Sodium and Potassium Intake of Urban Dwellers: Nothing Changed in Yazd, Iran

To assess the daily salt intake of people aged 20-74 years based on the 24-hour urinary sodium excretion in urban population of Yazd, a population-based cross-sectional study was conducted. This is a substudy of Yazd Healthy Heart Project in Iran. From 2004 to 2005, two thousand people of the urban population of Yazd city, aged 20-74 years, were enrolled in the main study. Overall, 219 volunteer participants of 20-70 years were enrolled in this substudy. Sample frame was the household numbers according to the database of Yazd City Health Services. Calcium, phosphorus, sodium, potassium, and creatinine were measured in the urine samples collected from the participants over a 24-hour period. Sodium content in urine over 24 hours was 171.7±82.9 mmol/day in males and 127.8±56.1 mmol/day in females (p<0.0001) while potassium content was 49.4±23.2 mmol/day in males and 41.5±25.1 mmol/day in females (p=0.2). Estimated average daily salt (NaCl) intake was 10.0±4.8 g/day in males and 7.5±3.3 g/day in females (p<0.0001). Only one participant had the ideal Na/K ratio of less than one. Na/K ratios greater than one and less than two were seen in 11.3% (n=24), and a ratio equal to or greater than 2 was observed in 82.3% (n=118) of the participants. The average Na/K ratio was 3.69±1.58. Unlike many developed countries where sodium intake declined over the past few decades, the daily sodium intake in Yazd is high, and daily potassium intake is low. This is similar to what was observed four decades ago in an area not far from Yazd. Efforts must be directed towards health promotion interventions to increase public awareness to reduce sodium intake and increase potassium intake.

Keywords
24-hour urine; Blood pressure; Cardiovascular disease; Hypertension; Policy; Potassium; Prevention; Salt; Sodium; Iran