Pernicious Anaemia Society
14,606 members10,407 posts

B12 too low?

B12 too low?

Hi everyone,

I am member over on Thryoid UK and recently had a private full blood screen done. Would someone be able to take a look at my levels for b12, ferritin, folate etc and see if you think I should a) ask the doctor (good luck to me) to test/treat b12 or b) supplement B12 myself?

I have some symptoms which fall under b12 shortage but many of them also go hand in hand with my Hashimotos hypothyroid diagnosis. The ones which I though were more likely to be indicative of b12 problems are waking up at night with numb/tingling arms and cramps in my legs. The memory problems, slow cognition, word retrieval issues and general brain fog I put down to thyroid but maybe they're also related to b12? I also have digestion/constipation problems and go through periods of clumsiness both in walking and handling objects. I have also experienced muscle fatigue and breathlessness which I again attributed to my thyroid.I have bad eyesight to start with but some days even with glasses or contacts it doesn't seem as clear as others.

There's a bunch of other stuff which may be thyroid related or both. I guess based on the basics I've given and my blood screen I wondered what people might think about asking to be tested/treated and self-supplementing.

Thanks in advance

3 Replies

Hi Harrisan I think that if a NHS B12 test result came out the same you would be hard pushed to persuade a "Normal" doctor to prescribe treatment, but if you list your neurological symptoms you might be able to get a course of injections in line with the NICE guidelines on treatment of B12 Deficiency.

Click on the link, then on "Scenario Management".

However there is also your low Vitamin D some symptoms of which are similar to those of low B12.

I am not a medically trained person but there are others on here who will be able to give you good advice


Personally I would advise sorting out the obvious issues - thyroid and Vit D - both of which could explain the majority of the symptoms you have - and then come back to B12 if sorting those out doesn't resolve the problems.

Serum B12 is a difficult test to evaluate and needs a lot of contextual information. Whilst it will miss 25% of people who are B12 deficient about 5% of people are actually okay with levels off the bottom of the normal range.

There are some test that could clarify - MMA and homocysteine - but as above I'd rule out thyroid and Vit D first before looking at more testing.


Thanks guys. I'm about to start a bunch of supplements to try to sort the vit d and absorption and conversion of my thyroid hormone. As per your advice I'll hold off supplementing b12. Particularly as, if I have this right, any supplementing could mask a problem in blood tests if I optimise everything else and symptoms persist and I think again about b12.


You may also like...