How do you recognize a vitamin B12 deficiency?

Veröffentlicht am: October 28, 2024
Dr. med. Wolfgang Bachmann
Dr. med. Wolfgang Bachmann

General practitioner

Are you getting enough vitamin B12? To stay healthy, you should make sure you get enough. Vitamin B12 is needed in the body in many ways, for example for DNA synthesis and the formation of red blood cells. A deficiency has a direct effect on our body. We suffer from tiredness, weakness, depression, tingling in our hands and feet, impaired vision and a generally weakened circulatory system. A deficiency can develop into irreversible nerve damage, so take early preventative action!

The most important facts about vitamin B12 deficiency summarized:

  • If there is a deficiency, the body does not have enough healthy red blood cells.
  • This is one of many forms of megaloblastic anemia.
  • Without sufficient red blood cells, body tissues and organs are not supplied with enough oxygen. Without sufficient oxygen, bodily functions cannot be maintained.
  • Symptoms include weak muscles, numbness, difficulty walking, nausea, weight loss, irritability, fatigue and an increased heart rate.
  • The symptoms are treated with vitamin B12 supplements, for example. A balanced diet also contributes to relief.

Contents  

What is vitamin B12?

Vitamin B12 is an essential, i.e. vital, water-soluble vitamin. This means that the body absolutely needs it to maintain important bodily functions. As a supplement, the vitamin is often taken together with other B vitamins. 

What are the tasks and functions of vitamin B12?

The most important tasks and functions of vitamin B12 include

  • Maintaining energy levels and vitality (energy production)
  • Production of red blood cells and prevention of anemia
  • Production and synthesis of DNA
  • Prevention of memory loss
  • Lightening the mood
  • Support the healthy functioning of the nervous system
  • Heart health
  • Good mobility
  • radiant skin
  • healthy skin, hair and nails
  • Support for digestion
  • Support for a healthy pregnancy
  • Prevention of cancer
  • Strengthening the bones
  • good eye health

What forms of vitamin B12 are there?

There are different forms of vitamin B12. They all contain the mineral cobalt, which is why compounds containing vitamin B12 are also called "cobalamins".

Forms of vitamin B12:

  • Cyanocobalamin
  • Hydroxycobalamin
  • Methylcobalamin
  • Adenosylcobalamin

The forms cyanocobalamin and hydroxycobalamin are absorbed and broken down by the body. This cleavage converts these two forms into the bioactive forms methylcobalamin and adenosylcobalamin . The active forms are directly involved in human metabolism.

Methylcobalamin is important for the production of the genetic material DNA and RNA. The form is mainly active in very active cells, such as blood cells. A deficiency leads to poorly functioning production of red blood cells.

Adenosylcobalamin acts in the mitochondria - the power plants of the cell. This form is therefore directly necessary for energy production. A deficiency leads to neurological and cognitive disorders. 

As methylcobalamin and adenosylcobalamin are the bioactive forms, it is recommended to take these two forms when supplementing in order to benefit from vitamin B12.

How is vitamin B12 absorbed by the body?

Some foods (especially animal products) contain vitamin B12. The vitamin binds to the protein molecules in these foods. During digestion, the vitamin is separated from the protein and released into the bloodstream. This process requires a sufficient amount of stomach acid. The substance intrinsic factor is necessary for smooth absorption into the bloodstream.

What is the intrinsic factor?

The intrinsic factor is needed to channel the vitamin B12 molecule through the intestinal mucosa. This makes it available to the body's cells. The intrinsic factor is therefore essential for vitamin B12 to be absorbed by the body. It is produced by the parietal cells of the stomach. A healthy stomach is able to produce sufficient intrinsic factor.

People who cannot absorb vitamin B12 properly may suffer from pernicious anemia. This is an anemia disorder in which those affected have a deficiency of intrinsic factor. A lack of intrinsic factor means that the vitamin B12 ingested through food cannot be properly absorbed.

There are two main reasons why too little or no intrinsic factor is produced and vitamin B12 can therefore not be sufficiently absorbed:

  • Hereditary absence of the intrinsic factor: e.g. no factor is produced due to a genetic mutation
  • Autoimmune diseases: antibodies prevent the production of the factor.

