But doesn't this same principle apply to everything you eat? Too much vitamin A, too much sugar, too many preservatives, too much caffeine, etc... Some things are detrimental to the body, and are not food, some things are food, but are only detrimental at large quantities. (what isn't?)
But, your argument seems like a evasion of the truth, salt is actually food. (unless you want to argue that salt is not food, then your argument would not really apply in the same way)
If you are going to claim "too much salt" = "salt is bad", "because science", then don't you have to argue how bad water is as well (in the same manner), because the renal system also gets rid of excess water too...
http://www.nbcnews.com/id/16614865/ns/us_news-life/t/woman-d...