Background: Potassium supplementation has emerged as a promising strategy to reduce blood pressure and cardiovascular disease (CVD) risk. However, uncertainties remain regarding optimal dosing, forms of potassium, and strength and consistency of the effect of potassium supplementation on hard CVD outcomes such as CVD death. Objective: To systematically map the existing evidence on potassium supplementation—with and without sodium reduction—on CVD outcomes in adults, identifying gaps to inform future clinical guidelines and research priorities. Methods: We systematically reviewed recent evidence on potassium supplementation and cardiovascular outcomes, including morbidity and mortality, searching Medline and Cochrane Central for articles published between January 2018 to June 2025. Eligible exposures included potassium supplementation (e.g., chloride, bicarbonate, citrate, gluconate, lactate, nitrate, phosphate, magnesium citrate, and enriched foods) with or without sodium reduction. Outcomes of interest included intermediary endpoints (i.e., blood pressure, arterial stiffness, coronary artery calcification) and hard endpoints (e.g., incident hypertension, cardiovascular morbidity and mortality). Minimum follow-up was ≥4 weeks for intermediary and ≥12 months for hard endpoints. Full text screening and data extraction is ongoing and performed by independent reviewers. Data will be synthesized into an interactive map using EPPI-Mapper. Results: We reviewed 6,392 unique citations with 22 meeting inclusion criteria. Twelve studies examined the effect of salt substitutes on cardiovascular health. Studies of supplemental potassium chloride and potassium nitrate were also identified with one study examining potassium-enriched foods. The evidence suggested an association between potassium supplementation and reduced CVD risk with most citations ( n =18) utilizing a randomized design. There were few studies on the effect of potassium on arterial stiffness and coronary artery calcification and few among healthy populations and those with chronic kidney disease. Conclusion: This evidence and gap map provides an overview of the current evidence for potassium supplementation and CVD outcomes. Findings will inform the need for a full systematic review and potential updates to chronic disease risk reduction recommendations. The results are expected to have significant implications for clinical practice, public health guidance, and future research agendas.
Cheng et al. (Tue,) studied this question.