I was just feeding my addiction to health articles last night and read this one.
It's actually about men being deficient in many key nutrients, but when you read down to the section about B12 there was some very interesting information... something I did not know at all.
Metformin inhibits absorption of B12. No one ever told me that.
Also, I had previously read somewhere that many women that experience recurrent pregnancy loss are deficient in B12 (try googling it of you want to know more).
So while I was TTC I took an additional B12 (just in case) with about 800% the DV (B12 does not have significant overdose risks). I ran out the other week and stopped because my new prenantal has a higher amount of B12 than my old, but now, after reading this information, I'm going out to buy some more B12 today.
I just wanted to share since so many of you all are metformin takers too.