"Probably the number one question arising during a discussion of water softening is that of the "sodium" issue.
It is greatly misunderstood due to all the bad press about too much salt (sodium) in the average American's diet today. Various studies contradict one another on the actual health impact of sodium in the diet. We must have sodium to live, but how much is enough; how much is too much? We will not attempt to answer those questions. However, we can put the topic into perspective by showing where the sodium in one's life comes from daily.
The standard sodium ion exchange (softening) process uses sodium (salt) to exchange the hardness ions (calcium & magnesium). Therefore, when you remove the hardness ions, they are replaced with sodium ions. The amount of sodium produced in the softening process is quite small and should not present any health problems for a healthy person. As a matter of fact, the U.S. drinking water regulations have dropped sodium as a regulated component of water. However, if a person has a question about whether or not they should consume water softened by the sodium ion exchange process, they should consult with their own health professional.
The basic information below should put soft water sodium into perspective for you relative to sodium in foods. For example, if you drank 3 quarts of water that was 10 grains hard before softening, you would only take in 223 milligrams of sodium or about 4.3% of the average daily intake of sodium attribubale to the water. This would be less than the amount of sodium contained in two slices of white bread."