I was a big fan of canned soup. I kept it stocked in the pantry, but one day I started making my own soups and stocks. The difference in the taste and the price was so well worth never buying canned soup again. I started reading the ingredients on the label and notice the large amount of salt in that little can. I do not add salt to my soups, well sometimes a pinch. I do mean a pinch. I'm not a fan of salt. Here is some information on canned soups.
As is also the case with canned veggies, you are entering a sodium minefield. Half a cup of Campbell's® Chicken Noodle Soup has about 37% of the recommended daily allowance, and who eats half a cup? I would still be hungry after the whole can. I would be really thirsty afterwards.
Read that label carefully. They hide chemicals in that can. Most companies make low-sodium versions, if you must. It's still best to make your own soups. You can have complete control of what is in it. It taste so much better.