Vitamin B12 deficiency – symptoms and treatment

Why do we need Vitamin B12 and what are the consequences of a deficiency?

Vitamin B12 (Cobalamin) is an essential water-soluble Vitamin that can produced by the human body. So he is dependent on a constant supply via food.

Table of contents

The three forms

The Vitamin works in the human body in three forms:

  • Methylcobalamin acts in the cell plasma,
  • Adenosylcobalamin in the mitochondria (power plants of cells),
  • and Hydroxocobalamin works both in the blood as well as in the cell plasma.

Methylcobalamin and Adenosylcobalamin are Both so-called “bioactive Coenzyme”. The body can use the Vitamin only in these two forms directly. The third in the League, the Hydroxocobalamin is not a coenzyme, but, above all, as a toxin and free radical scavenger.

Vitamin B12 plays an important role in many processes in our organism. According to far-reaching can be the consequences of a defect. (Image: Mikhail Petrov/


Vitamin B12 has the most varied of tasks in the human organism. The Cobalamin is involved in the energy metabolism, blood formation, DNA synthesis, folic acid metabolism, the degradation of homocysteine, the production of the myelin sheath (nerve sheath; the nerve fibers) and some neurotransmitters isolated.

Cell division, blood formation, DNA synthesis

The best known effect of Vitamin B12 on the formation of blood. There is a pronounced deficiency can lead to anemia. Thus, cell division can properly take place is the Cobalamin is equally important. In this process, also folic acid is involved. In the case of a lack of so-called transcription errors during DNA synthesis can occur, what is considered in the longer term, may lead to an increased risk of cancer. Also chronic diseases associated with it.

The formation of red blood cells, erythropoiesis, is the presence of the Vitamin. Otherwise, this can lead to a maturation disorder of the red blood cells. These are not in the position, the necessary amount of oxygen. Complaints such as weakness, dizziness, shortness of breath and hypotension suggest.

Energy metabolism

Advertising teaches us that a deficiency can lead to lack of energy. This B-Vitamin has an impact on the performance and energy level. Our organism requires for Everything he does, energy. For food is important. The resulting energy is stored and retrieved when needed. In this complicated process Vitamin B12 plays a major role.

Structure of the cell membrane

Vitamin B12 is involved in the formation of cell membrane lipids. This process, however, is not explored yet. The membrane-forming lipids, however, will be a component of the myelin sheaths. These act as a protective sheath around the nerves, comparable to that of the insulating layer of the electric cable. Missing cases this protection, which can be caused by a Vitamin B12 deficiency, suffering the patient is experiencing tingling, muscle weakness, paralysis, incoordination, or memory disorders. In turn, it should also have a regenerating effect on the nervous.

Nitrosativer Stress

Nitrosativer Stress is a kind of oxidative Stress. However, the oxygen radicals are not Evil, but the nitric oxide radical (NO). Too many of them strain the body and can damage it. Nitrosativer Stress is caused by inflammation, chemicals, drugs, nicotine, mental and physical Stress. In a normal, balanced amount of NO is important. As the vessel relaxes this, for example, the interior walls, which has a positive effect on a high blood pressure. Vitamin B12, in the Form of Hydroxocobalamin can prevail against many of the nitric oxide radical, and makes NO harmless. Thus, the so-called nitrosativer Stress is to be tackled.


Homocysteine is produced during protein metabolism in the degradation of the essential amino acid methionine (from proteins in the food). Homocysteine is oxidized in the blood, and attacks as a result, the inside of the blood vessels, which can, over time, to a hardening of the arteries and later lead to a heart attack. Vitamin B6, B12 and folic acid can break down dangerous homocysteine.

Vitamin B12 impulses is of fundamental importance for the functioning of the nerves and the Transmission of nerve. (Photo: adimas/

Synthesis of neurotransmitters

Neurotransmitters neurotransmitters needed for Transmission of nerve impulses. It is essential for the synthesis of various messenger substances such as Serotonin, dopamine, epinephrine, norepinephrine, and acetylcholine.

What is Cobalamin can do everything

Cobalamin ensures that there is sufficient energy and thus acts against fatigue. The Vitamin supports the growth of the nerve that is involved in the production of red blood cells, ensures healthy cell division, protects the blood vessels, is important for concentration, good memory and mental energy and has a positive effect on our mood. For Pregnant women, and also for the successful conception of a presence of Vitamin B12 in addition to folic acid is essential.

Interaction of Vitamin B12 and folic acid

Vitamin B12 and folic acid (folate or Vitamin B9) work together in the body closely. So the Two, as already mentioned, are involved massively in the removal of harmful homocysteine. Cobalamin is needed to activate folate (this is the natural, bioactive Form of folic acid). This means that you can develop from a Vitamin B12 deficiency is a functional deficiency of folic acid.

