For the purpose of short term clinical trials previous studies have made use of metabolic kitchens to provide severely restricted sodium diets. We evaluated the feasibility of administering a 5-day severely restricted (22 mmol) sodium diet on an outpatient basis with counselling support, outside a metabolic unit. In 13 highly-motivated volunteers, 24-h urinary sodium excretion fell from 128.5 +/- 11.9 on a normal diet to 19.2 +/- 2.88 mmol per day and plasma sodium dropped from normal diet to 19.2 +/- 2.88 mmol per day and plasma sodium dropped from 140 +/- 0.41 to 137 +/- 0.78 mmol/L, showing that such an approach is effective.