Vitamin B12 deficiency

Vitamin B12 Deficiency and Pernicious Anemia

We get many enquiries from people suffering from acute or on-going symptoms of regular pins and needles in the limbs or similar unusual ‘sensations’; these are either people contacting us directly or via our health practitioner network. The most common causes are a Vitamin B12 deficiency and on occasions problems due to nerve impairment in the back or neck. In the latter case this can often be related to work, home or sports issues such as poor posture for desk workers or those undertaking heavy manual work. It can also more rarely be due to vertebral collapse, which is potentially very serious, so in all instances must be medically assessed.

Indeed one of our team recently went through such a worrying episode of ill health. The symptoms started one morning on waking with bad pins and needles in one arm; assuming it was due to sleeping on the arm to cause the sensation he wasn’t concerned.

However a few days later on waking with similar symptoms and feeling quite fatigued his concerns grew; especially when the tingling and numbness in varying severity became a constant ‘companion’ in arms and legs over the coming days. In total the sensations lasted some six weeks before going completely.

Such symptoms can set the alarm bell ringing as in the very worst case scenario it may be a precursor sign of Multiple Sclerosis (MS), diabetes or ME (chronic fatigue). However the likelihood is rare, and in such instances would generally be accompanied by other symptoms too; for example blurring of vision, problems with mobility and balance, muscle weakness and tightness and typically also for diabetes (or pre-diabetes) frequent urination and increased thirst (amongst other symptoms).

When such abnormal sensations like pins and needles persist in the limbs the most common causes (in no particular order) are alcohol abuse, malnutrition, vitamin B12 deficiency and spinal cord damage or entrapment. In all cases, including MS and diabetes, the problem is caused by nerve damage. Issues with the spinal cord may result from something as innocuous as poor posture through to trapped nerves and disc problems; carpal tunnel syndrome for example is often accompanied by tingling symptoms in the hands.

When pins and needles symptoms persist for a length of time the concern is always what nerve damage may have occurred. The Myelin sheath protects our nerves in the body and damage to the sheath if too severe or left untreated will become permanent.

Identifying the cause of these symptoms is of course the first and most important objective. Thereafter the symptoms should be treated according to aetiology and diagnosis, as recommended by your Doctor.

Vitamin B12 deficiency

We are going to focus in this article on Vitamin B12 deficiency, and touch briefly on the related nutritional ailment of ‘pernicious anemia’. The information on the NHS website (link below) states that:

“Both vitamin B12 deficiency and folate deficiency are more common in older people, affecting around 1 in 10 people above the age of 75. Vitamin B12 deficiency is rare in younger people, although those who follow a strict vegan diet may be more at risk. Pernicious anaemia, which is the most common cause of vitamin B12 deficiency, affects 1 in 10,000 people in northern Europe.”

Vegans and vegetarians are often at risk of vitamin B12 deficiency as the vitamin is mainly found in animal based foods such as meats and offal. The Vegan Society comments “Very low B12 intakes can cause anaemia and nervous system damage. Most vegans know that B12 deficiency can cause neurological complications and tingling sensations or numbness.” The link to the Society page on B12 is below and excellent and informative reading for everyone whether on dietary restrictions or not.

Vitamin B12 contributes to the normal function of the immune system and is necessary for normal nerve cell function and is involved in protein, fat and carbohydrate metabolism. Vitamin B12 helps in the utilisation of iron in the body and aids in the production of DNA and RNA, the body’s genetic material. The human body’s absorption of vitamin B12 appears to decrease with age and therefore low levels of vitamin B12 are more likely to be identified in people over 50.

Good natural food sources of the vitamin are Fish, dairy products, organ meats (especially kidney and liver), eggs, beef and pork, pickles, nuts and seeds, yoghurts, miso, sourdough bread and soy sauce, ‘Marmite’, cheese and milk.

Vitamin B12 is one of eight ‘B-Complex’ Vitamins which are necessary for the normal functioning of the nervous system and may be the single most important factor in the maintenance of the nerves. Indeed one of the key factors exacerbating B-Vitamin depletion in our body is stress. The nervous system needs a good supply of B vitamins and magnesium for its functions. During times of stress the nervous system is more active and hence needs more nutrient support. Excess alcohol intake also severely depletes the body of many nutrients and particularly B-Vitamins.

The water solubility of the B-Complex vitamins means that any excess is excreted and not stored (e.g. excreted by going to the toilet or sweating); therefore they must be continually replaced. This is a key point to make with problems relating to Vitamin B12 deficiency. Symptoms of deficiency can typically take between 3 to 5 years to manifest themselves as, uniquely among B vitamins, a supply of B12 is stored in the liver. Symptoms are generally only apparent once the reserves in the liver have become depleted. Hence at this stage someone is significantly low in B12 and this needs addressing rapidly to ensure no permanent nerve damage occurs.

Pernicious anemia

Pernicious anemia is the more common form of Vitamin B12 deficiency and more likely to occur in those over 60, women and those with a genetic predisposition. Pernicious anaemia is an autoimmune condition that affects how Vitamin B12 is absorbed into your body through your stomach. The condition affects the ‘intrinsic factor’ protein in the stomach which is needed to absorb and utilise the Vitamin. This means your body cannot absorb vitamin B12 which causes a deficiency.

