Dietary sodium and potassium have been shown to affect blood pressure (BP) but their influence on BP variability (BPV) is less studied as is the influence of sex. The aim of this study was to compare 24 h BP and short-term BPV in response to varying dietary levels of sodium and potassium in healthy non-obese normotensive salt-resistant adults. We hypothesized that high sodium would increase short-term BP and BPV while the addition of high potassium would counteract this increase. Furthermore, we hypothesized that women would experience greater increases in BPV under high sodium conditions compared to men while potassium would attenuate this response. Thirty-seven participants (17 M/20 W; 27 ± 5 years old; BMI 24.3 ± 3 kg/m²) completed seven days each of the following randomized diets: moderate potassium/low sodium (MK/LS), moderate potassium/high sodium (MK/HS) and high potassium/high sodium (HK/HS). BP and short-term BPV were assessed using 24 h ambulatory BP monitoring starting on day 6. BPV was calculated using the average real variability (ARV) index. Twenty-four hour, daytime, and nighttime systolic BP (SBP) were lower in women compared to men regardless of diet. However, 24 h and daytime SBP were lowered in women on the HK/HS diet compared to the MK/HS diet. There were no significant effects of diet or sex for 24 h, daytime or nighttime SBP ARV. However, men exhibited a higher 24 hDBP ARV than women regardless of diet. In conclusion, a high potassium diet lowered BP under high sodium conditions in women alone while men exhibited higher short-term BPV that was not influenced by diet.

饮食中的钠和钾已被证明会影响血压 (BP)，但它们对血压变异性 (BPV) 的影响以及性别的影响研究较少。本研究的目的是比较健康非肥胖、正常血压耐盐成人的 24 小时血压和短期血压值对不同钠和钾饮食水平的反应。我们假设高钠会增加短期血压和血压值，而添加高钾会抵消这种增加。此外，我们假设与男性相比，在高钠条件下女性的 BPV 会增加更多，而钾会减弱这种反应。37 名参与者（17 M/20 W；27 ± 5 岁；BMI 24.3 ± 3 kg/m ²）完成以下随机饮食各 7 天：中钾/低钠 (MK/LS)、中钾/高钠 (MK/HS) 和高钾/高钠 (HK/HS)。从第 6 天开始，使用 24 小时动态血压监测评估血压和短期 BPV。BPV 使用平均真实变异性 (ARV) 指数计算。无论饮食如何，女性的 24 小时、白天和夜间收缩压 (SBP) 均低于男性。然而，与 MK/HS 饮食相比，HK/HS 饮食的女性 24 小时和白天收缩压较低。饮食或性行为对 24 小时、白天或夜间 SBP ARV 没有显着影响。然而，无论饮食如何，男性的 24 hDBP ARV 均高于女性。总之，高钾饮食可降低女性在高钠条件下的血压，而男性则表现出较高的短期血压值，且不受饮食影响。