5 signs you may be low in Vitamin B12

5 signs you may be low in Vitamin B12

Vitamin B12 - also known as 'The Energy Vitamin' - plays a vital role in a variety of reactions around our body. It is involved in the formation of red blood cells, DNA, and the normal function of the nervous system. We're three times more likely to be deficient in Vitamin B12 after the age of 60, and women and those on plant-based diets of all ages are most likely to be affected by a deficiency. 

A deficiency in Vitamin B12 can result in anaemia and nerve damage, and here we explain potential signs of Vitamin B12 deficiency. 

5 Signs of low Vitamin B12

1. Feeling weak and fatigued

Vitamin B12 is vital for making healthy red blood cells which carry oxygen around your body. Low levels of Vitamin B12 can reduce the oxygen being transported to your body’s cells, making you feel tired and weak. 

You may enjoy 'How to beat chronic fatigue'.

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2. Feeling dizzy and out of breath

Anaemia caused by Vitamin B12 deficiency can result in feeling dizzy and out of breath. This happens as the red blood cells are not able to transport enough oxygen to your body’s cells.

3. Mouth ulcers and sore tongue

A sore, red or swollen tongue can be an early sign of Vitamin B12 deficiency.2 The inflammation of the tongue makes it look smooth and can change the way you speak and eat. This condition is known as ‘Glossitis’. Mouth ulcers may also occur with Vitamin B12 deficiency.

Ulcers and burning mouth and tongue is also a symptom of menopause, learn more about the surprising and more unusual symptoms of menopause.

4. Pale or yellow tinge to the skin and white of the eyes

Vitamin B12 deficiency can lead to a type of anaemia called ‘mega-loblastic anaemia’, in which the red blood cells are large and fragile. 

The fragile red blood cells break down causing an excess of 'bilirubin', a slightly brown or red coloured substance that is produced by the liver when old red blood cells are broken down. This is what gives the skin and whites of the eyes a yellow tinge.

Learn more in 'Vitamins to support vision and eye health'.

5. Pins and needles

Vitamin B12 is needed to produce 'myelin', a substance that forms a protective layer around your nerves. Low Vitamin B12 can lead to damage to this protective layer and cause nerves to stop functioning properly.  Pain, numbness or a prickling sensation in your hands and feet, like pins and needles, may occur when your Vitamin B12 levels are low.

If a Vitamin B12 deficiency is left untreated, damage to the nervous system could affect your balance and coordination, which can impact the way you walk and move.

Want to know if you're low in Vitamin B12?

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Who's at risk of Vitamin B12 deficiency?

Deficiency of Vitamin B12 usually occurs due to problems with how your body absorbs it. Vitamin B12 has to be combined with a protein in your stomach called ‘intrinsic factor’ before your body can absorb it. Pernicious (harmful) anaemia can occur when you have a lack of ‘intrinsic factor’ and is a condition most commonly found among middle-aged and older adults. 

Discover the 'Best protein sources on a plant-based diet'.

Vitamin B12 deficiency due to inadequate dietary intake is less common, however it is much more common among plant-based and vegan diets because B12 primarily comes from animal foods. If your diet is vegan or plant-based and you’re not eating animal foods, or foods fortified with Vitamin B12, it is likely you won't be getting enough Vitamin B12.  

Opt for foods fortified with Vitamin B12 including yeast extract, such as Marmite or yeast flakes, some plant milk alternatives, soya yoghurts and breakfast cereals. Also consider a Vitamin B12 supplement

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If your diet contains some animal products (e.g. meat, fish, dairy, eggs), then it is likely your requirement for Vitamin B12 will be met.

Vegan Vitamin B12 is among the most common supplements to take on a vegan diet, either on its own or within a Vegan Daily Multi-Vitamin.

View our range of vegan vitamins & supplements.

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1. NHS (2020) Symptoms Vitamin B12 or folate deficiency anaemia. Available: https://www.nhs.uk/conditions/vitamin-b12-or-folate-deficiency-anaemia/symptoms/

2. Graells et al (2009) Glossitis with linear lesions: an early sign of vitamin B12 deficiency. Available: https://doi.org/10.1016/j.jaad.2008.09.011

3. Dusol & Schiff (1975) Clinical approach to jaundice. Available: 1080/00325481.1975.11713948

4. Miles et al (2015) Is there an association of vitamin B12 status with neurological function in older people? A systematic review. Available: 1017/S0007114515002226

5. The Vegan Society (2020) Sources of Vitamin B12. Available: https://www.vegansociety.com/resources/nutrition-and-health/nutrients/vitamin-b12