High sodium, low potassium diet associated with higher risk of death

A diet high in sodium and low in potassium raises the risk of death from any cause by 50% and doubles the risk of death from heart attack, according to a new study from the Centers for Disease Control and Prevention (CDC), Emory University, and Harvard University.

Researchers analyzed data from the Third National Health and Nutrition Examination Survey (NHANES) Linked Mortality File (1988-2006)-a study of a nationally representative sample of 12,267 adults-to assess estimated usual sodium and potassium intake and sodium-potassium ratio in relation to all-cause mortality and death from cardiovascular disease.

Higher sodium intake was associated with greater all-cause mortality (hazard ratio [HR], 1.20); higher potassium intake was associated with lower mortality (HR, 0.80). Subjects in the highest quartile for sodium-potassium, compared with the lowest quartile, had an adjusted HR of 1.46 for all-cause mortality, 1.46 for death from cardiovascular disease, and 2.15 for death from ischemic heart disease. The findings didn’t differ significantly by sex, race and ethnicity, body mass index, hypertension status, education level, or physical activity. The study was published in Archives of Internal Medicine (2011;171[13]:1183-1191].

“The study’s findings are particularly troubling because US adults consume an average of 3,300 milligrams of sodium per day, more than twice the recommended limit for most Americans,” says co-author Elena Kuklina, MD, PhD. She notes that the findings provide “further evidence to support current public health recommendations to reduce sodium levels in processed foods, given that nearly 80% of people’s sodium intake comes from packaged and restaurant foods.”

Kuklina notes that “increasing potassium intake may have additional health benefits.” Potassium is present naturally in many fresh foods, such as yogurt, milk, and fruits and vegetables.

The United States Department of Agriculture Center for Nutrition Policy and Promotion’s 2010 Dietary Guidelines for Americans recommend a sodium intake of no more than 1,500 mg per day for people 51 years of age and older, African Americans, and people with hypertension, diabetes, or chronic kidney disease and a daily intake of no more than 2,300 mg for everyone else. The guidelines also recommend consuming 4,700 mg of potassium per day.