Is there a B12 maximum reading?

Just wondered after seeing some people’s B12 results in the 1000’s following SI. Is there an upper limit where this reading tops out or is no longer within a readable range?

[fbirder]

Yes, all assays will have a level that is the maximum amount they can detect.

In the past my B12 was described as >5999 ng/L. Nowadays is is always >2000 pmol/L.

Obviously they changed the assay type about 4 years ago, and the new one uses different units and has a lower top limit.

[Hidden in reply to fbirder]

That’s very interesting. Thank you.