Vitamin B complex before blood tests

[Hopeful129]

I know that you should stop any b vitamin supplements for 3-7 days before a thyroid test due to the biotin but does this apply to other blood tests. GP wants me to do some blood tests next week for iron etc and wondering if I should stop the b complex before. TIA

[SeasideSusie Remembering]

Biotin in any supplement should be stopped for a few days before any blood test.

If you are having an iron test then this should be after a 12 hour fast so to avoid goinv without food during the day it's best to book an early appointment

Common fasting blood tests

Examples of blood tests that may require you to fast include:

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an iron blood test (used to diagnose conditions such as iron deficiency anaemia) – you may be asked to fast for 12 hours before the test

nhs.uk/common-health-questi...