Why would you want to increase sodium?
Did you know, too much sodium in your body causes high blood pressure or heart attack?
Ex: there are over 1,000 mg. in some ready made soup from an Asian store. There are so many products hidden with high mg. of sodium, and people take them everyday.
Eat dried fish they're high in sodium.
My parents both very petite, had high blood pressure, and they're always adding salt to their meals because they're used to their foods being salty, and they can't figure it out why it's high and they take all kinds of herbal foods to keep it lowered down, but it's in their system and as long as they inventory up on table salt they couldn't lower it down.
Just so you know
they do contain sodium, but in such small quantities, and usually as a compound or a by product. you will not be able to increase your body sodium levels significantly by using say sleeping pills before you over dose and die.
the best way to increase sodium levels in your body will be by eating salty food