Can We End the Salt Wars With a Randomized Clinical Trial in a Controlled Environment?

Abstract

The 2013 Institute of Medicine (IOM; now the National Academy of Medicine) Report: Sodium intake in populations recommended that “clinical trials might focus on examining the effects of a range of sodium levels on risk of cardiovascular events, stroke, and mortality among patients in controlled environments.”1 This recommendation was specific in 2 regards. It recommends a cardiovascular outcomes trial of dietary sodium reduction, and it recommends this be done in people in controlled environments. There are important reasons behind these specific recommendations. Despite the large body of data on the relationship between cardiovascular disease and dietary sodium from observational studies and the positive impact on blood pressure in randomized controlled clinical trials and current national guidelines recommending daily sodium intakes of ≤2300 mg/d, mean daily intake for Americans remains in the 3400 to 3500 mg/d range.2 Some scientists have questioned the justification for a reduced intake of dietary sodium.3 This disagreement within the scientific community has been reported in the lay press, leading both clinicians and some in the public to express uncertainty on the issue.4–6 The IOM is not alone in calling for an outcomes clinical trial on dietary sodium. The World Heart Federation, the European Society of Hypertension, and the European Public Health Association joined together to call for a definitive clinical trial of sodium restriction.7 Indeed, for years, leading voices in this area of research have noted the absence of evidence from an outcomes-based clinical trial and advocated for execution of such a trial. The reason this trial has not been accomplished can be seen in the second specificity of the IOM recommendations: that the trial be performed in “patients in controlled environments.” This statement recognizes the …