A review of methods to measure dietary sodium intake.

With the rising prevalence of heart failure, it is imperative to investigate reasons for dietary sodium nonadherence and to develop evidence-based interventions to promote adherence. However, one of the biggest obstacles in studying adherence to a low sodium diet is the imprecision in measurement of dietary sodium intake. The purpose of this article is to critically review current methods used to measure dietary sodium intake. Specifically, 24-hour urine, single- and multiple-day food records, and 24-hour dietary recalls are compared and contrasted. The reliability and validity of these methods are discussed. When choosing a method to measure dietary sodium, it is important also to consider other strengths and weaknesses of each method. The "best" method to be used in research may depend not only on the above information, but also on the research question as well as characteristics of the population under study.