Average Sodium Intake Tied to Good Cardiovascular Outcomes

Americans’ average daily sodium intake may be associated with better health outcomes than recommended intake levels.

Most Americans’ average daily sodium intake is associated with better health outcomes than intake levels currently recommended by the CDC and major health departments, according to a new study. Many in the scientific community now view the latter intake levels as excessively and unrealistically low, it was suggested.

Researchers at Copenhagen University Hospital and Bispebjerg University Hospital in Copenhagen, Denmark, and Albert Einstein College of Medicine in New York investigated the incidence of all-cause mortality (ACM) and cardiovascular disease events (CVDEs) in populations exposed to dietary intakes of low sodium (less than 115 mmol), usual sodium (low usual sodium, 115 to 165 mmol; high usual sodium, 166 to 215 mmol), and high sodium (more than 215 mmol). They integrated relationship between individual measures of dietary sodium intake vs outcome in 23 cohort studies and 2 follow-up studies of randomized controlled trials measured as hazard ratios in meta-analyses.

The risks of ACM and CVDEs were decreased in usual sodium vs low sodium intake and increased in high sodium vs usual sodium intake. In population-representative samples adjusted for multiple confounders, the hazard ratio for ACM was consistently decreased in usual sodium vs low sodium intake but not increased in high sodium vs usual sodium intake. Within the usual sodium intake range, the number of events was stable.

The authors said that they identified a specific range of sodium intake (2645 to 4945 mg) associated with the most favorable health outcomes within which variation in sodium intake is not associated with variation in mortality and that this optimal range of intake is consistent with the current dietary intake of most of the world’s population. They concluded that their data are consistent with the hypothesis that a U shape best describes the relationship of sodium intake to health outcomes.

The study was first published online on March 20, 2014, in the American Journal of Hypertension.