So you're saying low B12 can also lead to low iron?

Yes there are several studies showing that B12 deficiency is linked to iron deficiency. And how both B12 deficiency and iron deficiency are often found together in many people. One leads to the other. And it's why I suggest fixing B12 first, then iron. Methylcobalamin produces SAMe, and high levels of SAMe are necessary to generate iron-dependent proteins and iron-dependent enzymes in the body.