What are the main causes of vitamin B12 deficiency. How does pernicious anemia affect B12 absorption. What dietary factors can lead to folate deficiency. How do certain medical conditions impact B12 and folate levels. What treatments are available for B12 and folate deficiency anemia.

Understanding Vitamin B12 and Folate Deficiency Anemia

Vitamin B12 and folate deficiency anemia occurs when the body lacks sufficient amounts of these essential vitamins to produce fully functioning red blood cells. This condition, known as megaloblastic anemia, results in underdeveloped red blood cells that are larger than normal. Understanding the causes, symptoms, and treatment options for this type of anemia is crucial for maintaining optimal health.

What is megaloblastic anemia?

Megaloblastic anemia is a condition characterized by the production of abnormally large, immature red blood cells. These cells, called megaloblasts, are unable to carry oxygen efficiently throughout the body, leading to various symptoms and health complications.

Causes of Vitamin B12 Deficiency

Several factors can contribute to vitamin B12 deficiency, ranging from autoimmune conditions to dietary choices. Let’s explore the primary causes in detail:

Pernicious Anemia: The Most Common Cause

Pernicious anemia is the leading cause of vitamin B12 deficiency in the United Kingdom. This autoimmune condition affects the stomach and impairs the body’s ability to absorb vitamin B12.

How does pernicious anemia affect B12 absorption? In a healthy digestive system, vitamin B12 is combined with a protein called intrinsic factor in the stomach. This combination is then absorbed in the distal ileum, a part of the small intestine. However, in pernicious anemia, the immune system attacks the cells in the stomach that produce intrinsic factor, preventing the body from absorbing vitamin B12 effectively.

Who is at risk for pernicious anemia? The condition is more common in:

• Women around 60 years of age
• Individuals with a family history of the condition
• People with other autoimmune conditions, such as Addison’s disease or vitiligo

Dietary Factors

A diet lacking in vitamin B12 can lead to deficiency over time. Which foods are rich in vitamin B12? Meat, fish, and dairy products are excellent sources of this essential nutrient. Individuals who follow a vegan diet or do not regularly consume these foods are at risk of developing a deficiency.

It’s important to note that the body can store vitamin B12 for 2 to 5 years without replenishment. This means that dietary changes may not immediately result in deficiency symptoms, but long-term inadequate intake can eventually lead to health problems.

Gastrointestinal Conditions and Surgeries

Certain stomach conditions and surgical procedures can interfere with vitamin B12 absorption. For example, a gastrectomy, where part of the stomach is removed, increases the risk of vitamin B12 deficiency. Additionally, conditions affecting the intestines, such as Crohn’s disease, can impair the body’s ability to absorb sufficient amounts of vitamin B12.

Medications

Some medications can reduce the amount of vitamin B12 in the body. These include:

• Proton pump inhibitors (PPIs)
• Metformin
• Nitrous oxide

Healthcare providers are aware of these potential interactions and may monitor patients taking these medications for signs of vitamin B12 deficiency.

Functional Vitamin B12 Deficiency

In some cases, individuals may experience symptoms of vitamin B12 deficiency despite having normal blood levels of the vitamin. This condition, known as functional vitamin B12 deficiency, occurs due to problems with the proteins responsible for transporting vitamin B12 between cells. This can result in neurological complications involving the spinal cord.

Causes of Folate Deficiency

Folate, also known as vitamin B9, is another essential nutrient that plays a crucial role in red blood cell production. Unlike vitamin B12, folate is water-soluble and cannot be stored in the body for extended periods. Let’s examine the primary causes of folate deficiency:

Dietary Factors

A diet lacking in folate-rich foods is a common cause of deficiency. Which foods are high in folate? Good sources include:

• Broccoli
• Brussels sprouts
• Asparagus
• Peas
• Chickpeas
• Brown rice

Folate deficiency is more likely to occur in individuals who:

• Have an unbalanced or unhealthy diet
• Regularly misuse alcohol
• Follow a restrictive diet that excludes good sources of folate

Malabsorption

Sometimes, the body may be unable to absorb folate effectively due to underlying digestive conditions. Celiac disease, for example, can impair folate absorption in the intestines.

Excessive Urination

Certain medical conditions can cause excessive urination, leading to increased folate loss from the body. These conditions include:

• Congestive heart failure
• Acute liver damage (often caused by excessive alcohol consumption)
• Long-term dialysis

Symptoms of Vitamin B12 and Folate Deficiency Anemia

Recognizing the symptoms of vitamin B12 and folate deficiency anemia is crucial for early diagnosis and treatment. Common symptoms include:

• Extreme fatigue
• Shortness of breath
• Pale or yellowing skin
• Heart palpitations
• Loss of appetite
• Weight loss
• Mouth ulcers
• Muscle weakness
• Vision disturbances
• Mood changes (depression or irritability)

In cases of severe or prolonged deficiency, neurological symptoms may develop, such as:

• Numbness or tingling in the hands and feet
• Balance problems
• Confusion
• Memory loss
• Difficulty concentrating

Diagnosis of Vitamin B12 and Folate Deficiency Anemia

Diagnosing vitamin B12 and folate deficiency anemia typically involves a combination of medical history assessment, physical examination, and laboratory tests. The diagnostic process may include:

Blood Tests

A complete blood count (CBC) can reveal the presence of megaloblastic anemia. Additional tests to measure vitamin B12 and folate levels in the blood are often performed.

