The Truth About B12

I often come across lots of queries about B12, and this is often met with widely varying advice, some of it not entirely accurate. Recently, I even saw somebody suggest that vegans should buy B12 for injection online, and invest in some insulin needles. I can firmly advise that you should not be buying injections of B12, nor administering it yourself, but here is what you do need to know.

B12 is used by the body in the production of red blood cells. It is only found in animal derived foods, so all vegans should be taking a daily supplement. There are no plant based foods that contain B12. The recommended daily intake of B12 is small, being only 1-2μg/day. The vegan vitamin B complex that I take (from a well-known health food shop) contains 25μg per tablet, and the recommended dose is 2 tablets per day – a plentiful supply of B12.

Doctor’s guidelines for treating B12 deficiency are not always followed in the same way. This leads to mixed messages about how it should be managed, and many people with low B12 levels may find they are treated in different ways. Firstly, I should mention that GPs shouldn’t really be checking B12 levels unless their patient has signs or symptoms of deficiency. These include:

  • Peripheral neuropathy
    • a nerve disorder usually affecting the feet, experienced as loss of feeling, tingling or numbness
  • Sore, red, broken skin at the corners of the mouth (rarely caused by B12 deficiency)
  • Sore, swollen, red tongue (again, a rare symptom of B12 deficiency)
  • Dementia/serious memory problems
  •  Optic neuritis
    • An eye condition of loss of vision and eye pain

Your GP may also check your B12 levels if you have symptoms of anaemia (I’ll cover this in another blog), and a full blood count confirms that you are anaemic with red blood cells that are bigger than they should be. So, as you can see, B12 levels aren’t checked routinely.

So what happens if you do have low B12 levels?

If you have any of the symptoms above, or your full blood count is abnormal, then your GP will probably start you on injections. These are given into a large muscle, not into the skin like insulin, and this is why it can’t be self administered with insulin needles (apart from the fact that injecting anything into your body without medical supervision is extremely unsafe). But anybody who is found to have a low B12 level, but remains well, can safely take an oral version, and this is being encouraged more and more. It is worth considering that if you are well, even if you have low B12 levels, you will not be given injections.

As a final note, I would just like to mention something about our responsibility to preserve our NHS. As you probably know, I work as a GP, and I can honestly say that I have never been more worried about the future of our healthcare system. It is teetering on the edge of non-existence, and it is all of our responsibility to do what we can to save it. As a vegan, I know that I have a very healthy lifestyle, but I need to keep myself well by taking necessary supplements. As a GP, I know that veganism is not an illness. Please keep yourself well by taking the supplements you need, seek medical attention if you are unwell, but don’t expect unnecessary treatment that the NHS can not afford. If you are certain that you want your B12 levels to be checked, but are not showing signs of deficiency, please consider one of the many laboratories who offer blood tests for a small charge.

Thanks for reading,

The Vegan Doctor



4 thoughts on “The Truth About B12”

  1. I’ve taken B12 supplements from time to time, but I eat fortified foods pretty much every day. Do you think that’s enough to cover my intake or do I need to religiously take a pill a day? I’ve been vegan on and off for 15+ years and haven’t had any symptoms of deficiency I’m aware of.


    1. Hi, if you can be sure that the b12 content of your food, and hence what you’re actually taking, equals the recommended daily dose, then I don’t see a problem. Sometimes it’s difficult to work out, so taking a supplement with a known quantity of b12 gives you that peace of mind too.

      Liked by 1 person

  2. I have been taking B12 tablets to be on the safe side. I also take a vegan omega 3 supplement and would be interested in any information you have about ALA, EPA and DHA. You may already have covered this topic?
    About the NHS. My parents became NHS doctors in 1948, the first year and worked their socks off thereafter. Not all of it was necessary. I knew it was time for father to retire when one morning I overheard a snippet of telephone conversation with the wife of a disruptive patient who had sabotaged his nights sleep. “Well, I can’t examine him with his head down the toilet,” he said helpfully. (Time to retire old man, I thought).
    Veganism, if we do it right, is a great way to support the NHS and do our duty to keep healthy for as long as possible. Diabetes, atherosclerosis, stroke, heart attack, dementia and many other conditions are own goals, cared for by the NHS, but in the States the patient pays, through their insurance company, if they are lucky, or maybe not at all. There is a vested interest in America for the insurance industries to maintain high tech medical approach and ignore what can be achieved by healthy living. But with the NHS there is an opportunity to fix the diet and save billions of tax payers money on treating patients with avoidable illness. Never mind Brexit, stub out that cigarette and try eating and drinking sensibly.
    We all owe it to the NHS and ourselves to make lifestyle changes before some HMG in the future says ‘This is too expensive…’ and calls in the insurance companies instead. Then we really will be stuffed.


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