The Vitamin in the food

The folate from food is bound in the human organism in the stomach called Intrinsic Factor. This will be transported in the terminal Ileum (last section of the small intestine), where the Cobalamin to the blood circulation is delivered.

Causes: What can interfere with the absorption of Vitamin B12

Among the causes for impaired absorption of Vitamin B12, an inflammation of the stomach mucosa, a removal of Parts of the stomach, a so-called TYPE A Gastritis ( an autoimmune disease in which the body attacks its own stomach, and thus also of the Intrinsic factor can no longer be properly formed), atrophic Gastritis (atrophic mucosal changes, decrease in the enzyme and hydrochloric acid production), drugs (for example, stomach acid blockers) and chronic inflammation of the bowels, or distances of parts of the Intestine.

In the case of a celiac disease, caused by intolerance to gluten, suffering, Affected, often under a Vitamin B12 deficiency. (Image: J. Mühlbauer exclus./

The Vitamin B12 Deficiency

In addition to the above-mentioned causes can be a Vitamin B12 deficiency is based, there are still More. These include:

  • a low dietary intakes, for example through a strict vegetarian or vegan diet;
  • a Malabsorption of the Vitamin cannot be absorbed from the intestine, as is, for example, in the case of celiac disease and exocrine pancreatic insufficiency in the case;
  • heavy alcohol consumption,
  • infestation with the Fish tapeworm,
  • an Overgrowth of the intestine,
  • an increased need (for example, in the context of an infection or during pregnancy),
  • Displacement due to B12-analogues (for example Spirulina),
  • high age
  • or the genetically-related “Imerslund-Gräsbeck-syndrome”.

Symptoms Of Vitamin Deficiency

The liver can store folic acid for up to three years. Therefore, vitamin deficiency symptoms usually occur only after several years of persistent under-supply. To fatigue, exhaustion and pallor, caused by the pernicious anemia (Vitamin B12 deficiency anemia).

The deficiency also affects the nervous activity. Thus, symptoms, such as paresthesia of the hands and feet, tingling, paralysis, and declining mental skills. A well-known indication of the lack of situation, a smooth red tongue, with burning sensation of the Tongue and lesions of the oral mucosa. More symptoms of immune deficiency, bleeding tendencies, loss of appetite and weight loss.

Vitamin B12 is found in high concentrations especially in meat and some other animal products. (Image: bit24/

Daily usage of B12 in the diet

The daily consumption of an adult of Vitamin B12 is about 3 micrograms (micrograms). In pregnancy and lactation it increases to 3.5 to 4 ág. Especially in the human liver, approximately 2000 to 4000 µg are stored. In the case of a supply is reduced.

Vitamin B12 is almost exclusively found in animal products such as meat, sausage, fish, dairy products and eggs. Exceptions of non-animal origin, with a very low concentration of Sauerkraut, sea buckthorn and Shitake. For the daily requirement of 100 g Emmental cheese, 70 g, for example beef, 100 g of salmon, or 60 g of minced meat. Here, it is already clear that strict vegetarians and especially Vegans may develop Vitamin B12 deficiency.

Such a deficiency is detected

The symptoms listed above usually lead to a doctor. This is the arrange on the basis of a detailed medical history, a blood test and a urine test. The diet will be discussed, may be reconsidered and changed.

A diet-related deficiency must be differentiated from an absorption-related deficiencies. A special investigation is necessary. In principle, the determination of the cause of the subsequent treatment is important. For any parenteral intake in the Form of syringes or infusions, for example, is necessary. Thus, initially, the body doses shall be replenished. Thereafter, a maintenance treatment follows, often in the Form of tablets. A not-so-serious deficiency can even be through oral Substitution offset.

With a blood test of the present Vitamin-B12-deficiency is relatively easy to determine. (Image: jarun011/

Important for oral therapy, the type of the Cobalamins, which is included in the tablets. To recommend supplements that contain Methylcobalamin, Hydroxocobalamin, and adenosylcobalamin. These three species are also found in natural foods and are needed in the body for different tasks.


Folate is an essential, a vital Vitamin and is part of the B-vitamins, which are important for nerve, brain and Fitness responsible. A deficiency can be quite trigger far-reaching complaints and or eliminated treated. Here is a diagnosis of the underlying disease is essential. Persons living over extended periods of time in a strictly vegetarian or vegan, run the risk of a such Cobalamin to develop deficiency. Here is may think of a daily Substitution with a suitable preparation. (sw)