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Anaemia, vitamin B12 and folate deficiency

Anaemia is a condition that occurs when there is a reduced number of red blood cells or concentration of haemoglobin.
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Overview

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There are several different types of anaemia, and each one has a different cause. The most common form of the condition is iron-deficiency anaemia. This is where your body lacks enough iron to keep your red blood cells functioning properly. Other forms of anaemia can be caused by a lack of vitamin B12 or folate in your body.

This article concentrates on vitamin-B12-and-folate-deficiency anaemia.

Vitamin B12 and folate

Vitamin B12 not only helps your body to produce red blood cells, it also helps keep your nervous system healthy. Folate works with vitamin B12 to produce red blood cells, and it is also important for pregnant women, as it helps the baby to grow and develop.

Vitamin B12 is present in meat, eggs and dairy products, but it can also be found in some fortified cereals and soy products. The best source of folate is green vegetables, such as broccoli, Brussel sprouts, asparagus and peas, and also chickpeas and brown rice.

A vitamin B12 deficiency is rare in younger people, and is most common in people who are over 75 years of age. Folate deficiency is also most common in people over 75 years of age. People following a strict vegan diet tend to be more at risk of developing a vitamin B12 deficiency.

About the blood

Blood contains a fluid called plasma, which includes three different types of cells:

  • White blood cells are part of the body’s immune system and defend it against infection.
  • Red blood cells carry oxygen around the body in a substance called haemoglobin.
  • Platelets help the blood to clot.

Red blood cells are produced in the bone marrow. Vast quantities (millions) of new cells are produced each day to replace old cells that break down. Nutrients from food, such as iron, and vitamins such as B12 and folate (also known as folic acid), help ensure that your bone marrow remains healthy and is able to produce a constant supply of red blood cells.

Symptoms

Symptoms of anaemia

Each type of anaemia has its own symptoms, which depend on what the underlying cause of the anaemia is. However, there are some more general symptoms, which are associated with all types of anaemia. These symptoms include:

  • fatigue,
  • breathlessness (dyspnoea)
  • faintness,
  • irregular heart beats (palpitations),
  • headache,
  • ringing in your ears (tinnitus), and
  • loss of appetite.


Vitamin B12 deficiency

If your anaemia is being caused by a vitamin B12 deficiency, you may also notice other symptoms, including:

  • yellow tinge to your skin (caused by jaundice, a condition which develops when a chemical called bilirubin builds up in the blood),
  • sore and red tongue (glossitis)
  • ulcers inside your mouth,
  • altered, or reduced, sense of touch,
  • reduced ability to feel pain,
  • change in the way you walk and move around,
  • disturbed vision,
  • irritability, and
  • depression.


Folate deficiency

As well as the general symptoms of anaemia, a folate deficiency may also cause:

  • loss of sensation,
  • inability to control your muscles, and
  • depression.

Causes

Causes of anaemia

Vitamin B12 deficiency anaemia

The body usually stores enough vitamin B12 to last for approximately two to four years. However, it is important that you have vitamin B12 in your diet in order to ensure that this store of the vitamin is kept at a healthy level.

Pernicious anaemia
In the UK, pernicious anaemia is the most common cause of vitamin B12 deficiency. Pernicious anaemia is an autoimmune disease that affects your stomach. An autoimmune disease is when the body’s immune system (which normally protects and fights against infection) starts to attack your body’s healthy cells.

Vitamin B12 is absorbed into your body through your stomach. The vitamin combines with a protein substance called ‘intrinsic factor’ so that it can be absorbed from the food that you eat. If your body does not produce enough intrinsic factor, it will not be able to absorb enough vitamin B12.

When your body does not produce enough intrinsic factor, and fails to absorb vitamin B12, it is known as pernicious anaemia. Pernicious anaemia causes your immune system to attack the cells in your stomach which produce the intrinsic factor. It is not known what triggers the immune system to attack the cells in this way.

Most people who have pernicious anaemia are over 60 years of age. The condition also tends to affect slightly more women than men. Around 30% of people with pernicious anaemia have a close family relative with the condition.

Other causes of vitamin B12 deficiency are rare. However, a deficiency can be caused by a number of other factors, some of which are outlined below.

Diet
Although it is rare in the UK, some people do not get enough vitamin B12 in their diet. Vegans are more likely to be affected, or those who have a very poor diet for a prolonged period of time.

Conditions affecting the stomach
Some stomach conditions, or procedures that are carried out on the stomach, can stop it absorbing enough vitamin B12. For example, a gastrectomy (where part of your stomach is removed) increases your risk of developing vitamin B12 deficiency anaemia.

Conditions affecting the intestines
Some conditions that affect your intestines stop you from absorbing as much vitamin B12 as normal. For example, Crohn’s disease (which causes inflammation in the gut), can sometimes result in your body not having enough vitamin B12.

Medication
Some types of medicine can reduce the amount of vitamin B12 in your body. Your GP will be aware of any medicines that can affect your vitamin B12 levels, and will monitor you if they feel that it is necessary.

