The Role of Dietary Sodium and Potassium on Sleep Quality and Sleep Duration

• Douglas Patrick, Medical Diagnostics, University of Delaware

• Shannon Lennon, Kinesiology & Applied Physiology, University of Delaware

High sodium diets negatively affect cardiovascular health by increasing blood pressure (BP) while potassium has been shown to lower BP. Improved sleep quality is also associated with a lower BP. The objective of this study was to investigate the role of dietary sodium and potassium on sleep quality and sleep duration. We hypothesized that a high sodium/low potassium (HS/LK) diet would decrease sleep quality, sleep duration and sleep efficiency compared to the low sodium/low potassium (LS/HK) and high sodium/high potassium (HS/HK) diets. Healthy men and women aged 18-45 years with a normotensive BP were recruited to participate in a controlled feeding study. Participants consumed three 10-day prepared diets containing: LS/LK (50/65 mmol), HS/LK (300/65 mmol) and HS/HK (300/120 mmol) in a randomized order. On day 9, participants wore a BP monitor for 24 hours, and on day 10 they completed the Pittsburgh Sleep Quality Index (PQSI) and Munich sleep questionnaires. Thirty-nine normotensive adults (23M/16F, 30±7 yrs, BMI: 24.55±4.6; 106±8/68±6 mmHg) participated. There was no difference in mean arterial pressure between the 3 diets (p>0.05). Sleep quality as determined by the PSQI was not different between diets (LS/LK: 4.21±3.01; HS/LK: 4.05±2.94; HS/HK: 4.44±2.99; p=0.85). Average sleep duration assessed by the Munich was also not different between diets on workdays (LS/LK: 8.00±1.23hrs; HS/LK: 7.74±1.20hrs; HS/HK: 7.92±1.2hrs, p=0.628) as was sleep efficiency and sleep midpoint (p>0.05). In conclusion, a high sodium/low potassium diet did not alter sleep quality and sleep duration in comparison to a low sodium/high potassium diet or a high sodium/high potassium diet.