Vitamin B12 or folate deficiency anaemia
Vitamin B12 or B9 (commonly called folate) deficiency anaemia occurs when a lack of vitamin B12 or folate causes the body to produce abnormally large red blood cells that cannot function properly.
Red blood cells carry oxygen around the body using a substance called haemoglobin.
Anaemia is the general term for having either fewer red blood cells than normal or having an abnormally low amount of haemoglobin in each red blood cell.
There are several different types of anaemia, and each one has a different cause. For example, a common form of anaemia is iron deficiency anaemia, which occurs when the body does not contain enough iron.
Vitamin B12 and folate perform several important functions in the body, including keeping the nervous system healthy.
A deficiency in either of these vitamins can cause a wide range of problems, including extreme tiredness, a lack of energy, pins and needles (paraesthesia), a sore and red tongue, muscle weakness, depression and/or problems with memory, understanding and judgement.
Some of these problems can also occur if you have a deficiency in vitamin B12 or folate but do not have anaemia.
When to see your GP
You should see your GP if you think you may have a vitamin B12 or folate deficiency. These conditions can often be diagnosed based on your symptoms and the results of a blood test.
It’s important for vitamin B12 or folate deficiency anaemia to be diagnosed and treated as soon as possible because, although many of the symptoms will improve with treatment, some problems caused by the condition can be irreversible.