to total sodium intake (Mattes and Donnelly, 1991). Because these data showed such practices to be a relatively small contributor to overall sodium intake, behavior change messages generally have not targeted home salt use. Use of table salt continues to be a relatively minor contributor to overall sodium intake. Current data suggest that table salt contributes 4.9 percent to total sodium intake (see Chapter 5). Data from the National Health and Nutrition Examination Survey (NHANES) III (1988–1994) suggested that 50 to 72 percent of adults “never” or “rarely” added salt to table foods (Loria et al., 2001). Similar results were seen in the 2005–2006 NHANES in which 68 percent of all persons reported never or rarely adding salt at the table (Moshfegh, 2009). Survey respondents were also asked how often ordinary or seasoned salt is used in cooking or preparing foods in the home; response options and the percentage of respondents choosing these responses in 2005–2006 included “never/rarely” (24 percent), “occasionally” (37 percent), and “very often” (40 percent). This information is applied to algorithms for recipes and sodium absorbed in cooking (Moshfegh, 2009).
Many of the major initiatives of the past 40 years have called for a reduction in the sodium content of marketed foods through direct appeals to food processors and through the availability of labeling provisions to provide additional incentives for the development of lower-sodium foods. This section reviews available information on the following:
sodium content of foods;
relative contributions of different sources to total sodium intake;
use of sodium-related label claims and advertising; and
availability of lower-sodium food products.
Marketed foods influence the sodium intake of consumers in two primary ways: through their sodium content and through the amounts consumed. This section focuses on the sodium content of foods from various food channels—that is, the various sources of foods available to consumers. The following section focuses on how changes in portion sizes and energy intake have affected the relative contribution of different food channels to total sodium intake.
One way to directly compare the sodium content of foods from different sources without the confounding effect of variations in consumer use is to compare their sodium intake densities, defined as the number of milligrams of sodium per 1,000 calories. As shown in Panel A of Figure 2-4,