Vitamin B12 deficiency can occur if a person lacks the vitamin. B12 is important in the production of red blood cells, and a lack of the vitamin means a lack of red blood cells. The red blood cells which are made can also be abnormally large with a short lifespan. If the body doesn’t get enough red blood cells, tissues and organs become deprived of oxygen and the symptoms of vitamin B12 deficiency are triggered.
One symptom that could signal the condition is a fast heart rate.
Experts say this is because the heart may start to beat faster to make up for the reduced number of red blood cells in the body.
This is the body’s response to ensure enough oxygen is being circulated throughout the body.
Atrial fibrillation is the name given to a fast heart rate.
The NHS explains: “Your heart may feel like it’s pounding, fluttering or beating irregularly, often for just a few seconds or minutes. You may also feel these sensations in your throat or neck.”
While heart palpitations may appear alarming, in most cases they’re harmless.
But if you do experience them, see your GP, who can rule out if it is a vitamin B12 deficiency causing it or another condition.
Other common triggers of heart palpitations include strenuous exercise, not getting enough sleep, drinking caffeine, alcohol and smoking.
Other symptoms of vitamin B12 deficiency Bupa notes are:
- Feeling very tired
- Breathlessness even after a little exercise
- A reduced appetite
- A sore mouth and tongue
The health organisation adds: “If you have vitamin B12-deficiency anaemia, you may also look pale or jaundiced (have a yellowy tinge to your skin and the whites of your eyes).
“As well as the symptoms of anaemia, vitamin B12-deficiency may cause symptoms related to your nerves. This is called vitamin B12 neuropathy. It may affect your movement and sensation, especially in your legs, cause numbness or pins and needles and decrease your sensitivity to touch, vibration or pain. It can also cause confusion, depression, poor concentration and forgetfulness.
“These symptoms aren’t always due to vitamin B12-deficiency anaemia, but if you have them see your GP.”
How to avoid vitamin B12 deficiency
Adults aged 19 to 64 require around 1.5 micrograms (mg) a day of vitamin B12, and you should be able to get this through your diet.
Certain foods contain vitamin B12, and Harvard Health Publishing, part of Harvard Medical School, lists the best dietary sources of the vitamin.
Here are five:
- Clams – three ounces contains 84mcg of B12
- Liver – three ounces contains 70.7mcg of B12
- Fortified cereal – one cup contains 6mcg of B12
- Beef – three ounces contains 1.5mcg of B12
- Egg – one large egg contains 0.6mcg of B12
- Nonfat plain greek yoghurt – six ounces contains 1.3mcg of B12
Who is most at risk of vitamin B12 deficiency?
The NHS Trusts explains who’s most at risk of vitamin B12 deficiency.
It says: “Vegans and vegetarians consuming limited dairy produce have a higher risk of developing vitamin B12 deficiency due to limited dietary intakes.
“The elderly population and people taking metformin for a long time can also be at increased risk of vitamin B12 deficiency due to vitamin B12 not being absorbed properly in the body.”
If you consume very little vitamin B12 foods you may be advised to take a vitamin B12 supplement or to have vitamin B12 injections.
This may be the case for pregnant or breast feeding women and vegan or vegetarians.
If you take vitamin B12 supplements, the Department of Health advises you don’t take too much as this could be harmful.
Taking 2mg or less a day of vitamin B12 in supplements is unlikely to cause any harm.