Folate deficiency anaemia

Folate is a water-soluble vitamin, which means that your body is unable to store it for long periods of time. Your body’s stores of folate are usually only enough to last for four months. This means that you need to have folate in your daily diet to ensure that your body has sufficient stores of the vitamin.

Folate deficiency anaemia can also develop for a number of reasons, some of which are outlined below.

Diet
Some people do not have enough folate in their daily diet. This may be because they have recently changed their diet (perhaps to lose weight), or because their diet is not healthy and balanced.

Absorption
Sometimes, your body may be unable to absorb folate as effectively as it should. This is normally the result of an underlying condition, such as irritable bowel syndrome (IBS), which affects your digestive system.

Excessive urination
You may lose folate if you have to urinate very frequently because of an underlying condition that affects your kidney or liver, or other organs.

For example, congestive heart failure (where the heart is unable to pump enough blood around the body) can often cause you to urinate frequently. Acute liver damage (often as a result of drinking excessive amounts of alcohol) and long-term dialysis (where a special machine helps to filter the kidneys) can also cause you to lose excessive amounts of urine.

Medication
Some types of medicine can reduce the amount of folate in your body. Your GP will be aware of any medicines that can affect your folate levels, and will monitor you if they feel that it is necessary.

Other causes
Sometimes, your body requires more folate than normal. This can make you more prone to developing folate deficiency anaemia because you are unable to meet your body’s demands for the vitamin. Your body may need more folate than normal when you:

  • are pregnant,
  • have cancer,
  • have a blood disorder, such as sickle cell anaemia (a genetic disorder which causes your blood cells to change shape), or
  • have inflammation in your body


Premature babies are also more prone to developing folate deficiency anaemia because their developing bodies cannot meet the demand for the vitamin.

If you are pregnant, you should take a daily supplement of 0.4mg of folic acid for the first 12 weeks of your pregnancy. This will ensure that both you and your baby have enough folate, and it will help your baby to grow and develop. You can get folic acid tablets over-the-counter (OTC) from pharmacies, large supermarkets, and health food stores. They are also available on prescription.

If you have any of the other conditions mentioned above, which increase your body’s need for folate, your GP will be able to monitor your condition, to help prevent you from becoming anaemic.

Diagnosis

Diagnosing anaemia

To diagnose a vitamin B12 or folate deficiency, your GP will ask you to describe your symptoms and will look carefully at your medical history. They may also carry out a physical examination

Blood tests

If your GP suspects you have vitamin B12 or folate deficiency anaemia, they will usually require you to have a blood test in order to confirm the diagnosis. A sample of your blood will be taken and sent to a laboratory where a ‘full blood count’ test will be carried out.

If you have less haemoglobin than normal, you will be diagnosed with anaemia. Your blood can also be tested to see how much vitamin B12 and folate you have. If your tests show that you are deficient in either of these vitamins, it will help your GP to determine which type of anaemia you have.

Once your GP has determined that you have vitamin B12 or folate deficiency anaemia, they may have to carry out further tests to help establish the underlying cause of your deficiency.

For example, vitamin B12 deficiency is most commonly caused when the antibodies in your immune system (which usually protect against and fight infection) start to attack cells in your stomach, which help your body to absorb the vitamin. Your blood can be tested to see if it contains the antibodies which attack the stomach cells.

Once your GP has determined the underlying cause of your anaemia, they will be able to provide you with the most appropriate treatment.

Referral

In some circumstances, you may have to be referred for further testing, or treatment, with a specialist. Some of the specialists you may be referred to are outlined below.

Haematologist
A haematologist is a doctor who specialises in blood conditions. If you are pregnant and have been diagnosed with vitamin B12 or folate deficiency anaemia, you will be referred to a haematologist. This is because a vitamin B12 or folate deficiency can sometimes affect your developing baby.

You will also be referred to a haematologist if you are displaying symptoms which suggest that your nervous system has been affected by vitamin B12 or folate deficiency anaemia. These symptoms may include a reduced or altered sense of touch and pain, a change in your vision, or an inability to control your muscles.

If the cause of your vitamin B12 or folate deficiency is unknown, or if a more serious underlying cause is suspected, you may also be referred to a haematologist so that the cause of your deficiency can be investigated further.

Gastroenterologist
A gastroenterologist is a doctor who specialises in treating conditions that affect the digestive system. If your GP suspects that you do not have enough vitamin B12 or folate because your digestive system is not absorbing it properly, you may be referred to a gastroenterologist.

Dietician
A dietician is a health professional who specialises in nutrition. A dietician can give you advice about your diet, and inform you about ways that you can adapt and change it in order to help treat your condition.

If your vitamin B12 or folate deficiency is thought to be caused by a poor diet, you will be referred to a dietician, who will be able to devise a personalised eating plan to help increase the amount of vitamin B12 and folate that you eat.

Treatment

Treating anaemia

The treatment for your anaemia will depend on whether it is being caused by a lack of vitamin B12 or folate. The different treatments are outlined below.

