Table 1.

Important Issues That Could Be Addressed in Setting Standards for Research on Sodium (Salt) Intake and Health

The assessment of dietary sodium intake for populations or for individuals is precise and reliable.

The method for assessing outcomes (eg, blood pressure and cardiovascular disease) is robust and there is minimum loss to follow‐up.

Intervention studies have a substantive and sustained impact on sodium intake, and in observational studies there is a substantive difference between low and high sodium intake.

The study has a duration relevant to the health and disease outcomes under investigation.

The study has adequate statistical power to address the reported outcomes.

Relevant confounding factors are assessed, reasonably balanced, and accounted for in design and analysis.

Blood pressure, which is on the causal pathway, is not adjusted for in analyses of effects on clinical outcomes.

The right study designs are used to assess the question under evaluation. Specifically, it is not clear whether further retrospective studies of the relationship between sodium and either blood pressure or vascular events are warranted. Likewise, further cohort studies of the relationship between sodium and either blood pressure or vascular outcomes may not be helpful, particularly when the studies are performed in populations of patients with preexisting disease, in whom the risks of reverse causality are profound.

Steps are taken to minimize the impact of reverse causality in cohort studies with patients who have existing disease. In such settings, reverse causality is always discussed as a major limitation precluding definitive conclusions.

Drugs (especially diuretics) and other factors that interact with dietary sodium to reduce blood pressure and or intravascular volume are fully accounted for in the study design to avoid confounding the assessment of adverse events relating to hypotension or hypovolemia.

The findings are reported and interpreted in the context of other published research on dietary sodium and health outcomes.

Potential conflicts of interest are disclosed and acknowledged as a limitation in the discussion of results and are considered in funding and publication decisions.

Discussion accounts for known published research on dietary sodium and similar relevant outcomes.

Research data are maintained and are accessible for independent external review, if necessary.