What happens if too little stomach acid is produced?

Too little stomach acid can result in a lack of intrinsic deficiency. However, as this is crucial for vitamin B12 absorption, this is another explanation as to why so many people do not absorb sufficient amounts of vitamin B12.

Which foods contain vitamin B12?

Vitamin B12 is found in some foods, especially in animal products:

  • Dairy products
  • Eggs
  • Meat
  • Fish
  • Poultry

Vitamin B12 is not normally found in plant-based foods. Nevertheless, there are some foods on the market that are additionally fortified with vitamin B12.

 

Who is affected by a defect?

The following groups of people are particularly affected by a shortage:

  • Long-time vegetarians and vegans
  • Persons aged 50 and over
  • People with stomach problems
  • People who have had operations on the gastrointestinal tract
  • People who take medication such as gastric acid inhibitors or metformin
  • Pregnant women
  • Infants

Vegetarians and vegans

Vitamin B12 is mainly found in animal foods. So if you eat mostly plant-based foods such as fruit, vegetables, beans and soy, you are at a higher risk of vitamin B12 deficiency. "Vegetarians who also consume eggs and dairy should eat products from one of these groups at least once a day," explains Stephanie Middleberg, registered dietitian at Middleberg Nuitrition in New York City. Vegans, who by definition do not consume any animal products, must take B12 supplements or consume specially fortified foods, such as breakfast cereals and grains. Dairy and meat substitutes are also often fortified with vitamin B12. Check the information on the packaging, as this does not apply to all foods.

Are the vitamin B12 capsules from Herbano vegan?

Yes

Persons aged 50 and over

With increasing age, the stomach produces less and less stomach acid, which is essential for the absorption of vitamin B12, explains Middleberg. The US Center for Disease Control and Prevention estimates that one in 31 people over 50 has a vitamin B12 deficiency. "Seniors often have less appetite and therefore eat less. In addition, they often take medication (e.g. for heartburn), which also inhibits the formation of stomach acid," she explains. Some seniors lose the ability to absorb vitamin B12 from food altogether and have to cover their requirements with supplements or, in the case of severe deficiency symptoms, injections.

People with stomach problems

People with gastric diseases or diseases of the small intestine may not be able to absorb enough vitamin B12 from food to maintain a healthy B12 level in the body. Examples of such a condition are coeliac disease or Crohn's disease. Mild impairment of cognitive function due to the onset of vitamin B12 deficiency may be the only sign of these digestive problems, which are usually followed by megaloblastic anemia and dementia.

People who have had operations on the gastrointestinal tract

Surgery on the digestive tract, for example to lose weight or to remove part or all of the stomach, often leads to a loss of cells that secrete gastric acid and the intrinsic factor. This reduces the amount of vitamin B12, especially from food, that the body releases and absorbs. Surgical removal of the distal ileum (part of the small intestine, also known as the small intestine) can also result in the body no longer being able to absorb vitamin B12. Patients who have to undergo these surgical procedures should be examined very carefully before and after the operation for signs of nutrient deficiency, including vitamin B12.

Pregnant women

Pregnant women in particular should pay attention to their vitamin B12 levels. Especially shortly before or after conception, there is a significantly higher risk of neural tube defects for the unborn child. Studies say that women who want to have children should eat foods rich in vitamin B12 in good time before pregnancy.

Infants

In infants, a B12 deficiency leads to serious complications: Anemia as well as movement and developmental disorders can even be fatal. Vitamin B12 deficiency is very rare in infants. It mainly affects children who are consistently fed a meat-free diet or who are breastfed by a mother who is vegan and does not take B12 supplements. Breast milk is the only source of nutrition for breastfed infants. Taking B12 supplements can reverse the process. This is the conclusion of a study published in the journal Pediatrics. To effectively prevent a deficiency, it is recommended to take vitamin supplements containing B12 during pregnancy.

How do you recognize a vitamin B12 deficiency?

