Global health outcomes from replacing dietary sodium chloride with potassium-enriched salt

ABSTRACT Objective To estimate the benefit and risk of replacing regular salt with potassium-enriched salt. Design Comparative risk assessment modelling. Setting Worldwide Participants Adult populations aged 25 and above. Intervention (1) worldwide replacement of all salt (discretionary salt used for seasoning or cooking in the home, and non-discretionary salt used in processed and restaurant foods); (2) worldwide replacement of just discretionary salt; (3) worldwide replacement of just non-discretionary salt; (4) replacement of discretionary salt just for people with diagnosed hypertension; and (5) replacement of discretionary salt just for people with treated hypertension. Main outcome measures For scenarios 1-3, we estimated benefits including deaths, new cases and disability-adjusted-life-years (DALYs) from cardiovascular disease and chronic kidney disease (CKD), from blood pressure-lowering as well as harms (CVD deaths) caused by hyperkalaemia among people with CKD stages G3-G5. Results Replacement of all salt worldwide could prevent 2.96 (95% uncertainty interval 2.81-3.12) million deaths, 10.17 (9.59-10.70) million new cases of disease and 69.43 (65.61-72.92) million disability-adjusted life years (DALYs) each year. These figures represent 14.6%, 13.1% and 16.5% of the annual global disease burden attributable to CVD and CKD. Replacement of all discretionary salt (1.85, 1.74-1.97 million deaths) would have a greater impact on mortality than replacement of all non-discretionary salt (1.56, 1.46-1.67 million deaths). In people with CKD Stage G3-G5, there would be a net benefit - replacement of all salt would prevent 0.75 (0.71-0.80) million deaths but might cause 0.10 (0.09-0.11) million deaths from hyperkalaemia. Discretionary salt replacement only among diagnosed or treated hypertensives would prevent 0.59 (0.55-0.63) million and 0.48 (0.45-0.52) million deaths, respectively. Conclusion Switching regular salt to potassium-enriched salt appears to offer large potential for health gains under diverse scenarios, including for people with CKD. Funding This work did not receive specific funding. What is already known on this topic - Excess dietary sodium and low dietary potassium intake both cause high blood pressure, which causes a significant burden of cardiovascular disease (CVD) and chronic kidney disease (CKD). - Efforts to cut dietary sodium intake as a strategy to control blood pressure have mostly been unsuccessful, with no country expected to meet the World Health Organisation (WHO) 2025 goal of reducing sodium intake by 30%. - Switching regular salt to potassium-enriched salt has shown clear protection against CVD and causes minimal change in taste and has low cost to scale up, but concerns remain about the potential of causing deaths due to hyperkalaemia among people with advanced chronic kidney disease. What this study adds - The study modelled five different possible approaches to the implementation of potassium-enriched salt that will suit a range of different circumstances, including countries with different levels of discretionary versus non-discretionary salt intake. - The study indicates switching to potassium-enriched salt can prevent very large numbers of CVD and CKD events worldwide, while the potential for causing harm in people with CKD is small in comparison. - There was also net benefit in analyses restricted to just people with CKD, where benefits of blood pressure lowering outweigh potential harms from hyperkalaemia.