The effect of low-dose potassium supplementation on blood pressure in apparently healthy volunteers

Epidemiological and clinical trials suggest an inverse relationship between dietary K intake and blood pressure (BP). Most trials however have been of short duration, the dose of K was high, and the results have been conflicting. The aim of the present study was to evaluate the effect on BP of a low-dose supplementation (24 mmol/d) for an extended period. A double-blind placebo-controlled trial was conducted on fifty-nine volunteers, randomly assigned to receive 24 mmol slow-release KC1/d (n 30) or a placebo (n 29). Measures of BP, anthropometric characteristics and urine analysis for electrolytes were recorded during a 1-week baseline period. Supplementation was for 6 weeks during which BP and changes in weight were assessed and a second 24h urine collection made. The primary outcome was the change in mean arterial pressure (MAP); systolic BP(SBP) and diastolic BP(DBP) were secondary outcomes. After 6 weeks of supplementation MAP was reduced by 7·01 (95% CI −9·12, −4·89; PPPP