Intrinsic Factor Antibody Test

This test checks for antibodies against intrinsic factor, which can help diagnose pernicious anemia.

Methylmalonic Acid (MMA) Test

Elevated levels of MMA in the blood or urine can indicate vitamin B12 deficiency, even when blood levels of B12 appear normal.

Schilling Test

Although less commonly used today, this test can help determine if the body is absorbing vitamin B12 properly.

Treatment Options for Vitamin B12 and Folate Deficiency Anemia

The treatment approach for vitamin B12 and folate deficiency anemia depends on the underlying cause and severity of the condition. Common treatment options include:

Vitamin B12 Supplementation

For vitamin B12 deficiency, treatment typically involves vitamin B12 injections or high-dose oral supplements. The route of administration depends on the cause of the deficiency and the patient’s ability to absorb the vitamin.

Folate Supplementation

Folate deficiency is usually treated with oral folic acid supplements. In some cases, intravenous folate may be necessary.

Dietary Changes

Incorporating more vitamin B12 and folate-rich foods into the diet is essential for long-term management and prevention of deficiency.

Treating Underlying Conditions

If the deficiency is caused by an underlying medical condition, such as celiac disease or pernicious anemia, appropriate treatment for these conditions is necessary.

Prevention of Vitamin B12 and Folate Deficiency Anemia

Preventing vitamin B12 and folate deficiency anemia involves maintaining a balanced diet and addressing risk factors. Here are some prevention strategies:

Dietary Considerations

• Consume a varied diet rich in vitamin B12 and folate sources
• For vegetarians and vegans, consider fortified foods or supplements
• Limit alcohol consumption, as excessive alcohol intake can interfere with folate absorption

Regular Health Check-ups

Regular medical check-ups can help identify deficiencies early, especially for individuals at higher risk, such as older adults or those with gastrointestinal disorders.

Monitoring Medications

If you’re taking medications that may affect vitamin B12 or folate levels, discuss potential monitoring or supplementation with your healthcare provider.

Pregnancy Considerations

Pregnant women have increased folate requirements. Taking folic acid supplements before and during pregnancy can help prevent neural tube defects in the developing fetus.

Understanding the causes, symptoms, and treatment options for vitamin B12 and folate deficiency anemia is crucial for maintaining optimal health. By recognizing risk factors, adopting a balanced diet, and seeking prompt medical attention when symptoms arise, individuals can effectively manage and prevent these nutritional deficiencies. Regular health check-ups and open communication with healthcare providers play a vital role in early detection and appropriate management of vitamin B12 and folate deficiency anemia.

Vitamin B12 or folate deficiency anaemia – Causes

Vitamin B12 or folate deficiency anaemia occurs when a lack of either of these vitamins affects the body’s ability to produce fully functioning red blood cells.

Red blood cells carry oxygen around the body. Most people with vitamin B12 or folate deficiency anaemia have underdeveloped red blood cells that are larger than normal. The medical term for this is megaloblastic anaemia.

A vitamin B12 or folate deficiency can be the result of a variety of problems.

Causes of vitamin B12 deficiency

Pernicious anaemia

Pernicious anaemia is the most common cause of vitamin B12 deficiency in the UK.

Pernicious anaemia is an autoimmune condition that affects your stomach.

An autoimmune condition means your immune system, the body’s natural defence system that protects against illness and infection, attacks your body’s healthy cells.

Vitamin B12 is combined with a protein called intrinsic factor in your stomach. This mix of vitamin B12 and intrinsic factor is then absorbed into the body in part of the gut called the distal ileum.

Pernicious anaemia causes your immune system to attack the cells in your stomach that produce the intrinsic factor, which means your body is unable to absorb vitamin B12.

The exact cause of pernicious anaemia is unknown, but it’s more common in women around 60 years of age, people with a family history of the condition and those with another autoimmune condition, such as Addison’s disease or vitiligo.

Diet

Some people can develop a vitamin B12 deficiency as a result of not getting enough vitamin B12 from their diet.

A diet that includes meat, fish and dairy products usually provides enough vitamin B12, but people who do not regularly eat these foods can become deficient.

People who eat a vegan diet and do not take vitamin B12 supplements or eat foods fortified with vitamin B12, are also at risk.

Stores of vitamin B12 in the body can last around 2 to 5 years without being replenished, so it can take a long time for any problems to develop after a dietary change.

Conditions affecting the stomach

Some stomach conditions or stomach operations can prevent the absorption of enough vitamin B12.

For example, a gastrectomy, a surgical procedure where part of your stomach is removed, increases your risk of developing a vitamin B12 deficiency.

Conditions affecting the intestines

Some conditions that affect your intestines can also stop you absorbing the necessary amount of vitamin B12.

For example, Crohn’s disease, a long-term condition that causes inflammation of the lining of the digestive system, can sometimes mean your body does not get enough vitamin B12.

Medicines

Some types of medicine can lead to a reduction in the amount of vitamin B12 in your body.

Examples include:

• proton pump inhibitors (PPIs)
• metformin
• nitrous oxide

Your GP will be aware of medicines that can affect your vitamin B12 levels and will monitor you if necessary.

Functional vitamin B12 deficiency

Some people can experience problems related to a vitamin B12 deficiency, despite appearing to have normal levels of vitamin B12 in their blood.

