Vitamin B12 deficiency anaemia or folate deficiency anaemia occur when a lack of vitamin B12 or folate causes the body to produce abnormally large red blood cells that cannot function properly.
The main symptoms of vitamin B12 deficiency or folate deficiency anaemia are:
- tiredness
- lethargy (lack of energy)
Anaemia
There are several different types of anaemia, and each one has a different cause. This article focuses on anaemia that is caused by a lack of vitamin B12 or folate in the body.
This article also covers pernicious anaemia (an autoimmune condition where the body’s immune system attacks cells in the stomach), which is the most common cause of vitamin B12 deficiency.
The most common type of anaemia is iron deficiency anaemia, which occurs when the body does not contain enough iron to produce red blood cells.
See the Health A-Z topic about Iron deficiency anaemia for more information about this condition
Vitamin B12 and folate
Vitamin B12 and folate work together to help the body produce red blood cells. They also have several other important functions:
- vitamin B12 helps to keep the nervous system (brain, nerves and spinal cord) healthy
- folate is important for pregnant women because it reduces the risk of birth defects in unborn babies
Vitamin B12 is found in:
The best source of folate is green vegetables such as:
- broccoli
- Brussel sprouts
- peas
How common is vitamin B12 deficiency or folate deficiency?
Both vitamin B12 deficiency and folate deficiency are more common in older people, affecting around 1 in 10 people above the age of 75. Vitamin B12 deficiency is rare in younger people, although those who follow a strict vegan diet (a diet that only contains food from plants) may be more at risk.
Pernicious anaemia, which is the most common cause of vitamin B12 deficiency, affects 1 in 10,000 people in northern Europe.
Outlook
Vitamin B12 deficiency anaemia can be treated with vitamin B12 supplements. Vitamin B12 is usually given by injection every other day for two weeks, followed by tablets, until the deficiency is under control.
Folate deficiency anaemia can be treated with folate supplements. Folic acid tablets are used to restore folate levels, which usually need to be taken for four months.
Depending on the underlying cause of a vitamin B12 or folate deficiency, dietary improvements can prevent the condition returning, or supplements may need to be taken for life.
