不良影响。饮食钾对收缩压和舒张压的有益效果表明，儿童时期食用更多富含钾的食物可能有助于抑制青少年的血压升高。参加者包括2185名最初年龄9至10岁的黑人和白人女孩，从1987年3月开始，持续随访了10年。在10年研究中的八年采用为期3天（两个工作日和一个周末日）的饮食记录对饮食进行了评估。没有证据表明，高钠摄入量（3000至<4000毫克/天和≥4000毫克/ 天比<2500毫克/天）对青少年血压有不利影响；且纵向混合模型表明，那些食用钠≥3500毫克/天与<2500毫克/天者相比，舒张压一般较低。然而，较高的钾摄入量与整个青春期血压变化和随访结束时的血压成反比。虽然钾钠比值与收缩压也成反比，相对于单独钾的效果而言，这些作用一般较弱。豆类，深色绿叶蔬菜，干果，鳄梨，酸奶，香蕉和鱼是钾的良好食物来源。来源：http://archpedi.jamanetwork.com/