This can happen as the result of a problem known as functional vitamin B12 deficiency, where there’s a problem with the proteins that help transport vitamin B12 between cells.

This results in neurological complications involving the spinal cord.

Causes of folate deficiency

Folate dissolves in water, which means your body is unable to store it for long periods of time.

Your body’s store of folate is usually enough to last 4 months. This means you need folate in your daily diet to ensure your body has sufficient stores of the vitamin.

Like vitamin B12 deficiency anaemia, folate deficiency anaemia can develop for a number of reasons.

Diet

Good sources of folate include broccoli, Brussels sprouts, asparagus, peas, chickpeas and brown rice.

If you do not regularly eat these types of foods, you may develop a folate deficiency.

Folate deficiency caused by a lack of dietary folate is more common in people who have a generally unbalanced and unhealthy diet, people who regularly misuse alcohol, and people following a restrictive diet that does not involve eating good sources of folate.

Malabsorption

Sometimes your body may be unable to absorb folate as effectively as it should. This is usually caused by an underlying condition affecting your digestive system, such as coeliac disease.

Excessive peeing

You may lose folate from your body if you pee frequently.

This can be caused by an underlying condition that affects one of your organs, such as:

• congestive heart failure – where the heart is unable to pump enough blood around the body
• acute liver damage – often caused by drinking excessive amounts of alcohol
• long-term dialysis – where a machine that replicates the kidney function is used to filter waste products from the blood

Medicine

Some types of medicines reduce the amount of folate in your body or make the folate harder to absorb.

These include some anticonvulsants (medicines used to treat epilepsy), colestyramine, sulfasalazine and methotrexate.

Your GP will be aware of medicines that can affect your folate levels and will monitor you if necessary.

Other causes

Your body sometimes requires more folate than normal. This can cause folate deficiency if you cannot meet your body’s demands for the vitamin.

Your body may need more folate than usual if you:

• are pregnant – read more about complications of folate deficiency in pregnancy
• have cancer
• have a blood disorder – such as sickle cell anaemia, an inherited blood disorder that causes red blood cells to develop abnormally
• are fighting an infection or health condition that causes inflammation (redness and swelling)

Premature babies (born before the 37th week of pregnancy) are also more likely to develop a folate deficiency because their developing bodies require higher amounts of folate than normal.

Page last reviewed: 20 February 2023
Next review due: 20 February 2026

Vitamin B12 & folate anaemia – Illnesses & conditions

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   Causes of vitamin B12 or folate deficiency anaemia
   
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About 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 can’t 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, iron deficiency anaemia, which occurs when the body doesn’t contain enough iron.

Symptoms of vitamin B12 or folate deficiency

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
• mouth ulcers
• muscle weakness
• disturbed vision
• psychological problems, which may include depression and confusion 
• problems with memory, understanding and judgement

Some of these problems can also occur if you have a deficiency in vitamin B12 or folate, but don’t have anaemia.

Read about the symptoms of vitamin B12 or folate deficiency anaemia

When to see your GP

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 improve with treatment, some problems caused by the condition can be irreversible.

Read about diagnosing vitamin B12 or folate deficiency anaemia

Causes of a vitamin B12 or folate deficiency

There are a number of problems that can lead to a vitamin B12 or folate deficiency, including:

• pernicious anaemia – where your immune system attacks healthy cells in your stomach, preventing your body from absorbing vitamin B12 from the food you eat; this is the most common cause of vitamin B12 deficiency in the UK
• a lack of these vitamins in your diet – this is uncommon, but can occur if you have a vegan diet, follow a fad diet or have a generally poor diet for a long time
• medication – certain medications, including anticonvulsants and proton pump inhibitors (PPIs), can affect how much of these vitamins your body absorbs 

Both vitamin B12 deficiency and folate deficiency are more common in older people, affecting around 1 in 10 people aged 75 or over, and 1 in 20 people aged 65 to 74.

Read about the causes of vitamin B12 or folate deficiency anaemia

Treating vitamin B12 or folate deficiency anaemia

Most cases of vitamin B12 and folate deficiency can be easily treated with injections or tablets to replace the missing vitamins.

Vitamin B12 supplements are usually given by injection at first. Then, depending on whether your B12 deficiency is related to your diet, you’ll either require B12 tablets between meals or regular injections. These treatments may be needed for the rest of your life.

Folic acid tablets are used to restore folate levels. These usually need to be taken for four months.

In some cases, improving your diet can help treat the condition and prevent it recurring. Vitamin B12 is found in meat, fish, eggs, dairy products, yeast extract (such as Marmite) and specially fortified foods. The best sources of folate include green vegetables such as broccoli, Brussels sprouts and peas.

Read about treating vitamin B12 or folate deficiency

Complications of vitamin B12 or folate deficiency anaemia

Although it’s uncommon, vitamin B12 or folate deficiency (with or without anaemia) can lead to complications, particularly if you’ve been deficient in vitamin B12 or folate for some time.

Potential complications can include:

• problems with the nervous system
• temporary infertility
• heart conditions
• pregnancy complications and birth defects

Adults with severe anaemia are also at risk of developing heart failure.

Some complications improve with appropriate treatment, but others – such as problems with the nervous system – can be permanent. 

Read about the complications of vitamin B12 or folate deficiency anaemia

Symptoms of vitamin B12 or folate deficiency anaemia

Vitamin B12 or folate deficiency anaemia can cause a wide range of symptoms. These usually develop gradually but can worsen if the condition goes untreated.

