Because of the overwhelming effect of sodium, as reflected in the high prevalence of hypertension in South Africans, the South African Department of Health is in the process of implementing a nationwide sodium reduction strategy, which will come into effect in June 2016. An establishment of a data platform which will provide a basis for the on-going monitoring of the impact of the proposed sodium reduction regulation, is much needed. The overall purpose of this research paper is the establishment of the 24-hour sodium excretion of three different populations divergent in geographical regions to provide a baseline of the sodium (salt) intake of South Africans prior to the reduction legislation.Design and method:
We obtained data from three on-going studies between the periods of 2013 to 2015. One of the studies is a prospective 10-year study and the other two was cross-sectional of nature. In total, data was collected from 693 White, Black and Indian individuals. 24-hour urine collections were done according the WHO standards. Sodium and potassium were analysed by means of ion-selective electrode potentiometry on the Cobas Integra® 400 plus (Roche, Basal Switzerland).Results:
The mean sodium and potassiumin excretion of the population was 152.1 mmol/day (3498 mg/day OR 8.7 g salt/day) and 43.4 mmol/day (1692 mg/day) respectively. Overall men had higher sodium as well potassium excretion than women (p = 0.001). The Black population showed higher sodium and potassium excretion compared to Whites and Indians (p = 0.003). Sodium excretion is the highest in men under the age of 30 years (172.7 mmol/day). The highest potassium (51.6 mmol/day) and sodium (200.8 mmol/day) excretion were observed in men with a BMI of above 30 kg/m2. The mean Na:K in this study is 2:3.Conclusions:
Only 7.2% of the population is reaching the recommended potassium intake of 90 mmol/day. With regards to the sodium excretion, 76.2% of the population is above the recommended 86 mmol/day. This research supports the governement's initiave of implementing a sodium reduction legislation and provides valuable information with regards to South African's salt intake and the effect it will have on the public health system in terms of blood pressure.