Effect of South Africa’s interim mandatory salt reduction programme on urinary sodium excretion and blood pressure

Abstract

Highlights Thirty percent reduction in population salt intake by 2025 is recommended by WHO. South Africa introduced mandatory maximum sodium limits in processed foods in 2016. A countrywide impact evaluation assessed change in salt intake after two years. Salt intake measured using 24hr Na excretion dropped by 1.15 g per day. Ongoing evaluation is necessary as more stringent targets were implemented in 2019.

Will Food and Drug Administration Guidance to Reduce the Salt Content of Processed Foods Reduce Salt Intake and Save Lives?

“…14 A statistically significant reduction in salt intake could be shown only after adjusting the salt intake data for nearly a dozen other variables. 14 Alarmingly, the introduction of mandatory food salt targets in South Africa was also associated with a significant increase in diastolic blood pressure, a significant decrease in potassium intake (as judged by urinary potassium measurements), and no change in systolic blood pressure. 14 In summary, when evaluating the predictions of the interesting modeling studies by Song et al, it is important to understand the impact of food salt reduction on salt consumption in high income countries like England and the United States.…”

“…South Africa is one of the only other countries in which salt intake has been assessed by measurements of 24-hour urine sodium excretion before and after introducing a food salt reduction program. 14 A statistically significant reduction in salt intake could be shown only after adjusting the salt intake data for nearly a dozen other variables. 14 Alarmingly, the introduction of mandatory food salt targets in South Africa was also associated with a significant increase in diastolic blood pressure, a significant decrease in potassium intake (as judged by urinary potassium measurements), and no change in systolic blood pressure.…”

“… 14 Alarmingly, the introduction of mandatory food salt targets in South Africa was also associated with a significant increase in diastolic blood pressure, a significant decrease in potassium intake (as judged by urinary potassium measurements), and no change in systolic blood pressure. 14 …”

Delayed Finalization of Sodium Targets in the United States May Cost Over 250 000 Lives by 2031

“…24 Another example is South Africa’s mandatory maximum sodium targets for certain processed foods implemented since 2016, which was associated with a decline of 460 mg/d in mean population sodium intake over the following 2 years (measured by 24-hour urinary excretion). 22…”

“…Setting sodium-reduction targets for packaged foods has been shown to have the potential to both spur industry to lower the sodium content in processed foods and reduce the population sodium intake in some countries. 22,23 For example, beginning in 2006, the United Kingdom established progressively lower voluntary sodium (mostly from sodium chloride) targets for over 80 food categories, provided clear timetables to encourage ongoing food reformulation, and monitored the progress of sodium reduction by industry. As a result, population sodium intake measured by 24-hour urinary excretion declined by 10% between June 2005 (geometric mean [95% CI, 2989 (1013–8822)] mg/d; arithmetic mean [95% CI, 3304 (69–6539)] mg/d) and 2011 (2714 [1020–7221] mg/d; 2989 [494–5484] mg/d).…”