Possible B12 deficiency, unhelpful GP, worth testing?

Hi Staticline,

The symptoms you describe could well be B12 deficiency.  You are not anaemic, but you could still be B12 deficient - this is my own pattern - and you will still have symptoms.  You have been supporting your nutrient levels with multivitamins, and presumably have a healthy lifestyle too, and this could be disguising a problem.  You simply need to bring this to the attention of your physician when discussing your blood test results.  B12 deficiency can be caused by a number of things (including an auto-immune condition and some cancers) so it is well worth getting a B12 test.  If you are deficient, then you absolutely MUST investigate the cause.  Treatment with B12 injections may resolve the symptoms, but not the cause.  Repeated testing, with or without treatment, is a good way to establish whether your condition is a "blip" or more chronic, and how you are responding.  If you have the auto-immune condition (they can test you specifically for this) you won't find it easy to absorb B12 from your diet or supplements, and injections will be needed to raise your levels.  The results of long-term B12 deficiency are many and serious, so don't be fobbed off.  Insist on testing. Some medicines deplete B12 too, so check out the side effects of any medication you are on, and ask for injections to counteract them.  Good luck.

You have many symptoms.  Might be an idea to go to a different GP.  Your doctor should be investigating your symptoms or at least referring you to a neurologist.  Have you had your thyroid checked?  Ask for b12 test and thyroid.  You can ask for a second opinion.  Hope you get to the cause of it soon. Take care x

Thank you both so much for getting back. I have never had my b12 levels checked. When I was a teenager for a few years I had spells of fainting and dizziness on standing - I think my thyroid was checked at that time, I don't know what the result was but I was informed it was borderline and given my young age not worth treating. As far as I'm aware it's never been repeated or followed up. I guess I will have to bite the bullet and face up to my GP, as I am becoming increasingly concerned about my walking and lack of coordination. Thank you for giving me that confidence.

Hi Staticline, well it looks like the first thing you should do is sack your doctor. A simple search on the web or in PubMed will show you several studies that show that vitamin B12 deficiency is associated with tachycardia. Your doctor should be up on this work. You can cite the PubMed reference http://www.ncbi.nlm.nih.gov/pubmed/24366986

The reason why B12 causes this is because your basal heart beat rate and in fact breathing rate is controlled by adrenalin. Methylcobalamin (one of the two active forms of B12) is involved in the synthesis of adrenalin and in fact the highest concentration of methylcobalamin in the body is the adrenal glands. Now the other thing is that this type of tachycardia is associated with adolescents (you said you were young) as they have an increased demand for vitamin B12 as they lay down more myelin sheaths. Apart from the symptoms themselves, one would be worried that you are not properly laying down myelin on your nerves. You say that you have been taking 2.5 mcg B12 daily for years, this suggests that you know that you are not getting B12 in your diet. FYI the suggested level is 6 mcg/day from several studies in Europe. Now this has to be spread over 3 meals as you can't absorb 6 mcg in "one hit" as the uptake system cannot transport that amount at any one time. This of course assumes that your normal uptake system is not compromised and that you are not taking various drugs that affect uptake. Your other symptoms also are common to B12 deficiency, and are often seen without anemia. If you do go see your doctor again, I would take him the reference and try to be polite about it, well at least it might help some other poor unfortunate person. Good luck.