B12

[Flossiewestie2020]

I’m a little confused. I had blood tests through Blue Horizon and was told my B12 was borderline insufficient at 289; I then had blood tests through my GP a few days later and it came out at 428! I have been experiencing symptoms which I thought were related to B12 and now I don’t know which tests to trust!

[SeasideSusie Remembering]

Flossiewestie2020

What are the ranges for each test?

Have a look at the units of measurement - are they different?

Blue Horizon uses pmol/L.

My surgery uses ng/L (pg/ml is the same as ng/L).

They are not comparable, you'd need to convert one to the other.

For example,

A Blue Horizon result of 250pmol/L would be 338.75ng/L or pg/ml.

[Flossiewestie2020 in reply to SeasideSusie]

Ah, ok, thanks for this! Looks like the one from the GP is ng/L range 180-900.

[SeasideSusie Remembering in reply to Flossiewestie2020]

Flossiewestie2020

Looks like the one from the GP is ng/L range 180-900

OK, so you have 428ng/L which is the same as pg/ml and according to an extract from the book, "Could it be B12?" by Sally M. Pacholok:

"We believe that the 'normal' serum B12 threshold needs to be raised from 200 pg/ml to at least 450 pg/ml because deficiencies begin to appear in the cerebrospinal fluid below 550".

"For brain and nervous system health and prevention of disease in older adults, serum B12 levels should be maintained near or above 1000 pg/ml."

Your Blue Horizon result of 289pmol/L is the equivalent of 392pg/ml so not too far away from your GP test and gain is on the low side.

To convert B12 pmol/l to ng/L (pg/ml) you multiply the pmol/L result by 1.355 to give the equivalent in ng/L (pg/ml).

[Flossiewestie2020]

Hi, thanks for this. That’s really helpful!