Vitamin B-12 Level High While Taking Supplements

by Laurie

My fathers B-12 was low back in Seotember 2015 and his caretaker started supplementing 5000 mcg daily. The doctors never did a follow up until I requested one, which was drawn 3 days ago (1-18-16).

The result was 1862 - way over the normal range of 211 -911. In reading about the possible side effects of too much B-12, I found a side effect listed that stood apart from the rest, which had to do with increasing certain cancers... specifically Prostate Cancer, which he has!!!

My question to you is.... what dosage is a safe dosage and for how long? I do not want his B-12 to get low again because he gets depressed and he also has mild Dementia. At the same time, I don't want it to get so high that it could be exascerbating the Prostate Cancer, which at 89 years old he has decided not to treat.

Please advise.

Comments for Vitamin B-12 Level High While Taking Supplements

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Ignore the blood test.
by: Kerri Knox, RN, The Immune Queen

You cannot get an accurate blood test while on Vitamin B12 supplements. There is no risk of cancer from high B12 levels from SUPPLEMENTS. The risk comes from having high levels when you are NOT taking supplements.

This is because a high level when NOT taking supplements indicates the MTHFR Gene.

Don't worry about his high level. He was low. He needed Vitamin B12. There is no known toxicity with B12 supplements, just be sure that he's taking Methylcobalamin B12 for his neurologic health.

Vitamin B-12 Level High While Taking Supplements
by: PJ

If a person has symptoms of b12 deficiency while taking supplements, should she stop supplements before getting an MMA test? If so, how long before the test should supplements be stopped?

MMA test is worthless on supplements
by: Kerri Knox, RN, The Immune Queen

The MMA test is worthless while you are on supplements. Don't waste your time and health care dollars.

How long to wait after you are off supplements before doing an MMA test? I have no idea, but would suspect that it would be several months in order for it to be accurate.

Even then, the MMA test is not particularly accurate and can give false negatives. The BEST test is simply to take B12 and see if it makes you feel better, or resolves your symptoms.

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