 Background The global burden of hypertension is huge. The estimated number of adults with hypertension in the year 2000 was 972 million and this number is expected to increase by about 60 to a total number of 1.56 billion in 2025 worldwide 1. In Denmark, the estimated prevalence of hypertension among the adult population lies between 26 and 40 2. Hypertension is thus a wide spread disease and it is further known, that hypertension is one of the most important modifiable risk factors for cardiovascular, cerebrovascular and renal disease 3;4. In this study we investigate the role of potassium in the regulation of the human blood pressure. 