I’ve gone looking through previous blood tests following a post this morning about b12. I found my results from a few years ago with a result of 75 pmol/l with a range of 25-165 for active B12. It was noted to be within the normal range and there was no result for total b12.
Does anyone know if active b12 should be considered in the same way as total b12 I.e. you want to be higher up the range? I can only find information about optimal results for total b12.
I’m getting a test from Medichecks again on Tuesday and and just trying to do some research beforehand.
Thanks
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Sparklyjenson
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The difference between Total B12 and Active B12 is that the Total B12 test measures B12 both bound to proteins and unbound (free/active) and doesn't differentiate, and the Active B12 test measures just free/active B12. It is said that the Active B12 is the better test.
Active B12 below 70 suggests testing for B12 deficiency according to Viapath at St Thomas' Hospital:
Reference range:>70. *Between 25-70 referred for MMA
So when your level was tested and the result was 75 then it was not suggestive of B12 deficiency but it was rather low. If you'd posted that result on the forum at the time then comment would have been along the lines of "75 is on the lowish side and only just above the level where testing for B12 is suggested and we generally suggest here that Active B12 is over 100".
Susie. There appears to be some uncertainty re replete, active B12 levels (no surprise?). Are you familiar with such uncertainty?
For info/example, see link below from Biolab which indicates >50pmol/l is replete, requiring no further action for 4 months. Since it's unusual for a test lab not to at least propose further testing eg MMA, my dad (61pmol/l) is broadly following that "guidance" despite his test lab Medichecks suggesting an MMA test. But he may take B complex intermittently too.
That article is really interesting userotc. Thank you for posting. It just goes to show what a complex journey these little nutrients take before they get absorbed, and how the conditions need to be just right. I’m not surprised it’s easy to get out of kilter.
There appears to be some uncertainty re replete, active B12 levels (no surprise?).
The Biolab link says
Interpretation of 'Active' Vitamin B12 results using the Guy's and St.Thomas' Nutristasis Unit laboratory algorithm
Patients are defined as deficient if the 'Active' vitamin B12 concentration is < 25 pmol/L.
The status of patients with 'Active' vitamin B12 concentrations between 25 and 50 pmol/L (the intermediate range) requires further investigation and this is best carried out using the serum methylmalonic acid (MMA) assay ..................
Patients with 'Active' vitamin B12 levels above 50 pmol/L are replete and require no further investigation for at least 4 months. ............
Yet the same lab (as in the link to Viapath at St Thomas's given above) says
Reference range:>70. *Between 25-70 referred for MMA
So as always there is contradiction so who do you believe? Is Biolab's "interpretation" just that because it doesn't seem to be what Nutristasis are saying and Nutristasis and Viapath are one and the same.
Indeed there is contradiction. With dad sitting right in the middle of 50-70, it's understandable that he's uncertain.
He actually emailed Biolab about the discrepancy between their advice and Medichecks'. The reply was a bit confusing but basically passed the responsibility to his "practitioner" (which he doesn't have except for me!). Since it's the 1st time his B12 has been tested, we don't know if it's increased to 61 or decreased after a year or so of ACV. So I support his approach going forward.
My active b12 came back at 65 pmol and 2 gps didn’t feel they could order an mma so I decided to pay for it myself and an iFAB test. Had the test yesterday - I figure at least I’ll have tried the tests available. I hate doing nothing. It’ll either help to establish a deficiency or I’ll still be unsure - at least I won’t be any worse off. Diamondgirl, what are you going to do about your result?
Hi, grateful to know what your MMA test is when received please. Can I ask was it a home test kit you ordered? My Active B12 was 54 so low end and started supplement
I’ll let you know when I get the results. I did the Medichecks pernicious anaemia test. They post a box to you and you can do finger pricks at home or take the box to a medical centre where a nurse draws blood into a vial. Then you post it. I went to a medical centre because I am terrible at the finger prick tests.
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