Welcome to NeuroTalk:

If you went GF and felt better... that is your answer.

Being gluten intolerant is associated with leaky gut....and malabsorption of nutrients. Are you still taking your B12 (on an empty stomach) and your D3? You should still be taking it.

Other nutrients may be affected by gluten intolerance ...magnesium, calcium, zinc, selenium, all the B's and other nutrients. Over time you may become low in any or all of these as well.

There are other culprits... the nightshade veggies can also create havoc. Potatoes, tomatoes, peppers of all kinds, eggplant. Potatoes especially contain the highest amounts of the alkaloid solanine, which is implicated to be cumulative in the body, so symptoms appear with age/time.

Low D can cause all sorts of tingling/paresthesias. This is because of poor calcium absorption due to the low D.

Things like this are ongoing. They don't "go away", and thus they are for life. That is your genetic inheritance.

The celiac community is now discussing the gluten intolerance issue as a separate disease entity:
http://www.ncbi.nlm.nih.gov/pubmed/23211856

There are bacteria that can cause PN. Old fish, and some from contaminated chicken, etc. Campylobacter is one organism that can cause PN...sometimes severe involvement.
Inflammation of the GI tract also can contribute to leaky gut...where things slip thru tiny openings into your blood stream to cause allergic reactions. Normally the GI wall separates you from nasty stuff you might swallow. But in leaky gut scenarios, peptides, and organisms can enter the body where they don't belong. Some people have immune systems then that over-react and inflammation starts in the intestines. In the worse case scenario Crohn's disease or colitis may develop.