a diet with a 30–50 percent overall reduction in sodium content for 2 to 3 months, volunteers gradually developed a preference for foods with lower salt levels. In other words, they acclimated to the lower-salt diet. In a study with many more subjects, Elmer (1988) reported very similar results, as shown in Figure 3-5.

This shift in preference may also be moved in the other direction: when people were placed on a higher-salt diet, they shifted preference upward to like more salt in their foods (Bertino et al., 1986). A number of lines of evidence suggest that these shifts are due to the actual sensory experience with salt rather than some sort of physiological regulatory process (Leshem, 2009).

Most of the research on the sensory effects of lowering sodium intake was conducted more than 20 years ago, and many important questions were never fully explored. For example, it is not known whether it is necessary to reduce total sodium intake to obtain sensory accommodation or whether it would occur if salt were reduced in a single product category, such as soup or bread. That is, would the consumer begin to prefer lower-sodium soup or bread if his or her overall sodium intake was not reduced at the same time? Also, would judicious consumption of very salty food items (e.g., olives, anchovies, certain cheeses, processed meats) in the context of an overall lower-salt diet inhibit these sensory changes? Furthermore, it is also not known how long such sensory changes persist or how resistant they

FIGURE 3-5 Shifting of salt taste preference in response to a lower-salt diet. Change in salt content of the diet indicated by the change in urinary sodium excretion.

SOURCE: Elmer, 1988.