Anaemia is where you have fewer red blood cells than normal or you have an abnormally low amount of a substance called haemoglobin in each red blood cell. General symptoms of anaemia may include:

• extreme tiredness (fatigue)
• lack of energy (lethargy)
• breathlessness
• feeling faint
• headaches
• pale skin
• noticeable heartbeats (palpitations)
• hearing sounds coming from inside the body, rather than from an outside source (tinnitus)
• loss of appetite and weight loss

Symptoms of vitamin B12 deficiency

If you have anaemia caused by a vitamin B12 deficiency, you may have other symptoms in addition to those listed above, such as:

• a pale yellow tinge to your skin
• a sore and red tongue (glossitis)
• mouth ulcers
• pins and needles (paraesthesia)
• changes in the way that you walk and move around
• disturbed vision
• irritability
• depression
• changes in the way you think, feel and behave
• a decline in your mental abilities, such as memory, understanding and judgement (dementia)

Some of these symptoms can also occur in people who have a vitamin B12 deficiency, but have not developed anaemia.

Symptoms of folate deficiency

Additional symptoms in people with anaemia caused by a folate deficiency can include:

• symptoms related to anaemia
• reduced sense of taste
• diarrhoea
• numbness and tingling in the feet and hands
• muscle weakness
• depression

When to see your GP

See your GP if you’re experiencing symptoms of vitamin B12 or folate deficiency anaemia. These conditions can often be diagnosed based on your symptoms and the results of a blood test.

Read more about diagnosing vitamin B12 or folate deficiency anaemia

It’s important for vitamin B12 or folate deficiency anaemia to be diagnosed and treated as soon as possible. Although many of the symptoms improve with treatment, some problems caused by the condition can be irreversible if left untreated. The longer the condition goes untreated, the higher the chance of permanent damage.

Causes of vitamin B12 or folate deficiency anaemia

Vitamin B12 or folate deficiency anaemia occurs when a lack of either of these vitamins affects the body’s ability to produce fully functioning red blood cells.

Red blood cells carry oxygen around the body. Most people with vitamin B12 or folate deficiency anaemia have underdeveloped red blood cells that are larger than normal. The medical term for this is “megaloblastic anaemia”.

A vitamin B12 or folate deficiency can be the result of a variety of problems, some of which are described below.

Causes of vitamin B12 deficiency

Pernicious anaemia

Pernicious anaemia is the most common cause of vitamin B12 deficiency in the UK.

Pernicious anaemia is an autoimmune condition that affects your stomach. An autoimmune condition means your immune system (the body’s natural defence system that protects against illness and infection) attacks your body’s healthy cells.

In your stomach, vitamin B12 is combined with a protein called intrinsic factor. This mix of vitamin B12 and intrinsic factor is then absorbed into the body in part of the gut called the distal ileum.

Pernicious anaemia causes your immune system to attack the cells in your stomach that produce the intrinsic factor, which means your body is unable to absorb vitamin B12.

The exact cause of pernicious anaemia is unknown, but the condition is more common in women around 60 years of age, people with a family history of the condition and those with another autoimmune condition, such as Addison’s disease or vitiligo.

Diet

Some people can develop a vitamin B12 deficiency as a result of not getting enough vitamin B12 from their diet.

A diet that includes meat, fish and dairy products usually provides enough vitamin B12, but people who don’t regularly eat these foods – such as those following a vegan diet or who have a generally very poor diet – can become deficient.

Stores of vitamin B12 in the body can last around two to four years without being replenished, so it can take a long time for any problems to develop after a dietary change.

Conditions affecting the stomach

Some stomach conditions or stomach operations can prevent the absorption of enough vitamin B12.

For example, a gastrectomy (a surgical procedure where part of your stomach is removed) increases your risk of developing a vitamin B12 deficiency.

Conditions affecting the intestines

Some conditions that affect your intestines can also stop you from absorbing the necessary amount of vitamin B12.

For example, Crohn’s disease (a long-term condition that causes inflammation of the lining of the digestive system) can sometimes mean your body doesn’t get enough vitamin B12.

Medication

Some types of medicine can lead to a reduction in the amount of vitamin B12 in your body.

For example, proton pump inhibitors (PPIs) – a medication sometimes used to treat indigestion – can make a vitamin B12 deficiency worse. PPIs inhibit the production of stomach acid, which is needed to release vitamin B12 from the food you eat.

Your GP will be aware of medicines that can affect your vitamin B12 levels and will monitor you if necessary.

Functional vitamin B12 deficiency

Some people can experience problems related to a vitamin B12 deficiency, despite appearing to have normal levels of vitamin B12 in their blood.

This can occur due to a problem known as functional vitamin B12 deficiency – where there’s a problem with the proteins that help transport vitamin B12 between cells. This results in neurological complications involving the spinal cord.

Causes of folate deficiency

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

Like vitamin B12 deficiency anaemia, folate deficiency anaemia can develop for a number of reasons. Some are described below.

Diet

Good sources of folate include broccoli, Brussels sprouts, asparagus, peas, chickpeas and brown rice. If you don’t regularly eat these types of foods, you may develop a folate deficiency.

Folate deficiency caused by a lack of dietary folate is more common in people who have a generally unbalanced and unhealthy diet, people who regularly misuse alcohol and people following a fad diet that doesn’t involve eating good sources of folate.