Vitamin B12 is particularly important for the production of red blood cells and DNA, as well as for a healthy nervous system.

Unfortunately, symptoms only become noticeable after years of deficiency. The diagnosis is very complex, as the body can store vitamin B12 for three to five years. Symptoms therefore appear gradually and go almost unnoticed.

The first signs are

  • Tiredness
  • General weakness
  • Brain disorders (memory and concentration)

These symptoms are then followed by others, such as numbness or tingling in the arms and legs, depression, paranoia and even hallucinations. The signs of a deficiency are very varied. In addition, not every patient is equally affected, which makes diagnosis even more difficult. However, a complete avoidance of animal foods generally leads to deficiency symptoms more quickly.

Sometimes a B12 deficiency is confused with a folic acid deficiency. A low B12 level leads to a drop in folic acid levels. If you balance your folic acid levels in such a case, you are simply masking the B12 deficiency and not eliminating the underlying cause.

What are the symptoms of a vitamin B12 deficiency?

  • Pale, yellowish skin
  • Weakness and fatigue
  • Sensations of "formication"
  • Changes in mobility, poorer coordination
  • Glossitis and ulcers in the mouth
  • Dizziness and shortness of breath
  • Visual disturbances (optic neuropathy)
  • Mood swings and depression
  • Increased body temperature

1. pale and/or yellowish skin                     

People who suffer from a B12 deficiency often look pale. The skin and the whites of the eyes appear yellowish, as we know it from patients with jaundice. The lack of B12 causes problems with the production of red blood cells.

The vitamin plays a crucial role in the production of DNA, which is required for the formation of red blood cells. Without this DNA, the cells lack the necessary information and cannot divide.

This causes a form of anemia called megaloblastic anemia. As a result, red blood cells are formed in the bone marrow which are very large and fragile. These red blood cells are too large to pass from the spinal cord into the bloodstream. As a result, the proportion of red blood cells in the blood is reduced, which makes your skin appear pale. Because these blood cells are so fragile, many of them rupture and cause an excess of bilirubin in the body.

Bilirubin is the slightly reddish or brownish substance produced in the liver when it breaks down old red blood cells. High levels of bilirubin make the skin appear yellow.

2. weakness and fatigue

A vitamin B12 deficiency is often accompanied by weakness and tiredness.

This is also due to the lower proportion of red blood cells in the blood, which are responsible for transporting oxygen. This means that not enough oxygen reaches the body's cells. This is why you feel tired and weak.

In older people, this type of anemia is often caused by an autoimmune disease called pernicious anemia. Those affected do not produce enough of the very important protein intrinsic factor. This is essential to prevent vitamin B12 deficiency, as it binds the vitamin in the intestine so that the body can absorb it.

3. sensations of "ants running"

The more serious side effects of a long-term B12 deficiency include nerve damage. This occurs gradually, over time. Vitamin B12 plays a crucial role in the formation of myelin, a fatty substance. Myelin surrounds the nerves and forms a kind of protective sheath or insulation. Without B12, myelin is formed in a different way, which affects the function of the nervous system: it can no longer work as intended.

A common sign of this is paraesthesia, or sensations of "ants running", which can be compared to tingling in the hands and feet.

Interestingly, neurological symptoms usually occur together with anemia. However, 28 percent of the participants in one study showed neurological symptoms of B12 deficiency without showing signs of anemia at the same time.

Nevertheless, the occurrence of sensations of "formication" can have a variety of causes and does not necessarily indicate a B12 deficiency.

4. changes in mobility

An untreated deficiency damages the nervous system and affects the way you walk and move. These changes can also affect your balance and coordination, making you more susceptible to falls.

This symptom mainly occurs in older people aged 60 and over who suffer from an untreated B12 deficiency. Preventing or treating a deficiency can improve mobility in this age group.

But even younger people with a severe, untreated deficiency experience restrictions in their mobility.

5. glossitis and ulcers in the mouth

Glossitis is the medical term for inflammation of the tongue. This manifests itself in changes to the color and shape of the tongue, which swells red and is very painful. The inflammation can also smooth the tongue. Normally there are tiny bumps on the tongue on which the taste buds sit. These smooth out and disappear.

