Perspective:

The following are 10 points to remember from the Institute of Medicine’s report on sodium intake:

1. The Committee on the Consequences of Sodium Reduction in Populations 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.

2. 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 cardiovascular disease (CVD).

3. This evidence is consistent with existing evidence on blood pressure as a surrogate indicator of CVD risk.

4. The committee found that the evidence from studies on direct health outcomes was insufficient and inconsistent regarding an association between sodium intake below 2300 mg/day and either benefit or risk of CVD outcomes (including stroke and CVD mortality) or all-cause mortality in the general US population.

5. The committee concluded that the available evidence suggests that low sodium intakes may lead to higher risk of adverse events in mid- to late-stage congestive heart failure (CHF) patients with reduced ejection fraction, and who are receiving aggressive therapeutic regimens.

6. The committee concluded that, with the exception of the CHF patients described above, the current body of evidence addressing the association between low sodium intake and health outcomes in the population subgroups considered is limited.

7. The committee further concluded that, while the current literature provides some evidence for adverse health effects of low sodium intake among individuals with diabetes, chronic kidney disease, or pre-existing CVD, the evidence on both benefit and harm is not strong enough to indicate that these subgroups should be treated differently from the general US population. Thus, the committee concluded that the evidence on direct health outcomes does not support recommendations to lower sodium intake within these subgroups to or even below 1500 mg/day.

8. The committee found that the available evidence on associations between sodium intake and direct health outcomes is consistent with population-based efforts to lower excessive dietary sodium intakes, but it is not consistent with previous efforts that encourage lowering of dietary sodium in the general population to 1500 mg/day.

9. Additional observational and randomized controlled trials are indicated to assess approaches using dietary sodium intake levels corresponding to levels in current guidelines (i.e., 1500-2300 mg/day) when examining associations between sodium intake and health outcomes.

10. In addition to randomized clinical trial research, mechanistic studies are needed to examine potential physiologic changes associated with lowering sodium intake and adverse health outcomes.