Does salt cause thirst? It's really not all that certain

Conventional wisdom contends that the consumption of salt makes us thirsty and therefore leads to increased drinking to restore the balance of minerals in the body. Prof. Leshem commented that because many of us consume beverages with high caloric content -- alcoholic or sugary drinks -- there is evidence that increased consumption of salty foods leads to an overall increase in the consumption of calories and contributing to obesity.

However, according to Prof. Leshem, despite our gut feeling that salt increases drinking, this relationship has not been studied in conditions simulating salt-rich foods such as savory appetizers. Therefore, in the present study involving 58 student participants, Prof. Leshem sought to investigate the effect of salt in solid foods on drinking. Participants were scheduled to come to the lab every few days after not having eaten or drunk anything except water, and not having smoked, for two hours. On the days they came, they were asked to taste nuts -- one time sugary candied nuts, another time salted nuts, and yet a third time nuts with no additives. They rated their level of thirst and, during a couple of hours in which they responded to various questionnaires, they got bottles of water. Each subject could drink as much water as he or she wanted.

The main finding was that the level of reported thirst and the actual quantity of water that the subjects drank after eating salty nuts were not different than following consumption of candied nuts or nuts without added flavors. To more deeply examine a possible correlation, the researchers selected the 10 male and 10 female students who had consumed the largest quantities of salt (an average of 4.4 grams and 3.7 grams respectively) and sought to determine whether within this subgroup there was a connection between thirst and drinking, but here too no such correlation was found. This means that even those subjects who consumed larger quantities of salt did not drink more .

Besides the scientific implications regarding the balance of salts and fluids in our bodies and diet, Prof. Leshem suggested, with a pinch of salt, that "based on the findings, tavern owners can reduce the amount of salt in their bar snacks without compromising their drink sales or customer health.