I read another, older thread here where it was essentially stated you can't be allergic to salt. I don't know that I'm precisely allergic to it, but there's no doubt I'm extremely sensitive to it.
When I eat salty foods, it creates blisters/hives inside my mouth and throat. It took me a while to figure out what was causing the symptoms because it was always there in some form or another, though when I had sunflower seeds I had a bad enough reaction to go to the dentist, thinking I was dealing with some kind of gum disease.
But what really cinched it for me was that I'm allergic to most shampoos and couldn't for the life of me figure out what the problem ingredient was. I compared labels right and left, thinking it was probably some minor ingredient. But as it turned out, it was sodium. As in, SODIUM laurel sulfate or SODIUM laureth sulfite, which are the primary ingredients in most shampoos. Anything that includes sodium in the ingredients, I don't dare touch it. I go with something that eliminates sodium-based ingredients, the allergy symptoms evaporate.
For meals, I've switched to No Salt.
Given the fact that I have reactions both to salty foods and to non-food sodium-based products, I have to assume my body doesn't tolerate salt.