I merged your apology post into this thread, so it is all in one place and easy to find until you get familiar with the site...

If you click the NeuroTalk logo it will bring up a listing of all of our forum topics, you may find something interesting there -
http://neurotalk.psychcentral.com/index.php

--that bypass operation should be investigated.

There have been anecdotal reports of neuropathy due to nutrient deficiency/malabsoprtion following gastric bypass. B12 deficiency has often been a culprit. as the body needs intrinsic factor in the gastric tract (and available surface area) to break this out of food and be absorbed properly.

See:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1483244/

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3237207/

http://www.neurology.org/content/63/8/1462.abstract

A conscientious surgeon should alert a gastric bypass patient to the possibility of such malabsorption post surgery and about the likely need to supplement, probably for life.