Well, I'm no expert on salt - but as a Neti pot user I can instantly tell when I'm using grocery store salt. And, coincidentally, I worked for several years at

Well, I'm no expert on salt - but as a Neti pot user I can instantly tell when I'm using grocery store salt. And, coincidentally, I worked for several years at the shore beside salt collection fields. We all used to joke that we hoped the salt we bought wasn't from those fields - since the water was known to be very polluted (and fishing was often prohibited.) So I can't take seriously any claim that grocery store salt is the same as any given sea salt. And there are plenty of studies showing significant differences. And, at this point, the only studies I've seen about grocery store salt just tout their purity of NaCl (which, again, is not historically what salt was), and claim that the only significant consideration about salt is the things I don't care about (typically their definition of "purity").