Pernicious anemia also affects the absorption of another important B-Vitamin called Folic Acid (or Folate). Good Folic Acid levels are important for a range of functions, most importantly growth, and hence especially important for pregnant and breastfeeding women. Other factors that could inhibit B12 absorption are digestive disorders such as Crohn’s disease, ingestion of medication called proton pump inhibitors, which lower stomach acid, and certain other medications. Also as absorption of B12 takes place at the terminal ileum, in theory any degree of dysbiosis (bacterial imbalance in the gut) can impede uptake.

So whilst some cases of Vitamin B12 deficiency occur primarily through poor diet or excess loss due to factors such as stress or alcohol many other cases occur with pernicious anemia and other similar conditions that adversely effect the body’s ability to absorb the vitamin.

Recommended Daily Allowances

A range of health experts believe that the European recommended daily allowances (RDA’s) for B-Vitamins and particularly B12 are much too low. The same debate continues regarding RDA’s for other vitamins and minerals too, for example Vitamin D intake. Indeed the dosage of a lot of B12 supplements on the market is 500ug (per tablet) and this would be in line with many health practitioners’ recommendations as a typically suitable intake for many in the adult population.

‘Sublingual’ Vitamin B12 is becoming an increasingly popular option to supplement with. Sublingual literally means ‘beneath the tongue’ and these tablets will quickly dissolve in the mouth and rapidly allow the Vitamin B12 to be absorbed into the blood vessels and thus avoid the problems associated with digestive tract uptake.

Both Sublingual Vitamin B12 and the tablet form should ideally be in the form of ‘Methylcobalamin’. Methylcobalamin is universally bio-effective whilst Cyanocobalamin B12 supplements needs to be enzymatically converted to Methylcobalamin in the body. Some people do not break down the ‘Cyan’ element and it accumulates as a toxin. Others cannot transform Cyanocobalamin to a methylated form – so the universal solution is a) Methylcobalamin and b) in a sublingual form – this ensures even those with very low stomach acid absorb the nutrient.

When looking to supplement for folate deficiency we would recommend ‘Methylfolate’ which is emerging as a new and exciting food supplement for anyone who needs to supplement with Folate/ Folic Acid. Methylfolate (also known as 5-MTHF and L-Methylfolate) is the most stable, safe and bioeffective form of Folate. If you are supplementing with folate over the long term it is advisable to simultaneously supplement with B12, as folate can mask a b12 deficiency.

If you are concerned about Vitamins B12 and Folic Acid deficiency you should consult a doctor or qualified health practitioner. If a doctor suspects pernicious anemia they make take a blood test and in some cases where the condition is confirmed sufferers are given Vitamin B12 regularly via an injection.

And finally to our colleague whose symptoms started this article. After a thorough health appraisal it appeared very likely that he was indeed short of B12. On our recommendation he took up to 1000ug of Vitamin B12 a day. As his symptoms gradually improved and no additional symptoms had manifested we felt confident that B12 deficiency was likely to be contributing to the discomfort in his hands and legs. This seemed likely as he had also suffered a prolonged period of stress, and digestive problems. As originally mentioned the pins and needles were gone after around six weeks and he is fully fit and well again.

If you are concerned that you may be deficient in Vitamins b12 or Folic Acid please do contact your Dr in the first instance. If you have any questions on this article please contact me (Amanda) by phone or email at any time.

Amanda Williams
01684 310099


NHS: Pins and needles

NHS: Anaemia, vitamin-B12 and folate deficiency

Pernicious Anaemia Society

Vegan Society – Vitamin B12

Last updated on 15th December 2014 by


9 thoughts on “Vitamin B12 Deficiency and Pernicious Anemia

  1. Hi Amanda, which of Cytoplan’s products would you recommend for B12 deficiency in a lacto-vegetarian / vegan diet?,, and what would you recommend for children to take/ Thank you

    1. Hi Alison,

      Go for our 500ug METHYLCOBALAMIN. The same is fine for children, as the tablets are small, but in ages 4-8 go for 1 tab every 3 days.

      Email me you address and I will send you a pot to get you going –

      Best wishes


  2. Amanda, please can I point out that most B12 deficient patients would need B12 injections for the symptoms you describe (for life) and unless their deficiency was dietary they would probably still be symptomatic. Was your colleague a vegan?
    I am concerned that you state B12 is in nuts etc. There are in fact, no useful sources of B12 in any foods other than animal products the body simply doesn’t recognise these B12 analogues.

  3. I’ve just had blood tests done, and my vit B12 is high. I do suffer from tingling in feet and hands and suffer from nerve problems.

  4. I’m having the same symptoms of this article on b12 deficiency but no diagnosed by any pratictional.but by tomorrow I will.

  5. My mother is also suffering from similar signs and she has lost her ear senses(she can’t hear) anymore, what should we do please

    1. Hi Okuk – it would be best for you to contact our office directly (01684 310099) or complete one of our free health questionnaires (click here), so we can understand more details about your mother’s current health conditions in order to advise safely. I hope this helps.”

    1. Hi Kumanya – There is evidence to suggest that metformin could be related to Vitamin B12 deficiency and that the deficiency may occur less in those taking a multivitamin containing B12. In most instances it is wise to take the “B Complex” vitamins together based on their functional relationships – but to discuss your individual requirements please do contact our team on nutritional therapists at

We'd love your comments on this article
It's easy, just post your questions, comments or feedback below

Names will be displayed as entered. Your email address will not be published. Required *