Malabsorption

Sometimes your body may be unable to absorb folate as effectively as it should. This is usually due to an underlying condition affecting your digestive system, such as coeliac disease.

Excessive urination

You may lose folate from your body if you urinate frequently. This can be caused by an underlying condition that affects one of your organs, such as:

• congestive heart failure – where the heart is unable to pump enough blood around the body
• acute liver damage – often caused by drinking excessive amounts of alcohol
• long-term dialysis – where a machine that replicates the kidney function is used to filter waste products from the blood

Medication

Some types of medicine reduce the amount of folate in your body, or make the folate harder to absorb.

These include some anticonvulsants (medication used to treat epilepsy), colestyramine, sulfasalazine and methotrexate.

Your GP will be aware of medicines that can affect your folate levels and will monitor you if necessary.

Other causes

Your body sometimes requires more folate than normal. This can cause folate deficiency if you can’t meet your body’s demands for the vitamin.

Your body may need more folate than usual if you:

• are pregnant (see below)
• have cancer
• have a blood disorder – such as sickle cell anaemia (an inherited blood disorder which causes red blood cells to develop abnormally)
• are fighting an infection or health condition that causes inflammation (redness and swelling)

Premature babies (born before the 37th week of pregnancy) are also more likely to develop a folate deficiency, because their developing bodies require higher amounts of folate than normal.

Pregnancy

If you’re pregnant or trying to get pregnant, it’s recommended that you take a 400 microgram folic acid tablet every day until you’re 12 weeks pregnant. This will ensure that both you and your baby have enough folate and help your baby grow and develop.

Folic acid tablets are available with a prescription from your GP, or you can buy them over the counter from pharmacies, large supermarkets and health food stores.

If you’re pregnant and have another condition that may increase your body’s need for folate, such as those mentioned above, your GP will monitor you closely to prevent you from becoming anaemic.

In some cases, you may need a higher dose of folic acid. For example, if you have diabetes, you should take a 5 milligrams (5mg) supplement of folic acid instead of the standard 400 micrograms.

Read more about vitamins and minerals in pregnancy

Diagnosing vitamin B12 or folate deficiency anaemia

A diagnosis of vitamin B12 or folate deficiency anaemia can often be made by your GP based on your symptoms and the results of blood tests.

Blood tests

Different types of blood tests can be carried out to help identify people with a possible vitamin B12 or folate deficiency. These tests check:

• whether you have a lower level of haemoglobin (a substance that transports oxygen) than normal
• whether your red blood cells are larger than normal
• the level of vitamin B12 in your blood
• the level of folate in your blood

However, some people can have problems with their normal levels of these vitamins or may have low levels despite having no symptoms.  This is why it’s important for your symptoms to be taken into account when a diagnosis is made.

A particular drawback of testing vitamin B12 levels is that the current widely-used blood test only measures the total amount of vitamin B12 in your blood.

This means it measures forms of vitamin B12 that are “active” and can be used by your body, as well as the “inactive” forms, which can’t. If a significant amount of the vitamin B12 in your blood is “inactive”, a blood test may show that you have normal B12 levels, even though your body can’t use much of it.

There are some types of blood test that may help determine if the vitamin B12 in your blood can be used by your body, but these aren’t yet widely available.

Identifying the cause

If your symptoms and blood test results suggest a vitamin B12 or folate deficiency, your GP may arrange further tests. If the cause can be identified, it will help to determine the most appropriate treatment.

For example, you may have additional blood tests to check for a condition called pernicious anaemia. This is an autoimmune condition (where your immune system produces antibodies to attack healthy cells), which means you’re unable to absorb vitamin B12 from the food you eat.

Tests for pernicious anaemia aren’t always conclusive, but they can often give your GP a good idea of whether you have the condition.

Referral to a specialist

You may be referred to a specialist for further tests or treatment. This may include:

• a haematologist (specialist in treating blood conditions) – if you have vitamin B12 or folate deficiency anaemia and your GP is uncertain of the cause, you’re pregnant or symptoms suggest your nervous system has been affected
• a gastroenterologist (specialist in conditions that affect the digestive system) – if your GP suspects you don’t have enough vitamin B12 or folate because your digestive system isn’t absorbing it properly
• a dietitian (specialist in nutrition) – if your GP suspects you have a vitamin B12 or folate deficiency caused by a poor diet

A dietitian can devise a personalised eating plan for you to increase the amount of vitamin B12 or folate in your diet.

Treating vitamin B12 or folate deficiency anaemia

The treatment for vitamin B12 or folate deficiency anaemia depends on what’s causing the condition. Most people can be easily treated with injections or tablets to replace the missing vitamins.

Treating vitamin B12 deficiency anaemia

Vitamin B12 deficiency anaemia is usually treated with injections of vitamin B12, in a form called hydroxocobalamin.

At first, you’ll have these injections every other day for two weeks, or until your symptoms have stopped improving. Your GP or nurse will give the injections.

After this initial period, your treatment will depend on whether the cause of your vitamin B12 deficiency is related to your diet. The most common cause of vitamin B12 deficiency in the UK is pernicious anaemia, which isn’t related to your diet.

Read more about the causes of vitamin B12 or folate deficiency

Diet-related

If your vitamin B12 deficiency is caused by a lack of the vitamin in your diet, you may be prescribed vitamin B12 tablets to take every day between meals. Alternatively, you may need to have an injection of hydroxocobalamin twice a year.

