Effect of sodium and potassium supplementation on vascular and endothelial function: a randomized controlled trial

Abstract

Background: It is known that increased potassium and reduced sodium intakes can improve postprandial endothelial function. However, the effect of increasing potassium in the presence of high sodium in the postprandial state is not known. Objective: We aimed to determine the effect of high potassium and high sodium on postprandial endothelial function as assessed by using flow-mediated dilatation (FMD) and arterial compliance as assessed by using pulse wave velocity (PWV) and central augmentation index (AIx). Design: Thirty-nine healthy, normotensive volunteers [21 women and 18 men; mean 6 SD age: 37 6 15 y; BMI (in kg/m 2 ): 23.0 6 2.8] received a meal with 3 mmol K and 65 mmol Na (low-potassium, high-sodium meal (LKHN)], a meal with 38 mmol K and 65 mmol Na [high-potassium, high-sodium meal (HKHN)], and a control meal with 3 mmol K and 6 mmol Na (low-potassium, low-sodium meal) on 3 separate occasions in a randomized crossover trial. Brachial artery FMD, carotid-femoral PWV, central AIx, and blood pressure (BP) were measured while participants were fasting and at 30, 60, 90, and 120 min after meals. Results: Compared with the LKHN, the addition of potassium (HKHN) significantly attenuated the postmeal decrease in FMD (P-meal by time interaction , 0.05). FMD was significantly lower after the LKHN than after the HKHN at 30 min (P , 0.01). AIx decreased after all meals (P , 0.05). There were no significant differences in AIx, PWV, or BP between treatments over time. Conclusion: The addition of potassium to a high-sodium meal attenuates the sodium-induced postmeal reduction in endothelial function as assessed by FMD. This trial was registered at

Acute NaCl Loading Reveals a Higher Blood Pressure for a Given Serum Sodium Level in African American Compared to Caucasian Adults

“…These findings are important as they suggest that African American individuals may not be able to buffer acute Na + challenges as Caucasian individuals. These findings have important clinical implications: acute elevations in serum Na + (i.e., post-prandial) have a negative impact on the health of the vasculature ( Dickinson et al, 2011 , 2014 ; Suckling et al, 2012 ; Blanch et al, 2015 ), and our data demonstrate important racial differences in BP responsiveness. Thus, it is likely that repeated increases in BP responsiveness over time may contribute to the racial disparity in salt-sensitive hypertension.…”

“…These findings are of importance in light of (a) racial differences in the prevalence of salt-sensitive hypertension ( Williams et al, 2014 ; Fryar et al, 2017 ), and (b) the recent emphasis on plasma Na + concentration and BP in the literature ( He et al, 2005 ; He and Macgregor, 2012 ; Whelton et al, 2012 ). Additionally, several studies indicate that a single high Na + meal can similarly increase plasma Na + ( Dickinson et al, 2011 , 2014 ; Suckling et al, 2012 ; Blanch et al, 2015 ) and result in post-prandial reductions in endothelial functional ( Dickinson et al, 2011 , 2014 ; Blanch et al, 2015 ) and increases in BP ( Suckling et al, 2012 ). It has also been shown that young healthy African American females retain more Na + than young Caucasian females when placed on a high salt diet ( Palacios et al, 2004 ).…”

Dietary Potassium Attenuates the Effects of Dietary Sodium on Vascular Function in Salt-Resistant Adults

“…Salt-sensitive rodents supplemented with potassium while consuming a high salt chow were protected against vascular injury [10] and demonstrated improved left ventricular relaxation as assessed by echocardiography [11]. In regard to human studies, several acute interventions have shown potassium to have favorable vascular effects [14,36,37]. A high potassium meal improved FMD two hours post-prandially compared to a low potassium meal [37].…”

“…To date, studies that have evaluated the role of potassium on sodium have been acute and focused on the post-prandial changes in endothelial function. These studies have shown an attenuation of the post-meal reduction in endothelial function [14]. However, it is unknown if chronic dietary potassium intake can lessen the effect of high dietary sodium on the vasculature independent of BP changes.…”

Effect of Intermittent Energy Restriction on Flow Mediated Dilatation, a Measure of Endothelial Function: A Short Report

“…Increased dietary potassium intake from fruit and vegetables was shown to improve FMD within 1 week in healthy men and women ( p = 0.03) [ 36 ], and a 36-mmol potassium meal has been shown to attenuate postprandial reduction in FMD [ 37 ]. Further to this, it has been shown that the addition of potassium to a high-sodium meal improved the sodium-induced post meal reduction in endothelial function as assessed by FMD [ 38 ]. Continued research into the impacts of varying dietary composition, as well as length of time following the protocol prior to testing, on FMD would be beneficial.…”