Low sodium diet after DASH: has the situation changed? Dietary Approaches to Stop Hypertension

The Dietary Approaches to Stop Hypertension (DASH) trial adds to the large body of evidence indicating a direct association of dietary sodium with blood pressure, and showing that rigorous reduction of dietary sodium can reduce blood pressure over a 30-day period by statistically significant amounts. DASH, however, neither addressed nor answered whether a reduction of dietary sodium reduces morbidity and mortality. Data linking baseline sodium to mortality and morbidity outcomes are sparse, with only six known studies. Of these, two showed no association, two showed an inverse association, and two showed a direct association only in obese subsets. No studies have examined outcomes after sodium reduction, and no studies have linked sodium to outcomes or even a blood pressure benefit among treated hypertensives. Universal recommendations for sodium reduction or dietary sodium goals should await evidence that such interventions are both safe and effective as measured by morbidity and mortality outcomes.