I've had a salt craving problem for a long time. I can't remember exactly how long, but definitely more than five years. It was never serious enough to make me seek medical attention, but it kind of bothered me; I was worried about hypertension in the distant, nebulous future that no one likes to think about. The craving got worse after I moved to America. The whole thing made no sense at all -- the taste of salt comes from sodium, and in our sodium-saturated food environment it is inconceivable that anyone could have a deficiency of it.
Then, about a week ago, the craving virtually disappeared. Pleasantly surprised, I tried to figure out what I'd been doing differently in the week before that. With a flash of insight, it all fell into place.
Our ancestors, both primate and otherwise, got their salt from salt licks
. In addition to sodium, these also contain trace minerals -- calcium, iron, phosphorus and zinc, according to wikipedia. Instead of learning to taste these individually, and develop specific deficiency-cravings for each, evolution took a short-cut because these were usually found together in nature: we only taste sodium, and crave it in response to a deficiency of any
trace mineral. Indeed, the thing I'd been doing differently was taking multivitamins regularly, which contains ample amounts of all the above trace minerals and many more.