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Vitamin B12 - description and reference ranges

What is it?

Vitamin B12 deficiency anaemia occurs when a lack of vitamin B12 causes the body to produce abnormally large red blood cells that cannot function properly. It is a good idea to combine the B12 vitamin test with the Full Blood Count if this is a cause for concern.

Red blood cells carry oxygen around the body via haemoglobin and anaemia is the general term for having either generally fewer red blood cells than normal or having an abnormally low amount of haemoglobin in each red blood cell.

Vitamin B12 deficiency can cause some worrying symptoms, such as extreme tiredness and lack of energy or mouth ulcers and weakness.

Reference ranges

If your indicative Vitamin B12 level is lower than the reference range for our laboratory:

Both high and low levels of vitamin B-12 may indicate an underlying problem. Vitamin B12 deficiency usually means that the body has difficulty absorbing vitamin B12 from food. It can be so due to surgery or medication, or can be genetic. It can be an indication of hyperhryroidism or anemia.

If this deficiency is caused by anemia, it is generally more difficult to rectify as it is not the delivery mechanism that is at fault but rather the inability of your body to absorb B12.

It is also entirely possible to have high or low levels of B12 and not have any health concerns.

You should discuss this result with your GP if you have concerns or symptoms.

If your indicative Vitamin B12 level is higher than the reference range for our laboratory:

Both high and low levels of vitamin B-12 may indicate an underlying problem. High levels of B-12 may increase your risk for cancer and can be a sign of liver disease, types of leukemia or diabetes, as well as kidney function problems.

It is also entirely possible to have high or low levels of B12 and not have any health concerns.

You should discuss this result with your GP if you have concerns or symptoms.

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