Small reductions in blood pressure (BP) on a population level could have a substantial impact on cardiovascular disease risk.1 This is especially relevant considering that the majority of the population has suboptimal BP levels. Dietary sodium reduction is a clearly established lifestyle change that has great potential to improve public health. Potassium, on the contrary, received much less attention. Nevertheless, a substantial body of data shows that increasing potassium intake lowers BP.2 We reviewed population data on potassium intake and estimated the potential impact of increased potassium intake on population BP levels.
We searched PubMed and contacted health authorities worldwide for national population-based dietary surveys conducted from 1990 to 2009 that included data on potassium intake in more than 1000 adults. We defined the recommended level of potassium intake at 4.7 g/d, based on the Dietary Reference Intakes from the Institute of Medicine.2 The effect of dietary potassium on systolic BP was set at 1.0–mm Hg reduction per 0.6 g/d increase in intake, based on estimates from the INTERSALT study,3 and we assumed this relation to be linear. Population BP data were obtained for Finland, the United Kingdom, and the United States, representing populations with relatively high, medium, and low potassium intakes.4-7 For these countries we estimated the potential impact of increasing potassium intakes on population systolic BP levels and classification in different systolic BP categories, assuming a uniform shift in the population BP distribution, independent of initial BP level.