An inflamed tongue is very painful and can also affect the way you eat and speak.

Studies show that a swollen and inflamed tongue with long straight lesions is an early sign of a vitamin B12 deficiency.

In addition, some patients develop further symptoms in the mouth area: ulcers, tingling ("formication") on the tongue or a burning sensation or itching in the mouth.

6. dizziness and shortness of breath

If anemia occurs due to a lack of B12, you will notice this in the form of shortness of breath and slight dizziness, especially under stress.

This is caused by a lack of red blood cells, which cannot transport enough oxygen to the various cells in the body.

However, these symptoms may also be due to other causes. Therefore, if you experience unusual shortness of breath, you should consult a doctor to determine the cause.

7. visual disturbances (optic neuropathy)

One symptom of a B12 deficiency is visual disturbances or blurred vision.

This occurs when damage to the nervous system (caused by a lack of B12) affects nerves that lead to the eye. The damage can interrupt nerve signals that run from the eye to the brain. This affects your ability to see. This condition is called optic neuropathy.

These serious effects can often be reversed if sufficient B12 is supplied.

8. mood swings

Patients with a vitamin B12 deficiency often report changes in mood. Low B12 levels have been linked to brain disorders such as depression or dementia.

Scientists explain the connection with a theory called the "homocysteine hypothesis for depression".

This states that a high homocysteine level can damage brain tissue due to insufficient B12 and thus impede signals to and from the brain. This leads to mood swings.

In some studies, taking B12 supplements was able to reverse the symptoms.

Changes in mood and illnesses such as dementia or depression can have a variety of causes. The effects of supplements on these illnesses are therefore unclear.

However, if you have a deficiency, taking food supplements can lift your mood. However, they are not a suitable remedy or alternative to proven therapies for the treatment of depression or dementia.

9. increased body temperature

Very rarely, a vitamin B12 deficiency is accompanied by a high body temperature. The cause of this is not known. However, some doctors report that the body temperature normalized after a low B12 level was compensated.

Please note, however, that the cause of fever is usually an illness and not caused by a B12 deficiency.

Vitamin B12 deficiency occurs frequently and manifests itself in different ways. This makes a reliable diagnosis extremely difficult.

What causes a vitamin B12 deficiency?

  • Diet
  • Medication
  • Digestive disorders
  • Inflammations
  • Autoimmune diseases
  • Missing intrinsic factor

 

Diet

There are many different diets. A vegetarian and vegan diet very often leads to a deficiency, as non-animal foods contain very little to no vitamin B12.

Medication for heartburn can cause a vitamin B12 deficiency

Some heartburn medications suppress the production of stomach acid, which is needed to absorb vitamin B12. A 2013 study published in the Journal of the American Medical Association supports this statement. Researchers found that taking proton pump inhibitors (such as Prilosec and Nexium) for more than two years was associated with a 65 percent increased risk of vitamin B12 deficiency. Taking H2 receptor blockers (such as Pepcid and Zantac) for two years (or longer) is suspected to increase the risk of B12 deficiency by 25 percent. If you take such medications regularly, talk to your doctor about how you can protect yourself.

Taking the contraceptive pill makes you susceptible to a vitamin B12 deficiency

"Women who take oral contraceptives over a long period of time develop difficulties absorbing vitamin B12," explains Middleberg. "Studies show that tablets with a higher proportion of oestrogen increase the risk of B12 and folate (folic acid or vitamin B6) deficiency. This leads to the assumption that the oestrogen contained in the contraceptive pill is the cause of malabsorption of these nutrients." If you are taking the pill, talk to your doctor about the risks and whether you should take a B12 supplement to be on the safe side.

Digestive disorders lead to a deficiency

According to Middleberg, people with digestive disorders and impaired intestinal flora are at a higher risk of developing a vitamin B12 deficiency than others. Impairments of the digestive tract also hinder the absorption of nutrients from food. She says: "People with digestive disorders such as colitis, Crohn's disease, inflammatory bowel disease and leaky gut syndrome have a higher risk." Patients with coeliac disease usually cannot absorb the vitamin properly. If you suffer from one of these conditions, please speak to your doctor about B12 supplements or B12 injections, as you will not be able to meet your requirements for this important vitamin through food - no matter how much you eat. Your digestive tract cannot absorb the nutrients.

