Pernicious Anaemia Society
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Is B12 196 normal?

Hi everyone, I'm just after a bit of advice please.

About 6 weeks ago I went to my GP because I had tingling in my toes on my left foot, was tired all the time, getting headaches, feeling unsteady on my feet, being a bit more clumsy than usual, feeling groggy. My GP did some blood tests and it came back with very low Vit D and slightly low B12. I looked up the symptoms for B12 deficiency and it seemed quiet a good match for what I was experiencing.

My GP did another B12 test and an intrinsic factor antibody test 2 weeks later. The antibody test came back as normal and this time she said the B12 was normal at 196. She then said there was nothing wrong with me but suggested I take Vit D and B12 supplements to see if I felt any better but basically that was it.

I have since spoken to a private GP, as I have insurance, and he also thought that B12 of 196 was normal. But he has referred me to a neurologist for the other symptoms. I just wanted to know if this does sound normal for B12, do my symptoms sound like B12 deficiency, should I go back to my GP if the neurologist says everything is fine or is there nothing wrong and I'm just connecting things that are unconnected?

I should say that I'm not a veggie and eat plenty of meat, cheese, milk etc so my dietary B12 should be ok. My Dad has regular B12 injections but he is in his 80's and he doesn't know why except his levels were low. I am 49. I haven't taken any B12 supplements yet but have started D, with no effect.

It's all a bit confusing and some days I feel ok.

Any help or advice would be greatly appreciated.



10 Replies

what was the range and units. There are two units used to measure serum B12.

Being normal range is a long way from meaning it is okay for you as normal range is a statistical average of where people are okay. Using serum B12 normal range as a single measure will result in missing 25% of people who are B12 deficient. 5% can also be okay at levels below the normal range, ie its a blunt tool and the limitations of the tests need to be recognised if you are going to get a proper diagnosis.


Thanks for the reply. I don't know about the units or the range used. I am thinking I should asked for a copy of the results to get more info.

1 like

Hi Mike

Not only does the latest BMJ research summary below state there is no reliable test, but the Dutch links on the r/h side of the forum state this too. The neurological symptoms you've already described mean it's highly likely that PA/B12 is the cause, especially as it could be in the family.

GP should be able to access full document (behind a pay wall) as the document, as well as BCSH and NICE guidelines, give details of the importance of urgent treatment with injections for neurological symptoms. :

"Misconceptions about a B12 deficiency

The serum B12 test is still widely used as the test to confirm or rule out a vitamin B12 deficiency. However, a normal blood value cannot rule out a B12 deficiency, as has often been shown in scientific medical literature. Serum B12 can be false normal or even false high, while a deficiency is present.

"A value above the reference value does not automatically rule out a deficiency and a (slightly) lower value does not automatically mean a B12 deficiency, although a B12 value beneath 150 pmol/L has a specificity of 95% or more. There is a large grey area wherein a deficiency is possible, despite a normal serum B12 value.

By using serum B12 alone, many patients are being missed. Because a B12 deficiency can lead to permanent neurological damage, one should never rely on serum-B12 alone (unless obviously low) and always test at least MMA when a deficiency is suspected. Especially when neurological and/or neuropsychiatric symptoms are present, as they can become permanent without timely treatment.

We advise to combine serum B12 or Active B12 with MMA when a deficiency is suspected for increased accuracy. The problem however is that many physicians do not know these tests (MMA, homocysteine, Ative B12) or do not know how to interpret them. And if they know them, the are considered too expensive to do. Of course the cost of years of visiting doctors, sometimes with very expensive other tests, and years of medication, are much higher.

As there is no ‘golden’ test, patients with clear neurological symptoms, and no other obvious cause for those problems, should be treated with B12 injections. When clinical improvement occurs the treatment should be continued. There are numerous stories of patients who have benefited from B12 treatment, despite normal blood results."


Best wishes for better treatment.


Your right about the grey area. Lots of people feel tired and draggish who fall in the grey area category and could be considered deficient


Thanks very much for all the info, much appreciated.


Here in the USA, the labs add a caveat to the results for the Dr. to use is the diagnosis. The caveat says that neurological damage occurs in 10 % of the population when the results are below 400 pg/ml (same as ng/L).

That said, being at the low end is not good. Stress and worry use up lots of B12 so it may depend upon what else is going on in your life.

Start a logbook of all your symptoms and try to assess the severity of each one on a daily basis. This way you have a baseline to work from when discussing with your GP or specialist.

Give them a hard copy print out and ask for it to be included in your record. This way you provide the evidence that they need to justify starting you on or increasing the frequency of B12 injection.

The numbness in your toes can be just the first indication of myelin sheath erosion by homocysteine due to low B12.

Worry and anxiety along with tiredness and lethargy are psychological symptoms that arise from nerve damage in the brain. Try to measure and assess them as well. You own scoring system (say 1-5) works fine.

Once you start on supplements or injection, any further blood testing is only going to mislead the GP. Continue monitoring by your symptoms and logbook and have a frank discussion of this plan with your GP and don’t let them fob you off. Treat them like a partner and give them the evidence they need to stop the nerve damage at an earky stage.

Thr logbook will eventually also help monitor progress in the nerve repair. This occurs over months and years.

Also it helps in the case where your nerve damage causes short-term memory loss and brain fog. Try to assess these as if they are symptoms as well.


Thanks very much. The log book is a good idea, I shall give that a go. You are right I have been worrying about it so that's not helping. I don't have a particularly stressful life though.


Age 50 is the magic year that my body started falling apart and i was diagnosed with a B12 deficiency in the UK. I’ve been getting injections for 10 years now.

I’ve used the logbook method to get more frequent injections in both the UK and also after moving to the USA.

I now self inject 1ml cyano weekly and monitor myself and have annual checkups with my GP as he has to give me the prescription for the B12.


Thanks for the reply. I will try using a log book.


Hi. I just saw my general medicine doctor two days ago. I live in the US. I asked him what normal ranges are for B-12 as I kept reading conflicting reports on the internet. He said, at least the ranges for the hospital I go to, 180 or above is optimal, 145-180 is a grey area, and 145 or less is deficient. I was there to discuss my own case because I'm severely deficient, 119.3. I've read online that many people feel tired, draggish and out of breath if they fall in the grey area, even though its not technically considered to be in the deficient category. Maybe your iron is low. Try asking your doctor to run a complete blood count test, thyroid or diabetes test maybe. But it could easily be a B12 issue too...


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