During my 16-17 months of this illness, I had lost the lunulas (light-colored 'moons') on my fingernails. I did not really notice this until they came back recently. Their reappearance exactly coincides with the start of taking b12+ methylation supplements. Apparently the lack of lunulas is a sign of b12 deficiency. So I'd say the b12 is back - and let's hope it's working its magic on all of my neurological problems, too. I'll take it as a good sign.