About 4 weeks ago, having felt increasingly tired for some time, I suddenly realised I had many of the symptoms of B12 deficiency. I contacted my GP surgery and asked if I could be tested. The surgery responded that the GP wanted a face to face appointment before testing and that would be in 2 weeks time then a blood draw a week later. At that time I was not supplementing so I explained that I was afraid not to start supplementing for 3 weeks and could I have the test first. Reply was still no. Now I realise I should have had a private blood test done. So, since I was worried because some of the symptoms I have are neurological I started supplementing B12 and not surprisingly blood test results show no deficiency.
Please, can you give me suggestions for what to do next? Is there a reliable list of B12 symptoms my GP would accept? Is there a way to test for B12 deficiency now that I am supplementing? What can/should I do?
Thank you very much for reading and for any help offered.
Written by
thyr01d
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How much B12 were you taking? What were your B12 levels? If your level is still fairly low with the supplementation you may be able to persuade your GP you have B12D.
I did the same thing as you. I took 2000 mcg daily for over two months before I managed to get a blood test. It was at the start of the first covid lockdown and I was in such a state I couldn't wait to see the GP. I couldn't stand up without help, couldn't talk properly and had no control over my bladder.
The GP said I didn't have B12D but I managed to convince him as my reading was still fairly low ( just over 300 ). With the amount of B12 I was taking it should have been much higher.
Thank you for your reply, I will look to see how much B12 I am taking and enter it, however I have not been as ill as you obviously were and although I can't remember my B12 reading I don't think it was low.
UK guidance on B12 deficiency suggests that people who are symptomatic should be treated even if their serum B12 level is within normal range.
Summary of BSH Cobalamin and Folate Guideline includes the statement
"In the presence of discordance between the test result and strong clinical features of deficiency, treatment should not be delayed to avoid neurological impairment"
It's vital to get adequate treatment. Inadequate treatment may lead to an increased risk of permanent neurological damage. In severe cases, spinal cord may be affected.
If you're symptomatic and your GP refuses to treat you, may be worth discussing the affect B12 deficiency can have on the spinal cord with GP as this may make them take more notice.
PAS article about SACD, sub acute combined degeneration of the spinal cord
I urge UK forum members to find out what's in the local B12 deficiency guidelines used by their ICB (Integrated Care Board) in England or Health Board in Scotland/Wales.
If you can't find them online or by searching posts on this forum then best bet is to submit a FOI (Freedom of Information) request to ICB or Health Board asking which b12 deficiency guidelines are used locally and for a link to or copy of them.
Some local B12 deficiency guidelines in UK are unhelpful. See blog post below.
Thank you Sleepybunny, so much information. At the moment I am struggling more with cognition than with movement so will have to work through your post over several days. Please, could you point out where I should start? What should I address first? Thank you
Hi thyr01d good to see you here! At the moment I can't add much more beyond what sleepybunny has posted. Please read and ask away. B12 seems simple but is far from, as you can see.
Hi Jade, it's so good to see you here, you are making me feel supported and hopeful, like a friend 🙂. I have posted my relevant test results and info about supplementation and just remembered I left some out so will add. How are you today?
Here are my latest test results (all had alongside the comment:"please interpret result against reference range, which may have changed, very carefully)" and supplementation. Any suggestions of what else might be causing symptoms if not B12 deficiency would be very welcome. I am already treated for underactive thyroid.
Vitamin B complex containing 2.5 ug (100% RDA) for 3 months
Vitamin B12 1,000 mcg (40,000% NRV) - for 3 weeks prior to testing, between 1 and 3 tablets per day sublingually which I know is overdosing and likely to put other B vitamins out of balance.
Serum vitamin B12 level 573 ng/L [197.0 - 771.0]; Please note change in analytical method from 25/10/2022. Normal B12 levels do NOT exclude pernicious anaemia. If there is strong clinical suspicion of pernicious anaemia with a normal B12 level, please discuss with Consultant Haematologist.
Serum ferritin level 42 ug/L [13.0 - 150.0];
Serum folate level 19.4 ug/L [3.9 - 26.8];
Haemoglobin A1c level - IFCC standardised 39 mmol/mol [20.0 - 41.0]; NICE GUIDANCE FOR TYPE 2 DIABETES (2002). Target HbA1c of 48-59 mmoL/moL should be set for individual, balancing risk of vascular disease against risk of hypoglycaemia and personal circumstances.
Full blood count
Haemoglobin concentration 124 g/L [120.0 - 160.0]
Red blood cell count 4.12 *10^12/L [2.81 - 6.49]
Haematocrit 0.380 L/L [0.36 - 0.46]
Mean cell volume 92 fL [80.0 - 100.0]
Mean cell haemoglobin level 30.1 pg [27.0 - 32.2]
Mean cell haemoglobin concentration 329 g/L [300.0 - 350.0]
Red blood cell distribution width 13.6 % [8.0 - 14.0]
The only thing that stands out is low ferritin. I would ask GP for a full iron panel which includes: serum iron, % saturation, TIBC. One can have low ferritin but normal iron, so you need the full panel before starting any iron supplements. Iron is toxic at high levels. But low iron/ferritin can also cause fatigue and similar symptoms. I think some of the thyroiduk rec'd labs also have this test if you want to do it privately. GP was not concerned I assume?
B12 is raised as one might expect.
Folate is good. How long had you been taking the b complex & how much folate does it have? Supplementing folate can mask the red blood cell abnormalities often used to diagnose b12d. But don't worry too much about that now - up to 20-30% of people b12d develop neurological symptoms but never any RBC abnormalities.
Your RBCs look fine though RDW at 13.6% is starting to trend high. That could potentially be a mix of low iron and B12D, the first can causes smaller rbcs, the latter causes larger. On average rbcs then look ok but the RDW will be higher because you have more variation in the size of the rbcs.
One option is to work on iron while stopping b12, then get retested in a few months and see how far B12 has fallen in that time.
Do you have any b12 results from any time in the past?
As for your question to sleepybunny, i would start out with reading the symptoms sites. See how many apply. Let us know if you have any , especially the neurological signs.
Then maybe read the testing links. Two tests they can do now are intrinsic factor (IF) and gastric parietal cell antibodies. Unfortunately they can come back negative (saying not PA) half the time in people who truly have PA. But still worth testing. A positive IF antibody test is diagnostic of PA regardless of b12 levels.
After that, you can browse on the PAS, B12DInfo, and the dutch b12stichting english pages to learn more about PA. And then come back & ask about anything that's unclear
Might be worth asking GP if this is something that needs looking into.
Low platelet levels can be associated with folate deficiency and B12 deficiency. There can be other reasons as well.
I was pleased to see that there is a message in your results that says "Normal B12 levels do NOT exclude pernicious anaemia. " Might be worth asking the GP about this.
If you think it's possible you might have PA then worth joining and talking to PAS (Pernicious Anaemia Society).
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.
I had a good day, thanks! Went to the beach. Perfect weather for it! 
Is B12 196 normal?
Low haemoglobin
I wrote a letter, and this is what I got back. 
Tests needed for daughter already supplementing with injectable b12
Please advise me
