It is much more common to have a problem later on in life, but the most common thing is high blood pressure, which of course then increases your risk of heart disease and heart attacks, stroke, etc. This tends to be the thing that has an effect on a lot of people. There's also some connection with possible nerve issues, since it all relies on electrolyte balances to send nerve impulses.
Here is a nice link I found, but to much sodium is bad, and it hurts you more as you age.
http://funadvice.com/r/14oajl1v9o2
Well I know salt sucks up the water in ur system and causes dehydration