[drswami]

I am wondering what to make of these B-12 blood test results. All taken this year. None of the doctors i have seen have any idea. they all think the 2nd reading was a mistake, but i figure if i was taking 20,000 per day for three weeks it could well have been correct. Since the Nov 23 test i have started on 5000 a day again, on an empty stomach.

My main interest here is that even though I was consuming 1000mcg per day for the past six months, the level has dropped. Any insight would be much appreciated.

March 17............162 pg/ml
Started talking 20,000mcgs per day. sometimes without food

April 7 ................5297pg/ml
Took 1000mcg per day with food (a different brand)

June 2.................879pg/ml
Continued taking 1000mcg per day with food

November 23........849pg/ml
Started on 5000mcg per day again.

[mrsD]

We had a poster here, and I have seen on the net a couple of times comments from a lab technician in the US that most testing places (at least here) cannot go up past 2000.

What may have happened to you is that when you started, with that 20mg daily, you flooded the serum, which then went to storage both in the liver and spinal fluid, and when that was normalized, your readings dropped. If you had depleted your liver and CNS you would have had symptoms and been in a bad way. It takes time to recover the levels in those two places.

Many informational sites say that our livers' if in good shape, can store enough B12 to last 5 yrs. This is because we evolved in an ice age where food was hard to get sometimes. Being hunter gatherers we had lean times and rich times.

[drswami]

thanks mrs D.

what do you think of the fact that the level has dropped even though i have been taking 1000mcg's per day over the last six months?

does this mean that none of it is being absorbed.

a gastroenterologist i saw said it was too late to find out why my b-12 count was initially so low, because i had already started supplementation.

is he correct?

[mrsD]

Yes, basically if you get that low there is only one reason...
failure of intrinsic factor.

Readings in the 800's are not that bad. Sometimes the real answer eludes us. Just do what you need to do. I think 5mg daily is plenty, for most people.

See what happens over 3 or so months.

[nanmiya]

Hello, no one seems to have posted here for a while, but I'd like to ask a question here as it seems to be the appropriate spot.
My Primary is going to test me for my B12 and D levels when I have my physical in January. (about 1 month from now.) I have been taking a B complex and multivitamin as well as a few other supplements for two years, and D3 since this summer, and it does not seem to relieve symptoms of peripheral neuropathy. I am wondering if the supplements can mask a b12 deficiency when I am tested? I read somewhere that Folate in the supplements can mask anemia while neuropathy progresses. Should I stop taking the supplements in the month leading up to the test? Or should I just continue and thereby know whether I am absorbing the vitamins or not?

[mrsD]

Originally Posted by nanmiya

Hello, no one seems to have posted here for a while, but I'd like to ask a question here as it seems to be the appropriate spot.
My Primary is going to test me for my B12 and D levels when I have my physical in January. (about 1 month from now.) I have been taking a B complex and multivitamin as well as a few other supplements for two years, and D3 since this summer, and it does not seem to relieve symptoms of peripheral neuropathy. I am wondering if the supplements can mask a b12 deficiency when I am tested? I read somewhere that Folate in the supplements can mask anemia while neuropathy progresses. Should I stop taking the supplements in the month leading up to the test? Or should I just continue and thereby know whether I am absorbing the vitamins or not?

Most B complexes have B12 in them. A very small amount. If you have intact intrinsic factor, you will absorb this B12. If you do not (due to autoimmune disease or genetic failure) the B12 in it will not be high enough to be passively absorbed (like other things are). In cases like this where folate is eaten (fortified foods) or in vitamins and B12 is low, there can be warning signs in the blood work. An elevated MCV may be present before anemia starts. From what I have read, one does not have to have frank anemia to be low in B12.

Some of the Bcomplex is very rapidly removed from the body thru the urine. Most people can smell this and see a greenish yellow color to show the complex was "absorbed" from the GI tract. However, B12 does not give this sign. Regular Thiamine, B2, and B6 can do this however. Being absorbed is not the same as being "utilized" by the body once absorbed. The cyano form present in most vitamins, has to be converted and methylated to active methylcobalamin before being able to work. Some people cannot methylate because they lack genetic capability to do so. This is called the MTHFR mutation, and when this is present (about 10% of people), folate and B12 cannot work for you.

So the bottom line is -- I'd stop the vitamins a week before the testing. Since they appear to not be working for you anyway, you should not experience any changes.

I think you can stop your B-complex a week before the testing.
If you are absorbing the B12 because your intrinsic factor is working, your blood levels will not change much. During testing one does not want the immediate amounts of this vitamin showing up temporarily in the blood from a supplement (or injection) to confound the results.

It is true in very low B12 patients, the folate will mask anemia.
Neurological symptoms may be due to low B12, or other triggers. Doctors who use "anemia" as a sign of low B12 miss about 80% of the cases that have neuro problems without showing this symptom. Texts that they had in school which are old, use that criterion. This paper, written in 1999 , suggests that even people with fairly normal B12 levels there can be neurological problems that require more than normal intake:
http://neurotalk.psychcentral.com/post698522-70.html

[nanmiya]

Mrs D, Thank you so much for your fast response with such clear explanations!
I appreciate your advice and will stop B12 a week ahead of the blood draw as this makes a lot of sense now. Thank you also for the link. I am going to go read it right now.