B12 deficiency often occurs after weight loss

"Some surgical procedures on the digestive tract, for example a gastric bypass, lead to poorer absorption of B12," explains Moon. This is due to:

  • The body's reduced ability to digest food
  • Formation of too little intrinsic factor

This protein is essential for the body to be able to absorb B12. These impairments usually last a lifetime. People with gastric bypass therefore often have to take B12 supplements for the rest of their lives if they do not want to risk a deficiency.

Bacterial overgrowth of the small intestine

Bacterial overgrowth of the small intestine is a disease in which normal bacteria from the large intestine also colonize the small intestine. This creates "chaos" in the digestive tract, which is accompanied by gas, bloating and diarrhea, constipation, heartburn, weight loss and nausea. A lesser-known side effect of overgrowth in the small intestine is vitamin B12 deficiency. This occurs because certain strains of bacteria in the intestine require vitamin B12. If too many or too large strains of these bacteria have colonized the small intestine, they consume the available vitamin B12 before it can be absorbed by the body.

If you suffer from an unexplained vitamin B12 deficiency, have this checked for overgrowth in the small intestine.

Inflammations

Inflammation of the colon, also known as ileitis, can have a variety of causes. These include inflammatory bowel disease (Crohn's disease), various infections, taking too many pain-reducing NSAID medications, etc. Regardless of the exact cause, ileitis always impairs vitamin B12 absorption and thus causes a deficiency. Ileitis is usually, but not always, accompanied by pain in the lower right abdomen and/or diarrhea. These symptoms should definitely be discussed with a doctor.

Autoimmune diseases

Vitamin B12 is mainly absorbed in the last part of the small intestine (in the colon). However, the digestion process begins in the stomach. The stomach wall is lined with special cells. Only when these cells are working properly can sufficient vitamin B12 be absorbed by the body. Stomach acid-producing cells must keep the pH low enough so that the vitamin can be separated from the protein molecules of the food to which it is bound. Still other cells form a compound called intrinsic factor, which also plays an important role in the absorption of vitamin B12.

Autoimmune diseases can destroy these specialized cells and thus impair the body's ability to absorb vitamin B12 from food. Such autoimmune diseases include atrophic gastritis and pernicious anemia. With a simple blood test, your doctor can determine whether these diseases are responsible for an unexplained vitamin B12 deficiency.

How much vitamin B12 do we need?

The need for vitamin B12 depends on many factors, such as age, eating habits, previous illnesses, medication taken or similar.

The average daily requirement in micrograms (µg) by age:

Infants

0 to 3 months

 0.4_µg   

4 to 11 months

 0.8_µg

Children

1 to 3 years

 1.0_µg

4 to 6 years

 1.5_µg

7 to 9 years

 1.8_µg

10 to 12 years  

 2.0_µg

13 to 14 years

 3.0_µg

Teenagers + adults   

From 15 years

 3.0_µg

Pregnant women

 

 3.5_µg

Breastfeeding

 

 4.0_µg

 

The DGE 's recommended daily requirement is a guideline to prevent vitamin B12 deficiency in otherwise healthy people. It is therefore important to know whether the body can absorb vitamin B12 at all. For example, if there is too little intrinsic factor, only little vitamin B12 can be absorbed, which can lead to a deficiency despite sufficient vitamin B12 intake.

How can the vitamin B12 level be measured?

The vitamin B12 level can be tested either at the doctor's or practically at home or by means of a self-test.

The vitamin B12 urine test (available from Herbano for Germany and Austria) is a quick and easy way to test your vitamin B12 level at home without having to wait a long time at the doctor. This self-test measures the level of methylmalonic acid in the urine. An elevated level is an indirect marker for a vitamin B12 deficiency.

 

How is a vitamin B12 deficiency treated?

