Low B12 mystery

[BigLittleRedOne]

A couple of months ago I had blood test to check hormone levels (periods had gone funny and I wondered if I was peri-menopausal).

Hormone levels all normal, as was everything else, liver, iron, folate etc. But they discovered my B12 was low and I had enlarged red blood cells (a sign of low b12 apparently)

I'm not veggie or vegan and eat plenty of meat, fish, eggs, dairy.

Had another test for intrinsic factor and parietal cell antibodies and those came back negative - so the conclusion is I don't have pernicious anaemia.

I've been taking sublingual B12 tablets at quite a high dose and these seem to have raised my levels up to normal.

BUT the doctor doesn't know why my B12 got so low in the first place, and I would like to know if I will be taking these supplements forever.

Has anyone been in a similar position?

The Intrinsic Factor test is only about 40–60% accurate, and 90% of people with pernicious anaemia test positive for anti parietal cells. So these tests cannot rule PA out. It even says this in the lab report on my blood results.

If your B12 is below range despite you eating a decent diet containing enough B12 then that proves you are not absorbing B12 from your stomach. Regular B12 injections are the treatment for this, as oral B12 replacement goes via the stomach so is also unlikely to be absorbed properly. Oral B12 may well raise your blood serum levels of B12, but this B12 may not be doing you any good if you're not absorbing properly.

Check out the B12 deficiency treatment guidelines for where you live as they all vary slightly. Also worth checking out NICE guidelines.

Hope this helps :)

Do you drink? I know alcohol can lower stored B vitamins levels.

The absorption of B12 is a tricky process. Have you taken antacid medication or reflux medication for a while, or have you been given metformin for diabetes? If you have low transit, it will also affect absorption.

I have malabsorption and have vitB12 deficiency - have nothing else wrong with me, just appears to be one of those things

You can eat a perfectly normal diet and have this if your stomach doesn't absorb properly

The fact that the sublingual supplement works might point to your stomach being the issue