Journal of the American Heart Association, 2020 · Dose-response meta-analysis of RCTs
Across 32 trials, extra potassium lowered blood pressure most in people with hypertension and in those eating more salt, but the relationship was U-shaped: the benefit faded above about 30 mmol (1.2 g) a day extra, and at much higher doses blood pressure rose again in people taking blood-pressure medication. Estimates for high intakes rest on few trials.
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