Nutrient intake timing and exercise timing is associated with blood pressure

Background and objectives: cardiovascular diseases (CVDs) are one of the leading causes of death worldwide, and one of the most significant risk factors for CVDs is high blood pressure (BP). BP is associated with the intake of various nutrients, such as sodium, potassium, and cholesterol. However, research focusing on intake timing of these nutrients and BP has not been conducted. Furthermore, while physical activity has been suggested to take part in BP reduction, their timing effects also remain unclear. Therefore, we conducted two studies with the aim of hypertension prevention; (1) when each nutrient should be taken and (2) when exercise should be done. Methods: (1) We used dietary data and a questionnaire asking about sleep, physical activity, and BP, collected from the food-log app "Asken" (N=2402), to investigate the relationship between the dietary data of nutrient intake in the breakfast, lunch, and dinner and BP.(2) We used questionnaire asking about the participants' systolic and diastolic blood pressure and weekly physical activity situation (length, frequency, intensity, and timing) to conduct analysis on their relationship (N=2343). Results: (1) Daily total intake of various nutrients such as sodium, sodium-to-potassium ratio, potassium, total energy, lipid, carbohydrate, and saturated fat showed a significant association with BP depending on the meal timing. From multiple regression analysis, eliminating the confounding factors, lunch sodium-to-potassium ratio, dinner energy, lipid, cholesterol, saturated fat, and alcohol intake were positively associated with systolic BP, whereas breakfast protein and lunch fiber intake showed a negative association. (2) Total physical activity, walking time and frequency, vigorous evening exercise (18:00-21:00) showed strong negative association with both systolic and diastolic BP. When participants were divided into groups according to the BP categories, compared to normal BP groups, higher BP groups exercised less in the evening. Conclusions: Our results suggest that nutrient intake and exercise timing are important factors in the prevention of high BP. Our study provides possibilities to prevent hypertension by changing the timing of nutrient intake, especially sodium, together with potassium and lipids and by exercising in the evening. However, further research on the general population needs to be conducted.