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Advice for sister: low B12, high MCV

Advice for sister: low B12, high MCV


I am writing on behalf of my sister for some advice. She was diagnosed with autoimmune hypothyroidism a couple of years ago and has mostly been feeling well. However, in the last few months she has been feeling very tired, her hair has been falling out, she can't lose weight, etc. She had some bloods done and what I think are the most significant results are below. She also had a thyroid function test, but it was only TSH (result was 0.08, range 0.2-2.0); no fT4).

What leaps out at me is that she is actually deficient in Vitamin D, folate and B12 (as evidenced by a just-below range reading and over range MCV).

Her GP proposes to treat the folate deficiency alone and observe the B12 levels; they propose to do nothing about the vitamin D deficiency, although this is something my sister has suffered from on a regular basis.

We are going on holiday together to France shortly and I have said that I am happy to pay for her to have some private bloods done while we're there as it's very easy and pretty cheap. What should I consider asking for? I thought fT4, gastric parietal cell antibodies, intrinsic factor antibodies.

I note also that her ferritin could be better, although depressingly classed as normal. I will be recommending to her that she self-supplements; what is a good choice for not much money?

I seem to recall reading that treatment of a folate deficiency shouldn't begin if there's a B12 deficiency in the offing as well. Is that right?

Any advice very gratefully received; she's really not well at the moment.

2 Replies


If your sister has symptoms of B12 deficiency in b12deficiency.info/signs-an... she should go to healthunlocked.com/pasoc for advice.

VitD 71 is not deficient. It is mildly below replete and if your sister can get sun on her face and arms for a couple of hours a week she shouldn't need to supplement before October. If not 2,500iu D3 should be sufficient. She should take vitamin D 4 hours away from Levothyroxine.

Ferrous Fumarate 210mg should be sufficient to raise ferritin. She should take it with 1,000mg vitamin C to aid absorption and minimise constipation. Iron should also be taken 4 hours away from Levothyroxine.

This link will explain the high and low evaluations in her full blood count labtestsonline.org/understa...


After taking b12 and b complex vitamins for 5 months for retested and my mcv went down to 92.2 from 103.2


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