Dietary Sodium and Blood Pressure

To the Editor. —Dr Midgley et al¹ suggested that a 100-mmol/d reduction in sodium intake would yield an average decrease in blood pressure of 3.7 mm Hg (systolic) and 0.9 mm Hg (diastolic) in hypertensive individuals and 1.0 mm Hg (systolic) and 0.1 mm Hg (diastolic) in normotensive individuals and then questioned the wisdom of current recommendations for moderation in sodium intake in the general population. As the authors point out, many of the 56 trials that formed the basis for their meta-analysis were of questionable quality. Furthermore, the median length of intervention was only 14 days, which is considerably less than desirable for implementation of a behavior change intervention and too short to observe the full effects of a meaningful reduction in sodium intake on blood pressure. As a consequence, the analysis is heavily weighted by results from studies of doubtful relevance to the question at hand. Greater reliance should be