Estimate of total salt intake in two regions of Belgium through analysis of sodium in 24h urine samples

Objectives: To evaluate total salt intake in the adult population through an analysis of sodium in 24-h urine samples in two regions of Belgium.

Methods: Urine samples were collected over 24 h from participants and they had to complete a specific questionnaire about salt intake afterwards. Sodium and creatinine concentrations were analysed in these samples.

Subjects: The target population comprised adults aged 45–65 years in the region of Ghent and Liege. A total of 123 and 157 volunteers from Ghent and Liege, respectively, were included in the study.

Results: The mean creatinine level in Flanders (n=114) amounted to 0.173±0.035 mmol/kg/day, whereas in the Walloon region (n=135) it amounted to 0.161±0.036 mmol/kg/day, after the exclusion of subjects with incomplete urine collection. Intake of sodium in Flanders (n=114) was 4.29±1.29 g/day, whereas in the Walloon region (n=135) it was 3.94±1.44 g/day. In both regions, sodium intake in men was higher than in women.

Conclusion: Salt intake was more or less twice as high as the recommended intake. Salt intake as estimated from 24-h urine collections is substantially higher than that previously calculated on the basis of food consumption data. A salt reduction programme for Belgium is primordial.