Other approaches can be used to describe the sodium content of the food supply beyond examining the main contributors of sodium to the diet on the bases of food category and types of eating establishments. However, as a general matter, the food supply as a whole has not been systematically tracked or monitored through surveys designed for this purpose. Alternatively, the sodium content of the food supply can be described using salt disappearance data (which can also be used to derive gross estimates of sodium intake). So-called “market basket” studies, such as the survey conducted by the Food and Drug Administration (FDA), could also be useful, although currently it is designed primarily for other purposes. The national databases related to food composition—which include sodium content and are maintained by USDA—cannot themselves characterize the sodium content of the food supply, but are instead a key component of the process of estimating sodium intake based on dietary recalls from a nationally representative sample of the U.S. population. However, selective comparisons of changes in food composition over time within these databases could provide some useful trend data on changes in sodium in the food supply. The only available study of this type did not include information on sodium (Ahuja et al., 2006).

Monitoring intake from disappearance data allows for a reasonably accurate estimate of time trend patterns because common methods of collecting and accounting for use have remained similar over time. Salt disap-