Can elevated B12 be a false positive and you really have a deficiency?

It is, but I understand it to be pretty rare:

“ Elevated serum B12 levels may also be associated with a functional deficiency of the vitamin. Functional deficiency has been described despite high B12 concentrations and is due to a failure of cellular uptake or intracellular processing, trafficking or utilization.”
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7550708/#:~:text=Elevated%20serum%20B12%20levels%20may,intracellular%20processing%2C%20trafficking%20or%20utilization.
Do you believe you have symptoms of B12 deficiency? My B12 was elevated and it was because I was taking Liquid IV, the electrolyte supplement. Usually there’s something you’re consuming pushing the level up.

@bettersleep68, I wonder if you are referring to this related discussion:
- Natural high levels of B12 and B6: https://connect.mayoclinic.org/discussion/natural-high-levels-of-b12-and-b6/

In addition to the information and article referenced by @emo, you might find this article helpful:
- Paradoxical Vitamin B12 Deficiency: Normal to Elevated Serum B12, With Metabolic Vitamin B12 Deficiency: https://www.iomcworld.org/articles/paradoxical-vitamin-b12-deficiency-normal-to-elevated-serum-b12-with-metabolic-vitamin-b12-deficiency-91903.html

Is your doctor concerned about vitamin B levels? What symptoms or concerns led to your question?