No idea, see I kept taking the Ca, Mg, Zn, K and B complex through my longer fasts. Nov 6th 6 days into a fast I had cramps all over, my eyelids had cramps. I ate and ate myself out of ketosis and still didn't help. The cramps took 5-6 days to go away. Since then I was eating vitamins. However I have also heard mainly on here that we don't need to take vitamins. So I dunno. Just do as your body tells you.
Thanks.
Srinath.