A simple salt swap could prevent nearly 3 million deaths a year, researchers estimate

What happens when the world's salt supply gets a potassium-rich makeover? Researchers examined the potential impact on heart and kidney health across 193 countries, including the risks for people with impaired kidney function.

Study: Global health outcomes from replacing dietary sodium chloride with potassium-enriched salt. Image Credit: New Africa / Shutterstock

A recent modeling study published in the journal Nature Health estimated that replacing regular salt with a potassium-enriched, sodium-reduced salt substitute worldwide could prevent nearly three million deaths and 10 million new cases of cardiovascular disease (CVD) and chronic kidney disease (CKD) annually.

A blend of 25% potassium chloride (KCl) with 75% sodium chloride (NaCl) could also avert more than 69 million disability-adjusted life years (DALYs). The model also projected additional hyperkalemia-related deaths among people with CKD stages G3–G5, but estimated that the reduction in blood pressure (BP) could prevent many more deaths.

The findings highlight potassium-containing salts as a practical strategy to reduce the global burden of non-communicable diseases. CVD and CKD contribute to considerable morbidity and mortality worldwide. Hypertension, or high BP, is a modifiable risk factor for both conditions. Reducing salt intake and increasing potassium consumption may lower BP, reducing the risk of CVD and CKD and improving outcomes among people already living with these conditions.

About the study

Scientists at the George Institute for Global Health and the University of New South Wales in Sydney, Australia, led the research in collaboration with researchers from institutions in the United States, the Netherlands, China, the United Kingdom and Sweden.

The team modeled the potential health effects of replacing regular salt with potassium-enriched alternatives among approximately 4.63 billion adults aged 25 years and older across 193 countries and territories.

The study examined three scenarios: replacing all dietary salt; replacing only salt used in home cooking and seasoning; or replacing only salt found in processed and restaurant foods. They also investigated whether limiting discretionary salt replacement to people with diagnosed or treated hypertension could alter the estimates, assuming clinicians would advise 20% of these patients against using potassium-enriched salt because of potential risks. Only BP-related benefits were modeled for these groups because clinical screening was assumed to exclude patients with CKD stages G3–G5.

The team also estimated mortality under scenarios in which 20%, 50%, or 100% of regular dietary salt was replaced with the potassium-enriched substitute. Sensitivity analyses examined alternative assumptions about the dose–response relationship between sodium restriction and systolic blood pressure (SBP).

The team also tested the additive BP-lowering impact of limiting sodium intake and increasing potassium intake when these effects were reduced to 80% of their original magnitude.

Another scenario halved the estimated BP-lowering effect of increased potassium intake. Additional scenarios assumed no potassium-related BP benefits among non-hypertensive individuals, evaluated a substitute containing 15% KCl and 85% NaCl, and assessed whether BP-lowering effects plateaued below separate daily sodium thresholds of 2.5 and 3.0 grams.

The team obtained country-specific sodium intake estimates and country-, age-, and sex-specific estimates of SBP, CKD and CVD burden, and CKD stages G3–G5 prevalence from the 2021 Global Burden of Disease (GBD) study, supplemented by other research. Discretionary and non-discretionary sources of dietary salt were estimated using a GDP-based regression model with updated 2021 World Bank or International Monetary Fund data.

Hypertension prevalence and treatment rates came from the 2019 Non-Communicable Disease Risk Factor Collaboration, while associations between SBP changes and CVD or CKD risks were based on the 2019 GBD study.

Results

Replacing all regular salt with a potassium-containing salt worldwide could avert 10.17 million incident cases, 2.96 million net deaths (95% uncertainty interval, 2.81–3.12 million) (after accounting for the estimated deaths caused by hyperkalemia), and 69.43 million DALYs annually from CVD and CKD.

Estimates for new cases and DALYs reflected benefits mediated through BP reduction only. These estimates correspond to approximately 15% of annual CVD and CKD deaths, 13% of new cases, and 17% of DALYs worldwide.

India and China had the largest projected absolute benefits. In 133 of 193 countries, predominantly in North America, Latin America, and Asia, using potassium-based alternatives could prevent at least 10% of cardiovascular deaths. Women accounted for approximately 40% of these benefits, with similar findings across intervention scenarios.

Replacing salt added during home cooking and seasoning alone was estimated to prevent 1.85 million deaths, representing 63% of the reduction achieved when the intervention also included salt in processed and restaurant foods. This represents 9.2% of annual CKD and CVD deaths.

Replacing discretionary use was projected to prevent more fatalities than replacing non-discretionary use (1.56 million), especially in India, China, Russia, and Indonesia. In the United States and Europe, processed and restaurant foods account for more than 70% of salt intake, making non-discretionary replacement particularly relevant.

Targeting discretionary salt replacement among 658 million individuals with a hypertension diagnosis would avert 0.59 million deaths, whereas targeting 523 million receiving treatment for hypertension was estimated to avert 0.48 million deaths. Among individuals with CKD stages G3–G5, replacing all dietary salt could prevent 0.75 million cardiovascular deaths through BP reduction but potentially result in 0.10 million hyperkalemia-related deaths.

The authors cautioned that increased hyperkalemia-related mortality has not been demonstrated in clinical trials and might be overestimated because the model assumed that at-risk patients were not excluded from population-wide replacement.

According to the estimates, replacing 20% of all regular dietary salt could prevent 0.7 million deaths, whereas 50% substitution would avert 1.72 million deaths. Across sensitivity analyses, the projected number of deaths prevented ranged between 2.02 and 2.72 million. Assuming that CKD stages G3–G5 were more prevalent in hypertensive adults from low- and middle-income countries (LMICs) slightly reduced the projected health benefits, but considerable gains remained across populations.

Maps illustrate the median annual number of net deaths averted following replacement of regular salt (100% NaCl) with potassium-enriched salt (75% NaCl and 25% KCl) under different implementation scenarios. Net deaths averted were calculated as deaths prevented through blood pressure reduction minus deaths attributable to hyperkalaemia among individuals with stage G3–G5 CKD. Median estimates were derived from 1,000 Monte Carlo simulations. Basemaps from Natural Earth (http://www.naturalearthdata.com).

Conclusion

The findings suggest that potassium-based alternatives to regular salt could prevent over 13 million combined deaths and new cases of CKD and CVD and avert 69 million DALYs annually under a hypothetical worldwide switch.

Combining sodium reduction with increased potassium intake may offer greater benefits than sodium reduction alone. These projections reflect a single point in time and rely on assumptions about dietary intake and BP responses. Worldwide implementation could take decades, so the projected health gains would not be immediately achievable. Higher prices, product availability, and adoption by the food industry pose further challenges.

Potassium-enriched salt may also offer a practical alternative for people who find low-sodium diets difficult to follow because of taste preferences. Increased potassium intake can raise the risk of hyperkalemia, especially in people with CKD.

The findings highlight the need for cautious use under healthcare supervision, improved CKD screening, clear product warnings, and transparent potassium content labeling on packaged foods.

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