Vitamin B12 deficiency


Vitamin B12 is a very important and vital vitamin for the body. It is needed in well over 100 different processes in the body and is therefore essential for the body’s functioning. Since vitamin B12 is contained particularly in animal products, a vitamin B12 deficiency is a topic, which concerns vegetarians and Veganer substantially.

In addition, different illnesses of the digestive tract, with which the Vitamin cannot be excluded sufficiently from the food mash any longer, play a crucial role. Vitamin B12 (also called “cobalamin”) is stored in the healthy liver for about 2-3 years, and the daily dose of about 2 micrograms (i.e. 2 millionths of a gram) is easily balanced for just this period. However, various diseases can lead to a number of symptoms, which will be discussed in more detail below.


A vitamin B12 deficiency brings with it a wide range of symptoms, which can be roughly divided into three categories: Internistic symptoms, neurological symptoms and psychiatric symptoms. Internistic symptoms are symptoms that affect the body’s internal organs. Since vitamin B12 is needed for the formation of red blood cells, a so-called vitamin B12 deficiency anemia, i.e. vitamin B12-induced anemia, occurs in the course of the disease.

The lack of red blood cells leads to the remaining blood cells being “stuffed” with too much hemoglobin and swelling. This makes them less mobile and makes it less easy for them to pass through the fine, permeable wall layer of the blood vessels. The swelling of the erythrocytes is medically called macrocytic anemia.

Similar to iron deficiency, this is characterized by fatigue, listlessness and lack of drive – all unfortunately quite unspecific symptoms, which is why the disease is often not recognized for a long time. Since, in addition to blood formation, DNA and cell formation also function less well, immunological symptoms are also increasingly in the foreground, such as the increased occurrence of common diseases like a cold or increased susceptibility to infections. Further symptoms can be high blood pressure, allergies, headaches, lack of concentration, torn corners of the mouth (so-called rhagades) and increased occurrence of aphthae and inflammations of the oral mucosa (see: Red spots on the tongue).

The latter can be explained by the reduced rate of cell formation associated with a B12 deficiency: the oral mucosa and skin are strongly proliferating organs, i.e. they are always in a state of remodeling – a cell deficiency becomes particularly noticeable here. In advanced, severe stages, the symptoms of B12 deficiency range from heart attack, cerebral infarction, muscle tremors, impaired vision, incontinence, dizziness and insecure gait to fainting. Can a vitamin B12 deficiency lead to diarrhoea?

You can find out everything about this topic at: Diarrhoea caused by vitamin B12In addition to the internal symptoms, a number of neurological symptoms also occur. This is due to the fact that vitamin B12 is needed for the formation of the so-called myelin sheath of the nerves. The myelin sheath is virtually the sheathing of the nerves, similar to the rubber layer that insulates power cables.

Without this insulating layer, signals can be passed on more poorly or not at all. Neurological symptoms often occur before physical symptoms: For example, there can be a lack of sensation with a disturbance of viral sensation, which continues with an impairment of depth sensitivity (symptomatically through “tingling” in the limbs) and can end in advanced stages in paralysis, since the muscles are also supplied by nerves. Furthermore, the risk of developing Alzheimer’s dementia and other neurodegenerative diseases is increased.

The symptoms of vitamin B12 deficiency can be masked by an overdose of folic acid.

Psychiatric symptoms form a smooth transition to the neurological ones and express themselves in the form of hallucinations, psychoses and confusion. Panic attacks and anxiety can also occur.

Since vitamin B12 deficiency affects a very elementary level of body function, the possible effects and manifestations vary greatly. The deeper the disorder, the more varied the symptoms. This is also the case with B12 deficiency, which often makes rapid diagnosis and treatment difficult.

Often it is only the combination of several symptoms that provides the decisive clue in the right direction. The symptoms of vitamin B12 deficiency can be masked by an overdose of folic acid.