People who find it difficult to get enough vitamin B12 in their diets, such as those following a vegan diet, may need vitamin B12 tablets for life.

Although it’s less common, people with vitamin B12 deficiency caused by a prolonged poor diet may be advised to stop taking the tablets once their vitamin B12 levels have returned to normal and their diet has improved.

Good sources of vitamin B12 include:

• meat
• salmon and cod
• milk and other dairy products
• eggs

If you’re a vegetarian and vegan, or are looking for alternatives to meat and dairy products, there are other foods that contain vitamin B12, such as yeast extract (including Marmite), as well as some fortified breakfast cereals and soy products.

Check the nutrition labels while food shopping to see how much vitamin B12 different foods contain.

Not diet-related

If your vitamin B12 deficiency isn’t caused by a lack of vitamin B12 in your diet, you’ll usually need to have an injection of hydroxocobalamin every three months for the rest of your life.

If you’ve had neurological symptoms (symptoms that affect your nervous system, such as numbness or tingling in your hands and feet) caused by a vitamin B12 deficiency, you’ll be referred to a haematologist, and you may need to have injections every two months. Your haematologist will advise on how long you need to keep taking the injections.

For injections of vitamin B12 given in the UK, hydroxocobalamin is preferred to an alternative called cyanocobalamin. This is because hydroxocobalamin stays in the body for longer.

If you need regular injections of vitamin B12, cyanocobalamin would need to be given once a month, whereas hydroxocobalamin can be given every three months.

Cyanocobalamin injections aren’t routinely available on the NHS. However, if you need replacement tablets of vitamin B12, these will be cyanocobalamin.

Treating folate deficiency anaemia

To treat folate deficiency anaemia, your GP will usually prescribe daily folic acid tablets to build up your folate levels. They may also give you dietary advice so you can increase your folate intake.

Good sources of folate include:

• broccoli
• Brussels sprouts
• asparagus
• peas
• chickpeas
• brown rice

Most people need to take folic acid tablets for about four months. However, if the underlying cause of your folate deficiency anaemia continues, you may have to take folic acid tablets for longer – possibly for life.

Before you start taking folic acid, your GP will check your vitamin B12 levels to make sure they’re normal. This is because folic acid treatment can sometimes improve your symptoms so much that it masks an underlying vitamin B12 deficiency.

If a vitamin B12 deficiency isn’t detected and treated, it could affect your nervous system.

Monitoring your condition

To ensure your treatment is working, you may need to have further blood tests.

A blood test is often carried out around 10-14 days after starting treatment to assess whether treatment is working. This is to check your haemoglobin level and the number of the immature red blood cells (reticulocytes) in your blood.

Another blood test may also be carried out after approximately eight weeks to confirm your treatment has been successful.

If you’ve been taking folic acid tablets, you may be tested again once the treatment has finished (usually after four months).

Most people who have had a vitamin B12 or folate deficiency won’t need further monitoring unless their symptoms return, or their treatment is ineffective. If your GP feels it’s necessary, you may have to return for an annual blood test to see whether your condition has returned.

Complications of vitamin B12 or folate deficiency anaemia

As most cases of vitamin B12 deficiency or folate deficiency can be easily and effectively treated, complications are rare.

However, complications can occasionally develop, particularly if you’ve been deficient in either vitamin for some time.

Anaemia complications

All types of anaemia, regardless of the cause, can lead to heart and lung complications as the heart struggles to pump oxygen to the vital organs.

Adults with severe anaemia are at risk of developing:

• an abnormally fast heart beat (tachycardia)
• heart failure – where the heart fails to pump enough blood around the body at the right pressure

Complications of vitamin B12 deficiency

A lack of vitamin B12 (with or without anaemia) can cause the following complications:

Neurological changes

A lack of vitamin B12 can cause neurological problems (issues affecting your nervous system), such as:

• vision problems
• memory loss
• pins and needles (paraesthesia)
• loss of physical coordination (ataxia), which can affect your whole body and cause difficulty speaking or walking
• damage to parts of the nervous system (peripheral neuropathy), particularly in the legs

If neurological problems do develop, they may be irreversible.

Infertility

Vitamin B12 deficiency can sometimes lead to temporary infertility (an inability to conceive). This usually improves with appropriate vitamin B12 treatment.

Stomach cancer

If you have a vitamin B12 deficiency caused by pernicious anaemia (a condition where your immune system attacks healthy cells in your stomach), your risk of developing stomach cancer is increased.

Neural tube defects

If you’re pregnant, not having enough vitamin B12 can increase the risk of your baby developing a serious birth defect known as a neural tube defect. The neural tube is a narrow channel that eventually forms the brain and spinal cord. 

Examples of neural tube defects include:

• spina bifida – where the baby’s spine doesn’t develop properly
• anencephaly – where a baby is born without parts of the brain and skull
• encephalocele – where a membrane or skin-covered sac containing part of the brain pushes out of a hole in the skull

Complications of folate deficiency

A lack of folate (with or without anaemia) can also cause complications, some of which are outlined below.

Infertility

As with a lack of vitamin B12, a folate deficiency can also affect your fertility. However, this is only temporary and can usually be reversed with folate supplements.

Cardiovascular disease

Research has shown a lack of folate in your body may increase your risk of cardiovascular disease (CVD).

