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157: What are optimal levels of B12?

Masterjohn Q&A Files Episode 157


Question: What are optimal levels of B12?

So there's a paper called the Pathophysiology of Elevated Vitamin B12 in clinical practice that PM Schoenfeld, another Masterpass member, had given me. And this paper is very interesting because it identifies a bunch of things that high B12 can be an indicator of, not a causal factor in but an indicator of problems. And it also disputes the low end of the range. So according to this paper, we really want B12 levels above 400 picograms per milliliter, which is 295 picomoles per liter. I believe picograms per liter is what most people's lab results come in. And that's like double what most labs are using for low levels at least at the time this paper was written. I believe it's like 1400 is where their cutoff flies for potentially indicating problems.


This Q&A can also be found as part of a much longer episode, here:

078: Ask Me Anything About Nutrition, August 19, 2020

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DISCLAIMER: I have a PhD in Nutritional Sciences and my expertise is in performing and evaluating nutritional research. I am not a medical doctor and nothing herein is medical advice.

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The Masterjohn Q&A Files
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Chris Masterjohn, PhD