Mechanisms Underlying the Protective Vascular Effects of Dietary Potassium in Humans

Not Applicable

Recruiting

• Conditions: Cardiovascular Risk Factor
• Interventions: Other: High Potassium/High Sodium Diet; Other: Moderate Potassium/High Sodium Diet; Other: Moderate Potassium/Low Sodium Diet

• Registration Number: NCT04101188
• Lead Sponsor: University of Delaware

Brief Summary

Americans continue to consume high amounts of sodium. Potassium is notable for its blood pressure lowering effects but less is known regarding its effect on the vasculature. This investigation seeks to determine the role of dietary potassium on the vasculature in the presence of a high sodium diet in salt-resistant adults.

Detailed Description

Significant public health efforts have been made towards salt reduction but most have met with failure. Dietary factors such high sodium/low potassium diets contribute to the development of cardiovascular diseases (CVDs) such as atherosclerosis and high blood pressure (BP). This is important as CVD is the number one killer in the U.S. While the role of these two nutrients on BP is widely accepted, their impact on the vasculature has received less attention. Endothelial dysfunction, characterized by impaired dilation, is an important non-traditional risk factor for atherosclerosis. Evidence supporting potassium's beneficial role on vascular health remains unclear although it may be more effective in the presence of a high sodium diet. A purported mechanism responsible for sodium-induced vascular dysfunction is overproduction of reactive oxygen species (ROS) resulting in reduced nitric oxide (NO) production/bioavailability. Additionally, high sodium diets have been shown to stiffen the endothelium. This investigation will evaluate the vascular effects of dietary potassium during a high salt diet including its impact on sodium-induced oxidative stress and endothelial cell stiffness.

Study Timeline

• Study First Submitted: 2019-09-23
• Study First Submitted QC: 2019-09-23
• Study First Posted: 2019-09-24
• Study Start: 2020-01-16
• Status Verified: 2025-03
• Last Update Submitted: 2025-03-27
• Last Update Posted: 2025-04-02
• Primary Completion: 2025-07-31
• Study Completion: 2025-07-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 90

Inclusion Criteria

• healthy
• normal blood pressure
• normal resting ECG

Exclusion Criteria

• hypertension
• history of heart disease
• diabetes
• kidney disease
• obese (BMI ≥30)
• significant weight changes in the last 6 months
• use of tobacco products
• pregnant
• on a special diet (gluten free; vegan)
• take any medications for the above conditions
• endurance trained athletes

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
High Potassium/High Sodium	High Potassium/High Sodium Diet	Subjects will be provided with a diet that is high in both potassium and sodium.
Moderate Potassium/High Sodium	Moderate Potassium/High Sodium Diet	Subjects will be provided with a diet that is moderate in potassium and high in sodium.
Moderate Potassium/Low Sodium	Moderate Potassium/Low Sodium Diet	Subjects will be provided with a diet that is moderate in potassium and low in sodium.

Primary Outcome Measures

Name	Time	Method
Conduit artery endothelial-dependent dilation	on day 10 of the diet	The change in flow-mediated dilation (FMD) between the 3 diets as assessed by brachial artery FMD
Microvascular function	on day 10 of the diet	Cutaneous microvascular dilatory response to local heating assessed by laser Doppler flowmetry coupled with intradermal microdialysis

Secondary Outcome Measures

Name	Time	Method
Ambulatory BP monitoring	on day 7 and 10 of diet	assessed by 24-hour ambulatory blood pressure

Trial Locations

Locations (1)

University of Delaware; 🇺🇸 Newark, Delaware, United States