Effects of salt substitutes on clinical outcomes

Trial evidence demonstrates that reduced dietary sodium consumption or potassium supplementation lowers blood pressure:

• sodium-reduced, potassium-enriched salt substitutes, in which a proportion of the sodium chloride (NaCl) in regular salt is replaced with potassium chloride (KCl), combine these blood pressure-lowering effects (1)

A review of 21 trials (n=31,949) found use of salt substitutes (e.g. potassium enriched substitutes) reduced systolic and diastolic blood pressure by 4.61 and 1.61mmHg respectively, and reduced overall (RR 0.89, 95%CI 0.85-0.94) and CV (0.87, 0.81-0.94) mortality (1)

• prior systematic reviews of salt substitutes have reported clear beneficial effects on blood pressure levels, but effects on clinical outcomes and the risk of premature death have been ill-defined due to sparse data
• study authors concluded that:
  • beneficial effects of salt substitutes on blood pressure across geographies and populations were consistent. Blood pressure-mediated protective effects on clinical outcomes are likely to be generalisable across population subgroups and to countries worldwide.

In 2021, the Salt Substitute and Stroke Study (SSaSS) (3) demonstrated a significant reduction in BP, CVD, and death among Chinese adults randomized to a low sodium salt-substitute supplemented with potassium. This trial largely puts to rest any remaining debate about the benefits of dietary sodium restriction among persons with excess baseline intake (dietary sodium intake fell from approximately 5 down to 4 g/day in the active arm of SSaSS).

Reference:

1. Yin X et al. Availability, formulation, labeling, and price of low-sodium salt worldwide: environmental scan. JMIR Public Health Surveill 2021;7:e27423.
2. Yin X, Rodgers A, Perkovic A, et al. Effects of salt substitutes on clinical outcomes: a systematic review and meta-analysis.Heart Published Online First: 09 August 2022.
3. Neal B et al. Effect of Salt Substitution on Cardiovascular Events and Death. N Engl J Med 2021;385:1067-1077