Hi hope you could advise me. When I have my bloods done I usually leave taking my iron. B12 and vitamin d supplements etc for about 7 days before my bloods are due to be done. I wondered if I'm doing the rite thing ? I'm sure I seen the info on here you should leave it a few days ? I asked my GP the other day and she told me to take everything as usual without leaving it a few days before having bloods to get a proper reading ?
Getting bloods done at the GP : Hi hope you could... - Thyroid UK
Getting bloods done at the GP
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I always leave 7 days without taking any of my vitamins, minerals and other non-thyroid-related supplements before testing.
For thyroid testing I follow the usual routine recommended on the forum.
Can I just ask for what reason is best to stop taking vitamin and minerals etc 7 days before blood tests ? This has what I've done up until now for the past 18 months but just thought I'd ask the GP . Not sure what she meant by you don't get a proper reading if I stop taking it a few days
Some minerals e.g. iron are recommended to be stopped before testing. For biotin, the higher the dose the sooner it must be stopped.
I stop for 7 days and always have done if I'm in control of the timing, just so that I don't have to worry about timing and supplements in the lead up to a test. I think if I stick to the same simple method it makes my life easier and my supplementation consistent from one test to the next.
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You only need stop biotin and iron 5-7 days before test
Don’t take vitamin supplements on morning of test
If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 5-7 days before ALL BLOOD TESTS , as biotin can falsely affect test results
endo.confex.com/endo/2016en...
endocrinenews.endocrine.org...
In week before blood test, when you stop vitamin B complex, you might want to consider taking a separate folate supplement (eg Jarrow methyl folate 400mcg) and continue separate B12
i was advised to just stop taking biotin a week before and B12 two weeks before. I still take all my other supplements.