Biobehavior of the human love of salt.

We are beginning to understand why humans ingest so much salt. Here we address three issues: The first is whether our salt appetite is similar to that in animals, which we understand well. Our analysis suggests that this is doubtful, because of important differences between human and animal love of salt. The second issue then becomes how our predilection for salt is determined, for which we have a partial description, resting on development, conditioning, habit, and dietary culture. The last issue is the source of individual variation in salt avidity. We have partial answers to that too in the effects of perinatal sodium loss, sodium loss teaching us to seek salt, and gender. Other possibilities are suggested. From animal sodium appetite we humans may retain the lifelong enhancement of salt intake due to perinatal sodium loss, and a predisposition to learn the benefits of salt when in dire need. Nevertheless, human salt intake does not fit the biological model of a regulated sodium appetite. Indeed this archetypal 'wisdom of the body' fails us in all that has to do with behavioral regulation of this most basic need.