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Gerald M Webb's avatar

Do you recommend checking a serum B12 or some other measure? What is an optimal level?

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Mark McDonald, M.D.'s avatar

Yes! Every laboratory uses difference reference intervals. For example, Labcorp's is 232-1245 units per ml. Unlike omega3 or vitamin D levels, where higher is nearly always better, simply preventing vitamin B12 deficiency appears to be adequate in removing that specific risk factor for depression and dementia. Another piece of useful info--if you don't want to see your doctor to get your lab, you can create your own order and pay cash (at a discounted rate) through Direct Labs or Grassroots Labs, and then go to Quest, get your blood drawn, and have the results sent directly to you. A vitamin B lab only costs around $30.

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Dave B3's avatar

What dosage do you recommend? Thanks.

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Mark McDonald, M.D.'s avatar

Check out any one of my shared plans that includes vitamin B12. I included two in this article (https://us.fullscript.com/plans/markmcdonaldmd-dementia). Designs for Health makes an excellent one. It's important to take vitamin B12 with other co-factors for proper absorption and bioavailability. Pure B12 will simply flow right through you.

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Megan Dowling's avatar

I used to take injectable methylcobalamin from Compounding Pharmacies. I can barely find it anymore. Hmm.

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Mark McDonald, M.D.'s avatar

Not at all suspicious!

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