CVD is a general term that describes a disease of the heart or blood vessels, such as coronary heart disease (CHD).

Cancer

Research has shown that folate deficiency can increase your risk of some cancers, such as colon cancer.

Problems in childbirth

A lack of folate during pregnancy may increase the risk of the baby being born prematurely (before the 37th week of pregnancy) or having a low birthweight.

The risk of placental abruption may also be increased. This is a serious condition where the placenta starts to come away from the inside of the womb wall, causing tummy (abdominal) pain and bleeding from the vagina.

Neural tube defects

As with a vitamin B12 deficiency, a lack of folate can also affect an unborn baby’s growth and development in the womb (uterus). This increases the risk of neural tube defects such as spina bifida developing in the unborn baby.

one of them interferes with sleep – Teacher’s newspaper

Vitamin B12 deficiency is a condition caused by an improper diet or the inability of the body to absorb a valuable substance in full. People who ignore warning signs are at risk of being hit. Vitamin B12 deficiency, if left uncorrected, can cause neurological, mental, and physical problems.

Photo: freepik.com

Everyone needs vitamins. The lack of each substance becomes a threat to human health. Therefore, it is so important to monitor their regular intake in the body.

One of the most valuable vitamins – B12 or cyanocobalamin – is involved in the formation of red blood cells, maintains the health of nerve cells, monitors the production of DNA – the body’s genetic material.

In its initial stages, vitamin B12 deficiency is not a serious disease. But this condition can turn into a serious illness if ignored and left untreated for too long.

In one of the scientific studies involving a large group of volunteers with signs of anemia, physicians found a common symptom. Patients spoke of him as an enemy who methodically pursues them at night. The night sweats that study participants complained about were found to be vitamin B12 deficiency upon further study of the volunteers’ stories.

Patient reports

A nocturnal symptom associated with cyanocobalamin deficiency was reported in 2015 by the European Journal of General Medicine. The situations described in the publication told of three patients who were exhausted by profuse night sweats and weakness, which accompanied an unhealthy condition.

The first case involved a 57-year-old man who suffered from a similar symptom for three to four years. According to him, every night he had to change the sheet, wet from sweat, to dry. After taking the supplements, the patient’s condition was assessed by the doctors as satisfactory: nocturnal symptoms disappeared.

In a similar case, a 74-year-old woman reported 10 years of episodic sweating, also requiring frequent changes of clothing and sheets. She was diagnosed with vitamin B12 deficiency due to elevated homocysteine ​​levels. After the injections, which were carried out in courses, there was a noticeable improvement in the general condition. The debilitating night signs disappeared.

The third case was in a 43-year-old man who had suffered from night sweats for four years, mainly affecting the head and face. In his situation, the supplements prescribed by the doctor helped.

Photo: pixabay.com

Vitamin B12 deficiency symptoms

Dr. Justin Butler, who led the study, believes B12 deficiency can cause permanent nerve damage and heart failure. Among the symptoms associated with a lack of cyanocobalamin, he named:

• severe fatigue;
• muscle weakness;
• depression;
• weight loss;
• yellowish skin tone;
• numbness or tingling in limbs;
• cognitive problems.

The expert drew attention to another characteristic sign indicating vitamin B12 deficiency: tinnitus. Patients reporting this symptom described it as sounds coming from within the body rather than from an outside source, Express reports.

In recent materials of the online publication Uchitelskaya Gazeta, other symptoms of cyanocobalamin deficiency are also described. And also about how to determine the deficiency of B12 in the face and find out the lack of a trace element in the eyes. Information about vitamin B12 can be found in a special UG.RU section dedicated to this topic.

A lot of useful information related to vitamins can be found here. We advise everyone who monitors their health to read the materials of special sections: About nutrition, Health.

This material is for informational purposes only. The purpose of the publication is to tell about the discoveries of scientists. All actions related to taking medications and dietary supplements must be agreed with the doctors.

Vitamin B12 (cyanocobalamin)

Vitamin B ₁₂ is a water-soluble vitamin that plays an important role in the normal functioning of the nervous system and the formation of blood cells. Its deficiency can cause serious changes in the body.

Synonyms Russian

Cobalamin, antianemic vitamin.

English synonyms

Cobalamin, cyanocobalamin.

Test method

Immunochemiluminescent assay.

Detection range: 100 – 4000 pg/ml.

Units

Pg/mL (picograms per milliliter).

What biomaterial can be used for research?

Venous blood.

How to properly prepare for an examination?

1. Do not eat for 2-3 hours before the examination, you can drink pure non-carbonated water.
2. Avoid physical and emotional stress and do not smoke for 30 minutes prior to the examination.

General information about the study

Determination of the concentration of vitamin B ₁₂ in blood serum is a standard method for diagnosing its deficiency.

Vitamin B ₁₂ is found exclusively in animal products such as meat (especially liver and kidney), fish, eggs, dairy products. In recent years, an important source of vitamin B ₁₂ , especially for vegetarians, has become fortified cereals, bread, breakfast cereals and other grain products.

