dence on the impact of dietary patterns low in sodium and/or low in saturated fat and high in potassium (e.g., DASH [Dietary Approaches to Stop Hypertension] and Mediterranean diets) on risk of CVD, stroke, and mortality and concluded that plant-based, lower-sodium dietary patterns had a beneficial impact on CVD risk. However, the dietary patterns included in the evidence review included dietary modifications other than sodium reduction that have been shown to have a cumulative impact on risk of CVD and related diseases. These include increased potassium, reduced intake of saturated and trans fats, and increased intake of dietary fiber. Based on their review of the evidence, the DGAC (HHS and USDA, 2010b) concluded that reduced risk of CVD, stroke, and disease-related mortality was associated with total dietary modification. Nevertheless, decreasing sodium intake has a potential role in reducing risk of CVD, stroke, and mortality, and this was the primary focus of the committee’s review.
As noted in Chapter 3, blood pressure is used as a surrogate indicator for CVD, stroke, and mortality risk, especially among individuals who are already at risk of disease. The committee’s review of the strength of new evidence for dietary sodium and its effects on blood pressure concurred with previously established evidence (see Chapter 3). This evidence that high sodium intakes can indirectly mediate risk of adverse health outcomes underpinned the committee’s assessment of evidence on associations between sodium intake and direct health outcomes. Taking the evidence for blood pressure effects into consideration as background, the committee focused its review on new evidence on sodium intake and direct health outcomes, particularly evidence from intervention studies where available.
Each outcome is discussed in turn, presenting the available data organized by population group, and within each group organized alphabetically by the last name of the first author. Each study is described by its population, size, and characteristics; study design, purpose, and length; sodium intake measure and method; range of intake, reference intake, and adjustments; outcome measure, confounders, and adjustments; and direction and significance of effect. For each major outcome of CVD, CHF, and CKD, the committee provides a summary table evaluating each study using as criteria the generalizability of the study population to U.S. populations and the appropriateness of the methodology used to support the findings and conclusions.
Finally, a summary of findings and conclusions is given on each major outcome for general populations and for population subgroups of interest as described in the statement of task, specifically those with hypertension or