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How long before vitamin B tablets out of system to take blood tests

Hectorsmum2 profile image
3 Replies

My son had some blood test taken privately. Was supposed to be Active B12 and MMR folliwng borderline serum B12. The results came back middle of the range and I started him on some vitmain b tablets that include B12 to see if that helps. Anyway. I have just found out that they did total B12 test not the active B12 ordered/ They have offerred to retest or refund as it was thier mistake.

He toke the tablets for a few days. Would it be a waste of time testing active B12 now? How long should he wait after the B vits to have his blood taken again. Does anybody know?

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Hectorsmum2
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Corney23uk profile image
Corney23uk

With the Actibe B12 they usually say two weeks. Remember that many foods and drinks are fortified with B12 so take care not to have any of those during that time.

Polo22 profile image
Polo22

I can't really offer any useful advice have wondered myself about how long supplements need to be stopped to get clear unambiguous results, if only 🫣 . I 'll be watching for replies not stalking promise, as would love to know for me and daughter who are both having the usual merry go round of head numbing circular arguments with peeps who should know but have no idea. Hope you get some good advice, sure you will 🤞

Cherylclaire profile image
CherylclaireForum Support

I would think there are a lot of variables here: how much b12 in the supplement, how quickly the active becomes inactive and how quickly it is passed through system once taken.

Think this is one for the scientists: FlipperTD - any ideas ?

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