Findings and Conclusions for Cardiovascular Disease, Stroke, and Mortality
General U.S. Population
Finding 1: The committee found that the results from studies linking dietary sodium intake with direct health outcomes were highly variable in methodological quality, particularly in assessing sodium intake. The range of limitations included over- or underreporting of intakes or incomplete collection of urine samples. In addition, variability in data collection methodologies limited the committee’s ability to compare results across studies.
Conclusion 1: Although the reviewed evidence on associations between sodium intake and direct health outcomes has methodological flaws and limitations, the committee concluded that, when considered collectively, it indicates a positive relationship between higher levels of sodium intake and risk of CVD. This evidence is consistent with existing evidence on blood pressure as a surrogate indicator of CVD risk.
Finding 2: The committee found that the evidence from studies on direct health outcomes was insufficient and inconsistent regarding an association between sodium intake below 2,300 mg per day and either benefit or risk of CVD outcomes (including stroke and CVD mortality) or all-cause mortality in the general U.S. population.
Conclusion 2: The committee determined that evidence from studies on direct health outcomes is inconsistent and insufficient to conclude that lowering sodium intakes below 2,300 mg per day either increases or decreases risk of CVD outcomes (including stroke and CVD mortality) or all-cause mortality in the general U.S. population.
Finding 1: The committee found that the evidence from multiple randomized controlled trials (RCTs) that were conducted by a single investigative team indicated that low sodium intake (e.g., down to 1,840 mg per day) may lead to greater risk of adverse events in congestive heart failure (CHF) patients with reduced ejection fraction and who are receiving certain aggressive therapeutic regimens. This association also is supported by one observational study where low sodium intake levels in patients with CVD and diabetes were associated with higher risk of CHF events.