Vitamin B12 or cobalamin is essential for many metabolic processes in the body. It is involved in blood formation and cell formation, and it also contributes significantly to healthy nerve function. However, the vitamin is found almost exclusively in animal foods. A vitamin B12 deficiency therefore threatens vegetarians and vegans in particular.
Vitamin B12: occurrence and deficiency
Vitamin B12 is absorbed through the small intestine. For this, the organism needs a special protein – the so-called intrinsic factor – which is produced in the stomach. If both components work together, animal products are good sources of vitamins. Among the types of meat, beef and pork as well as offal and liver are particularly rich in the vitamin. But fish such as tuna or salmon as well as mussels, dairy products and eggs also contain significant amounts of vitamin B12.
Due to the almost exclusive occurrence of cobalamin in animal foods,
Vitamin B12 deficiency in vegetarians and vegans most likely.
Symptoms of vitamin B12 deficiency
A vitamin B12 deficiency manifests itself, among other things, in anemia, which is accompanied by paleness, dizziness and exhaustion. Shortness of breath can also be a result of deficiency-related anemia.
Severe vitamin B12 deficiency can also result in symptoms such as tingling, loss of sensitivity in hands and feet, impaired reflexes, confusion and other neurological symptoms. Even changes in behavior such as depressive or aggressive behavior can be due to a vitamin B12 deficiency.
Causes of vitamin B12 deficiency
A vitamin B12 deficiency can occur in vegetarians and vegans, particularly due to insufficient
Ingestion arises from not using animal products.
Diet is not the only possible cause. Inadequate intake due to illness can also lead to a vitamin B12 deficiency. For example, disorders of the intestinal flora, inflammation of the small intestine, but also taking certain medications or the lack of intrinsic factors reduce absorption.
Certain liver diseases sometimes also mean that the body can only store small amounts of the vitamin. If there is no absorption, the organism is temporarily more susceptible to a deficiency. Vegetarians and vegans with liver disease are therefore particularly at risk.
Vitamin B12 deficiency in vegetarians
Since vegetarians generally still consume animal products – for example in the form of eggs or milk products – the risk of a vitamin B12 deficiency is rather moderate. If these foods are regularly included in your diet, you are adequately supplied – as long as they do not have a disturbed absorption or storage function.
A varied and balanced diet also ensures a sufficient supply of vitamin B12 for vegetarians.
Vitamin B12 deficiency in vegans
Unlike vegetarians, vegans have no animal products in their diet. As a result, they lack the main source of vitamin B12. However, there are some plant foods that contain the vitamin. It is found in high concentrations in microalgae such as chlorella and in the nori algae, which are mainly known from Japanese cuisine.
At 206 or 32 to 78 micrograms per 100 grams of food, the content of these plants is significantly higher than that of animal sources, which are 0.4 – 39 micrograms. However, it has not yet been clarified how well the organism can utilize vitamin B12 from plant sources. Whether they prevent a shortage is therefore not certain.
Prevent vitamin B12 deficiency
If the diet of vegans and vegetarians does not provide enough vitamin B12, it can be easily supplemented with a dietary supplement. Older people, whose absorption into the organism is often reduced, also benefit from these preparations. In addition, there are now various grain products that are enriched with the vitamin. Typically, an intake of 3 micrograms from fortified foods or 10 micrograms from a dietary supplement is recommended. However, it is best to talk to your (general) doctor in advance to determine the exact dose for you.
Anyone who suspects symptoms of a vitamin B12 deficiency should have their vitamin level in their blood checked by a doctor. If the intake is not sufficient for vegetarians through a targeted diet or through a dietary supplement, the vitamin can also be injected in high doses.
During and following the vitamin cure, the level should also be checked at regular intervals. In this way, another vitamin B12 deficiency with clear symptoms can be avoided.
UGB, association for independent health advice. (nd). Vitamin B12 – B12 deficiency – vitamin deficiency – vegan nutrition – vegetarian nutrition – cobalamin – vitamin supply – risk groups vitamin deficiency – sources of vitamin B12 – bioavailability – UGB health advice. UGB. Retrieved September 8, 2022, from https://www.ugb.de/ernaehrungsberatung/vitamin-b12-manchmal- wird-es-knapp/?cobalamin-vitamin-b12 Johnson, LE (nd). Vitamin B12 deficiency. MSD Manual Edition for Patients. Retrieved September 8, 2022, from https://www.msdmanuals.com/de-de/heim/ern%C3%A4hrungsst%C3%B6rungen/vitamin/vitamin-b12-lack UGB, association for independent health advice. (nd). Vitamin B12 – B12 deficiency – vitamin deficiency – vegan nutrition – vegetarian nutrition – cobalamin – vitamin supply – risk groups vitamin deficiency – sources of vitamin B12 – bioavailability – UGB health advice. UGB. Retrieved September 8, 2022, from https://www.ugb.de/ernaehrungsberatung/vitamin-b12-manchmal- wird-es-knapp/?cobalamin-vitamin-b12
