Study estimates 24-hour sodium intake and urinary potassium excretion in U.S. adults

What is already known?

High blood pressure is a major risk factor for heart disease and stroke. Reducing sodium intake and increasing potassium intake can lower blood pressure. Accurate measures of intake can inform programs to reduce sodium. The 24-hour urine measurement was recommended as the gold standard for assessing sodium intake because it captures all sources and does not rely on self-report. Prior studies in which adults living in the United States collected 24-hour urine were not nationally representative.

What does this article add?

The main objective of this study was to estimate mean U.S. sodium intake from 24-hour urine measurements and to provide estimates of 24-hour urinary potassium in adults ages 20 to 69.

In 2014, CDC collected 24-hour urine in a nationally representative cross-sectional survey of 827 U.S. adults ages 20 to 69. The data from this study provide a benchmark for dietary sodium intake among U.S. adults in that age range:

  • Mean 24-hour urinary sodium excretion was 3,608 milligrams (mg).
  • Mean sodium excretion was higher in men (4,205 mg) than in women (3,039 mg).
  • Mean sodium intake levels from 24-hour dietary recall data and 24-hour urinary excretion were similar.
  • Mean 24-hour potassium excretion was 2,155 mg.

What are the implications of these findings?

  • Mean sodium intake may be about 4,000 mg per day, given that the amount in urine is about 90% of what is consumed in the diet.
  • The average amount of potassium intake measured in the 24-hour urine collection was lower than current recommended levels; however, the amount of potassium in urine can vary 50% to 90% from the amount consumed.
  • These findings can inform recommendations and efforts to reduce sodium and increase potassium intake in the U.S.

Citation

Cogswell ME, Loria CM, Terry AL, Zhao L, Wang CY, Chen TC, et al. Estimated 24-hour urinary sodium and potassium excretion in US adultsExternal. JAMA 2018;319(12):1-12. doi:10.1001/jama.2018.1156.