How Much Sodium is Added to Water?

That depends on the hardness of the original water. This table shows the additional amount of sodium consumed by drinking one quart of softened water. Initial Hardness Sodium Added 1.0 grains per gallon 7.5 milligrams/quart 5.0 grains per gallon 37.5 milligrams/quart 10.0 grains per gallon 75.0 milligrams/quart 20.0 grains per gallon 150.0 milligrams/quart 40.0 grains per gallon 300.0 milligrams/quart As a comparison, one slice of white bread has 161 milligrams of sodium; 3/4 cup of canned baked beans = 1130 milligrams; 1 tablespoon of catsup = 204 milligrams; 1 medium frankfurter = 610 milligrams; and 1 cup of whole milk = 127 milligrams. Even a common Alka Seltzer tablet contains 532 milligrams of sodium. However, if you suffer from hypertension or are on a sodium restricted diet, you should consult your doctor about the proper water for drinking.