Vitamin B12 absorption

How do you know if your body can absorb vitamin B12? What tests are best to show if absorption is good? Where is the best place to have the tests?

20 March 2016

Vitamin B12 deficiency is a type of anaemia where the body produces abnormally large red blood cells but these cells then fail to function properly. It is otherwise known as a Folate deficiency. These red blood cells lack haemoglobin which is needed to enable oxygen uptake.

Symptoms of Vitamin B12 deficiency include extreme fatigue, lack of energy, muscle weakness, problems with mental agility, depression and possibly a sore swollen tongue or mouth ulcers. Changes to skin palour, eye sight and a pins and needles sensation can also occur.

Causes of this type of deficiency can be linked to:


  • Poor nutritional status, as a result of malabsorption of nutrients in the stomach or intestine e.g. due to known IBS/Crohn’s Disease
  • Through choice of diet e.g. vegan/vegetarian
  • Medications e.g. those used to minimise stomach acid production.
  • Other medical illnesses such as those involving the renal or hepatic systems.


Diagnosis of this deficiency can be confirmed by a means of a blood test which specifically looks at your red blood cell count. This test would look at the presence of red blood cells and how they are functioning and how much haemoglobin is present.

This test can be done at your local GP surgery or hospital in conjunction with any other blood tests to exclude any other medical concerns.

Your GP will use the symptoms you are presenting with and the results of blood tests to determine whether you are suffering from this deficiency.

Treatment of Vitamin B12 is usually achieved through maintaining a good healthy balanced diet, with the use of supplements or Vitamin B12 injections and investigation into possible causes for the deficiency.

Depending on the reason for the deficiency you may well find that a referral to a Gastroenterologist or Dietician may be required.

We would encourage you to seek an appointment with your GP to discuss any symptoms and concerns that you have and we are sure that your GP will be more than happy to test you for any deficiencies or causes for your symptoms.

Some useful reading that may also be of assistance to you can be found at:

Vitamin B12 or folate deficiency anaemia

Blood tests

Answered by the Health at Hand nurses  

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