B ₁₂ is important for nucleic acid synthesis, red blood cell formation, cell and tissue metabolism, and is also involved in maintaining the normal functioning of the nervous system. Vitamin B deficiency ₁₂ can lead to the development of macrocytic (megaloblastic) anemia. Its main manifestation is a decrease in the number of erythrocytes in the blood, but an increase in their size – the formation of macrocytes. Macrocytes tend to have a shorter lifespan than normal red blood cells and are more prone to hemolysis, leading to fatigue, weakness, and other symptoms of anemia. Vitamin B 9 deficiency0065 12 threatens to damage the nervous system (funicular myelosis), which manifests itself in the form of tingling in the legs and arms of the patient (distal paresthesia), sensitivity disorder, increased tendon reflexes.

Main causes of vitamin B deficiency ₁₂ in the body

• Insufficient intake. In ₁₂ accumulates mainly in the liver and spleen. Since the reserves of this vitamin in the body are quite large, and excretion is slow, it takes about 5 years of insufficient intake of it in the body to create a significant deficiency. Accordingly, the risk groups are starving people and vegetarians.

• Malabsorption. Deficiency of B ₁₂ sometimes occurs with various diseases of the small intestine that impair the absorption of this vitamin (celiac disease, Crohn’s disease, decreased acidity of gastric juice (achlorhydria), as well as with a decrease in the reabsorbent surface after resection of the jejunum. However, the most common cause of deficiency of B ₁₂ – pernicious anemia This disease is based on the congenital inability of the stomach to secrete a substance necessary for the absorption of vitamin B ₁₂ in the intestines.

• Violation of disposal. Various diseases of the liver and kidneys, as well as alcohol abuse, lead to a decrease in accumulation and an increase in the excretion of vitamin B ₁₂ .

• Increasing the body’s need for a vitamin. For various diseases that require a large amount of vitamin B ₁₂ , such as hemolytic anemia, hyperthyroidism and alpha thalassemia.

What is research used for?

• First of all, to identify the causes of macrocytic anemia.
• To assess the health and nutritional status of patients with signs of malnutrition and malabsorption, people suffering from alcoholism or various forms of malabsorption (celiac disease, Crohn’s disease).
• For older people, the B test ₁₂ can help determine the cause of mental and behavioral changes.
• Patients suffering from vitamin B 9 deficiency0065 12 , regular determination of its concentration allows you to control the treatment process. This is especially true for people with congenital defects in the absorption of vitamin B ₁₂ , who are forced to take drugs all their lives.

When is the test ordered?

• If a complete blood count, performed routinely or as part of the diagnosis of symptoms of anemia, reveals enlarged red blood cells.
• When identifying the causes of changes in behavior: the appearance of irritability, confusion, depression and / or paranoia (especially in the elderly).
• For non-specific symptoms indicating vitamin B deficiency ₁₂ such as dizziness, weakness, fatigue, gastrointestinal changes (glossitis, liver enlargement).
• If necessary, test for B deficiency ₁₂ patients with various neurological disorders: paresthesia and numbness of the hands and/or legs, sensory disturbance, peripheral neuropathy.
• When examining the health of patients with suspected malnutrition or malabsorption of vitamin B ₁₂ , for various bowel diseases.
• When B ₁₂ deficiency is found in a breastfed infant, the mother should be examined for deficiency of this vitamin.
• Periodic monitoring of the level of B ₁₂ allows you to evaluate the effectiveness of the treatment of beriberi.

What do the results mean?

Reference values: 197 – 771 pg/ml.

Decreased vitamin B concentration ₁₂ is highly likely to indicate a deficiency, but does not necessarily reflect the severity of anemia or neuropathy.

Increased vitamin B levels ₁₂ usually not clinically controlled. It can occur with leukemia or liver dysfunction.

Causes of low vitamin B levels ₁₂

• Pernicious anemia is a disease caused by impaired hematopoiesis due to a lack of vitamin B in the body ₁₂ . It is based on the congenital inability of the stomach to secrete intrinsic factor – a complex compound produced by additional cells of the stomach, necessary for the absorption of vitamin B ₁₂ in the intestines.
• Loss of vitamin in helminthic invasions (wide tapeworm).
• Pregnancy (more often in the last trimester).
• Total or partial gastrectomy.
• Atrophic gastritis.
• Inflammatory bowel disease (Crohn’s disease, ulcerative colitis, regional enteritis).
• Intestinal disorders associated with malabsorption (celiac disease, sprue).
• Congenital absence of transcobalamin-2, due to which the absorption and transport of vitamin B 9 is impaired0065 12 .
• Tuberculosis of the ileum.
• Lymphoma of the small intestine.

Causes of increased vitamin B levels ₁₂

• Acute and chronic myelogenous leukemia.
• Liver diseases (acute and chronic hepatitis, cirrhosis, hepatic coma). Violation of the deposition of vitamin B ₁₂ in the liver.
• Polycythemia vera is a malignant disease of the hematopoietic system, accompanied by hyperplasia of the cellular elements of the bone marrow and an increase in the level of serum vitamin B ₁₂ .

What can influence the result?

• The level of vitamin B ₁₂ decreases with its lack of food (vegetarianism) and alcohol abuse.
• Oral contraceptives, colchicine, anticonvulsants, antibiotics lower B concentration ₁₂ .
• If the patient is receiving only folic acid supplements with a simultaneous vitamin B deficiency ₁₂ and folic acid, the vitamin B level is ₁₂ may be normal or elevated.

Important Notes

• If a B deficiency is suspected ₁₂ , a folic acid test should be performed as levels are often interrelated.
• Vitamin B levels ₁₂ may be elevated if treated with vitamin B preparations incorrectly ₁₂ .