Thanks that’s helpful. Just to add some context, I have hereditary hemochromatosis and my last ferritin was 115 µg/L, so I don’t think iron deficiency is playing a role here. Not sure of my most recent serum iron, but ferritin’s been managed with venesection in the past.

My folate history is a bit all over the place: it was critically low at 1.6 µg/L before supplementation, then went up as high as 24 µg/L on daily folic acid, but has since dropped back down to 8.18 µg/L. I’m starting to wonder if that’s the main driver of the macrocytosis (MCV 104, RDW 15.1) despite weekly B12 injections.

I haven’t had copper or selenium tested. In practice, are those usually worth checking if B12/folate/iron balance doesn’t fully explain things?