Potassium-Enriched Salt Substitutes as a Means to Lower Blood Pressure: Benefits and Risks

Use of salt substitutes containing potassium chloride is a potential strategy to reduce sodium intake, increase potassium intake, and thereby lower blood pressure and prevent the adverse consequences of high blood pressure. In this review, we describe the rationale for using potassium-enriched salt substitutes, summarize current evidence on the benefits and risks of potassium-enriched salt substitutes and discuss the implications of using potassium-enriched salt substitutes as a strategy to lower blood pressure. A benefit of salt substitutes that contain potassium chloride is the expected reduction in dietary sodium intake at the population level because of reformulation of manufactured foods or replacement of sodium chloride added to food during home cooking or at the dining table. There is empirical evidence that replacement of sodium chloride with potassium-enriched salt substitutes lowers systolic and diastolic blood pressure (average net Δ [95% CI] in mm Hg: -5.58 [-7.08 to -4.09] and -2.88 [-3.93 to -1.83], respectively). The risks of potassium-enriched salt substitutes include a possible increased risk of hyperkalemia and its principal adverse consequences: arrhythmias and sudden cardiac death, especially in people with conditions that impair potassium excretion such as chronic kidney disease. There is insufficient evidence regarding the effects of potassium-enriched salt substitutes on the occurrence of hyperkalemia. There is a need for additional empirical research on the effect of increasing dietary potassium and potassium-enriched salt substitutes on serum potassium levels and the risk of hyperkalemia, as well as for robust estimation of the population-wide impact of replacing sodium chloride with potassium-enriched salt substitutes.