A vitamin B12 deficiency can be remedied by taking high doses of vitamin B12. Risk groups in particular should prevent a deficiency in good time by taking vitamin B12.

In severe cases (such as pernicious anemia), injections are even administered and then usually switched to high-dose supplements. Talk to your naturopath.

For most people, a deficiency can be corrected with this measure. However, please note that any nerve damage that has already occurred due to the deficiency could be permanent.

How can a vitamin B12 deficiency be avoided?

  • For many people, a vitamin B12 deficiency can be avoided by paying attention to a diet in which mainly animalfoods with a high vitamin B12 content are consumed.
  • With a strict vegetarian or vegan diet, it is essential to consume plenty of bread, cereals or other cereal products that have been fortified with vitamin B12, or to use an appropriate supplement. Regular consumption of fortified foods can prevent a deficiency. However, depending on lifestyle and medical conditions, a deficiency can still occur.
  • From the age of 50 and especially for seniors, the Institute of Medicine recommends an extra dose of B12 in the form of a supplement, as the body's ability to absorb the vitamin from food decreases from this age.
  • If you are taking medication that impairs the absorption of vitamin B12, you may need to take a supplement. Talk to your naturopath
  • People with stomach problems or who have undergone gastrointestinal surgery should also have their vitamin B12 deficiency checked.

What side effects can occur when taking vitamin B12?

Vitamin B12 is generally considered safe. As with many vitamins, overdoses or interactions can lead to side effects.

Possible side effects are

  • Headache
  • Itching
  • Swelling
  • Nervousness and anxiety
  • involuntary and uncontrollable movements

Take special care with:

  • Pregnancy and breastfeeding: Vitamin B12 can usually be taken safely during pregnancy or while breastfeeding. Only use oral preparations and adhere to the specified dosage. It is best to clarify your dosage requirements with a naturopath.
  • After a surgical stent insertion: After a stent insertion, you should not take a preparation containing the combination of vitamin B12, folic acid and vitamin B6. This combination can increase the risk of narrowing blood vessels.
  • Allergic reactions or sensitivity to cobalt or cobalamin: Do not take vitamin B12 if you suffer from this allergy.
  • Leber's optic atrophy, a hereditary eye disease: Do not take vitamin B12 if you suffer from this disease. Taking it can lead to serious damage to the optic nerve and, in the worst case, to blindness.
  • Abnormal red blood cells (megaloblastic anemia): Megaloblastic anemia is sometimes treated with vitamin B12. However, this can lead to serious side effects. Therefore, do not take vitamin B12 on your own, but only on the instructions and under the supervision of your doctor.
  • High red blood cell count (polycythemia vera): Treating a vitamin B12 deficiency can unmask the symptoms of polycythemia vera.

Intake of vitamin B12 with:

  • Metformin: Taking this diabetes medication can cause the body to absorb less vitamin B12.
  • Vitamin C (ascorbic acid) Taking vitamin B12 together with vitamin C may result in less vitamin B12 being available in the body. To avoid this interaction, you should take vitamin C two or more hours after taking vitamin B12.
  • Proton pump inhibitors: Taking omeprazole (Prilosec), lansoprazole (Prevacid) or other gastric acid inhibitors can impair the absorption of vitamin B12.
  • Aminosalicylic acid: In the past, this drug was often used to treat digestive problems. Taking it can reduce the body's ability to absorb vitamin B12.
  • Colchicine (Colcyrs, Mitigare): Taking this anti-inflammatory drug to treat and prevent gout attacks can also reduce the absorption of vitamin B12 in the body.
  • Chloramphenicol interacts with vitamin B12: Vitamin B12 is important for the formation of new blood cells. Chloramphenicol can reduce the number of new blood cells. Long-term use of chloramphenicol can reduce the effect of vitamin B12 on the formation of new blood cells. However, most people only take chloramphenicol for a short period of time, so this interaction is not normally a major problem.
  • Alcohol: Alcohol consumption depletes the body's vitamin B stores, especially if you drink large amounts of alcohol. You should therefore limit or completely stop your alcohol consumption if you are taking vitamin B12 supplements.

 

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