I am still trying to figure out a cause to my idiopathic foot neuropathy, which came on fast in May 2019. The word "idiopathic" does not mean there is no cause, it just means no one knows what it is.
Blood sugar is not high (A1C within normal range), do not drink alcohol, B12 is low but with supplements and shots is fine, I have a lower back issue, but two MRIs do not see anything that could be the cause. Mine is numbness only, feet only, and I am told it is mild, though it borders on pain at times. I walk twice a day for an hour each time. Walking helps it to some extent. I take R Lipoic Acid, Magnesuium (glycinate), Acetyl-l-Carnitine, N-acetyl cysteine, BenfoMax (thiamine) -- so far they don't seem to do anything.
One possible smoking gun is weight, and possibly carbohydrates.
Earlier this year I put on 10 pounds relatively quickly (205 > 215) and I definitely noticed my feet were worse. I am now on a mission to get down to 185 which is a more or less ideal weight for me. Will report back if it works.
Foot neuropathy is worst when I first get out of bed. Also, sometimes I am very achy getting out of bed, including lower back, and sometimes I am not. I think there is a correlation between how much I eat late that day -- the more I eat the worse I feel the next morning. Fasting (skip dinner) is the main way I am trying to lose weight. It works great, but keep something like celery sticks around for munching at night as need.