Vitamin B12 deficiency anaemia

Vitamin B12 deficiency anaemia is usually treated using injections of vitamin B12. The vitamin is in the form of a substance known as hydroxocobalamin. At first, you will have injections every other day for two weeks. These injections will be given to you by your GP or nurse. After this, your dosage will depend on the cause of your vitamin B12 deficiency.

  • If your vitamin B12 deficiency is not caused by a lack of the vitamin in your diet, you will usually need to have an injection of hydroxocobalamin every three months for the rest of your life. Some people who have had neurological symptoms because of vitamin B12 deficiency will need injections every two months.
  • If your vitamin B12 deficiency is caused by a lack of the vitamin in your diet, you will be prescribed vitamin B12 tablets. People who may struggle to get enough vitamin B12 in their diets, such as vegans, may need to take vitamin B12 tablets for life. However, if this does not apply to you, your GP will be able to stop your tablets once your vitamin B12 levels return to normal.

Folate deficiency anaemia

To treat folate deficiency anaemia, your GP will normally prescribe folic acid tablets to help build up your folate levels. Most people will need to take these tablets for approximately four months.

However, if the underlying cause of your folate deficiency anaemia is persistent, you may have to take folic acid tablets for a longer period, and maybe for life.

Before you start taking folic acid, your GP will check your vitamin B12 levels to make sure that they are normal. This is because folic acid treatment can sometimes improve your symptoms so much that is masks an underlying vitamin B12 deficiency. If your B12 deficiency is not detected and treated, it could affect your nervous system.

Self-help

If you have been diagnosed with vitamin B12 or folate deficiency anaemia, there are some ways that you can treat the condition yourself. It is important to incorporate lots of vitamin B12 and folate in your everyday diet.

Increasing your vitamin B12 intake

Good sources of vitamin B12 are meat, eggs and dairy products. If you incorporate foods like this into a healthy, balanced diet, you should be able to increase your vitamin B12 intake.

If you are a vegetarian, or vegan, or you are looking for alternative to meat and dairy products, there are some other foods which contain vitamin B12. Some fortified breakfast cereals and some soy products contain vitamin B12. You can check the nutrition labels on these foods to see how much vitamin B12 they contain.

Increasing your folate intake

The best way to increase your intake of folate is to eat more green vegetables. Vegetables, such as broccoli, Brussels sprouts, asparagus, peas, chickpeas and brown rice all contain naturally high levels of folate.

Monitoring your condition

To ensure that your treatment is working, your vitamin B12 and folate levels will have to be monitored. Shortly after starting treatment, you will need to have a blood test to check that your treatment is starting to help restore your vitamin B12 and folate levels. You will then need another blood test after approximately eight weeks to confirm that your treatment has been successful.

Most people who have had a B12 or folate deficiency will not require further monitoring unless their symptoms return, or if their treatment is not proving to be effective. If your GP feels it necessary, you may have to return for an annual blood test, to check that your condition has not recurred.

Complications

Complications of anaemia

As most cases of vitamin B12 or folate deficiency can be easily and effectively treated, complications are relatively rare. However, in some cases, a deficiency in these vitamins can result in complications, particularly if you have been deficient in vitamin B12 or folate for some time.

In severe cases, any type of anaemia can cause you to develop complications which affect your heart and lungs, stopping them from working as well as they should. If your anaemia is severe, you may have to be admitted to hospital so that your heart and lungs can be carefully monitored. A lack of vitamin B12 or folate can also cause other complications, some of which are outlined below.

Complications of vitamin B12 deficiency

Nervous system
A lack of vitamin B12 can affect your nervous system. For example, you may experience problems with your vision, or have memory loss.

Fertility
Vitamin B12 deficiency can sometimes affect your fertility, and cause temporary sterility (an inabilty to conceive). However, you will not be sterile permanently, and the condition can be reversed using vitamin supplements.

Neural tube defects
If you are pregnant, not having enough vitamin B12 can increase the risk of you baby developing a neural tube defect. Neural tube defects affect your baby’s growth and development. Spina bifida (where the baby’s spine does not form properly) and anencephaly (where the baby’s brain and skull bones do not form properly) are both examples of neural tube defects.

Complications of folate deficiency

Fertility
As with a lack of vitamin B12, a deficiency of folate can also affect your fertility. However, the effects are only temporary, and can be reversed by using vitamin supplements.

Cardiovascular disease
Research has shown that a lack of folate in your body may increase your risk of developing cardiovascular disease. Cardiovascular disease is when your heart and the rest of your circulation system fail to work as well as they should.

Cancer
Research has shown that folate deficiency can be linked to some cancers. Although a lack of folate is never be the sole cause of a cancer developing, it may be a contributing factor.

Neural tube defects
As with a vitamin B12 deficiency, a lack of folate can also affect your baby’s growth and development in the womb, making them more prone to developing neural tube defects, such as spina bifida.

Premature birth
As well as affecting your baby’s growth, a lack of folate during your pregnancy may also increase the risk of your baby being born prematurely.

Useful links

NHS Choices links

External links

This article was originally published by NHS Choices

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