Dietary Sodium Intake: Scientific Basis for Public Policy

BACKGROUND/AIMS: National and international agencies recommend a reduction in dietary sodium intake. However, some have questioned the wisdom of these policies. The goal of this report was to assess the findings and quality of studies that have examined the relationship between dietary sodium and both blood pressure and cardiovascular disease. METHODS: Literature review of the available observational studies and randomized controlled trials, including systematic reviews and meta-analyses. RESULTS: A large body of evidence from observational studies and clinical trials documents a direct relationship between dietary sodium intake and the level of blood pressure, especially in persons with a higher level of blood pressure, African-Americans, and those who are older or have comorbidity, including chronic kidney disease. A majority of the available observational reports support the presence of a direct relationship between dietary sodium intake and cardiovascular disease but the quality of the evidence according to most studies is poor. The limited information available from clinical trials is consistent with a beneficial effect of reduced sodium intake on incidence of cardiovascular disease. CONCLUSIONS: The scientific underpinning for policies to reduce the usual intake of dietary sodium is strong. In the United States and many other countries, addition of sodium during food processing has led to a very high average intake of dietary sodium, with almost everyone exceeding the recommended goals. National programs utilizing voluntary and mandatory approaches have resulted in a successful reduction in sodium intake. Even a small reduction in sodium consumption is likely to yield sizable improvement in population health.