I never thought that salt could play a part in PN. I quit both drinking alcohol and using salt in 2006 in response to my diagnosis of high blood pressure.
But, I did not become aware of my PN until 2011.

My PN of course is "idiopathic", largely just numbness with an occasional nerve zap.

Nothing seems to either help or make the PN flare, have taken B-12 in the past to where it actually showed increased levels in lab results(about 429->912).

I still take magnesium supplements, don't really see any dramatic effect, but magnesium is essential in different ways especially in support of the nervous system.