I would look at nutrients in general on this forum. Lots of good information, and you may need to cover a lot of bases, since you have a broader absorption problem.

I would start with B complex, at least 1000 mcg B12 (methylcobalamin form best), and a good multivitamin/mineral. Then I would read about L-carnitine and various other things that can help the brain.

Happy reading.

rose