After discussing my previous post about “low sodium salt” with some folks (one of whom was my former high school chem teacher), it seems as if I was a bit too hasty in jumping to my conclusion that the product contained 33% sand. When I saw silicon dioxide (sand) listed in the ingredients list, much more prominently that it was listed in the “regular” varieties, I figured I was on to their game.
But as it turns out, I was wrong after all. The product does not contain a significant amount of filler. So back to the original question. How do you get low sodium salt? I was partially right, I suppose, in that they reduce the overall quantity of salt (not just sodium) you consume, but not by replacing it with filler as I thought. The key is in the words “per teaspoon”. The product is described on Diamond Crystal’s website:
Salt Sense® brand is 100% pure salt with 33% less sodium by volume. The result of our patented manufacturing process is a natural flake-shaped crystal that is less dense than that of common salt. These crystals dissolve faster to give you real salt taste, without leaving any metallic aftertaste. It’s simply the sensible way to enjoy real salt.
Emphasis mine. That seems to be the answer. Because their crystals are irregularly shaped, they do not pack together as well as would uniformly shaped crystals when you scoop them. Thus, in a given volume of crystals, there will be more void (empty) space than would be present if the crystals were uniformly shaped. So less mass, ie less salt. 33% less, if they’re to be believed.
So there ya go. This should be taken as a lesson to not jump to conclusions in science. Nine years and two engineering degrees later, my high school chem teacher is still busting my ass. Restores a bit of faith in the future of humanity.
And no, I will not go run three miles.
520 Chestnut 
http://gravelkraken.com/2012/08/doomed/