Salt cravings may be the origin of all drug addictions
All humans crave salt once in a while. The desire is hardwired into an ancient part of our brains, the hypothalamus, because we need it to keep our bodies working properly. Now it looks like some of the more addictive drugs out there could be co-opting this neurological system - which means our desire for salt is what underlies our cravings for everything from heroin to coffee.
New research has shown that cocaine and opiates may hijack the same brain connections that serve to make us crave salt. The scientists discovered this when mice with blocked addiction-related pathways no longer had the sodium cravings that normal mice did.
What this also hints at is why addiction is so hard to fight: its mechanisms are baked very deeply into our brain so that we can survive. The same craving mechanism that reminds cows to lick salt rocks also keeps addicts returning for another hit.
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