Vitamin B12 or cobalamin

Vitamin B12, also known as cobalamin, is a vitamin of the B group, so it is water soluble. It is a very important vitamin for the functioning of the brain, the nervous system and in DNA synthesis. This vitamin must be provided through food, the populations most at risk of deficiency are vegans and the elderly due to their low consumption of food of animal origin.

Characteristics of vitamin B12 :

  • Present in animal products
  • Essential for a healthy nervous system
  • Its deficiency can induce anemia
  • Additional charge required in case of vegan diet

Why eat foods rich in vitamin B12?

What is the purpose of vitamin B12?

Role in hematopoiesis

Vitamin B12 has an anti-anemic role, it also helps in the assimilation of folic acid (vitamin B9).

Maintenance of the nervous system

It is particularly in the myelin sheath that vitamin B12 plays a role in helping to protect nerve cells.

Anti-allergic role

Combined with an antihistamine, vitamin B12 can have a beneficial role in the disappearance of allergic symptoms. In addition, it is also detoxifying and helps the body to purge itself of toxins accumulated in the liver.

Vitamin B12 and cancer

To date, a few scientific studies have highlighted the detoxifying role of vitamin B12 following certain chemotherapies.

Where is vitamin B12 found? 20 foods rich in vitamin B12

Vitamin B12 is found mainly in foods of animal origin since animal feed is itself supplemented with B12. No animal or plant is able to synthesize B12, only certain bacteria are able to do so. Here are 20 foods to find the right amount of vitamin B12.

Foodstuffs Serving size Amount of vitamin B12 (μg)
Beef liver 100g 65
Veal liver 100g 60
Lamb liver 100g 35
Caviar 100g 16
Oysters 100g 14,5
Liver pâté 100g 13,5
Rabbit 100g 10
Liver dumplings 100g 10
Mackerel 100g 9
Herring 100g 8,5
Moulds 100g 8,5
Beef 100g 5
Wild boar 100g 5
Trout 100g 4,5
Tuna 100g 4,3
Goose 100g 4
Wild salmon 100g 3,5
Camembert 100g 3,1
Emmental cheese 100g 3,1

How to use vitamin B12 properly

Use of vitamin B12

The ANSES recommends a daily intake of 2.4 μg of vitamin B12 for a healthy adult.

Vitamin B12 supplement in case of a vegan diet

It is recommended to take vitamin B12 supplementation for populations on a vegan diet or consuming very little food of animal origin. Whatever the form (tablet, ampoule, injection…), vitamin B12 is absorbed in the same way by the body.

When this vitamin B12 is consumed as a dietary supplement, the dosage can go up to 5000 μg, which is far from the recommended daily dose of 2.4μg This can be explained by the storage of vitamin B12 in the body, which allows certain food supplements to be taken monthly and not daily. At the same time, the vitamin B12 contained in a tablet is not totally absorbed by the body, so it will be necessary to take a highly dosed supplement to cover its needs. To find out which vitamin B12 to choose for you, please ask your doctor for advice.

In some special cases, vitamin B12 may be administered as an injection. For example, in case of severe malabsorption or following digestive surgery. However, vitamin B12 by injection can cause some undesirable side effects: pruritus, urticaria, eczema, etc.

Adverse effects of cobalamin (vitamin B12)

Vitamin B12 deficiency

A wide range of symptoms can occur in cases of vitamin B12 deficiency, the most common of which are neurological symptoms (tingling, pain), anemia (low iron levels in the blood) and digestive disorders (constipation, diarrhea). Vitamin B12, in case of deficiency, can also cause more general symptoms such as hair loss, pallor, etc. In case of doubt, please contact your doctor. He will be able to explain how to treat vitamin B12 deficiency if necessary and according to your case.

Too much vitamin B12 in the blood, what symptoms?

It is very rare to provide too much vitamin B12 to your body, to date the only side effect noticed in case of excessive consumption of B12 is an acne outbreak, no real toxicity has been demonstrated.

Interactions of vitamin B12 with other elements

Many nutrients have a positive effect on the metabolism of vitamin B12, and vice versa. For example, vitamin B9 needs vitamin B12 to be activated, so a deficiency of vitamin B12 often leads to a concomitant deficiency of vitamin B9.

In addition, vitamin B12 needs vitamin B7 and magnesium to be bio-activated.

Finally, vitamins B2 and B3 as well as calcium are essential for the metabolism of vitamin B12. It may then be advisable to take a multi-vitamin complex in addition to vitamin B12 and in case of deficiency.

Chemical properties

Vitamin B12 or cobalamin is a water-soluble vitamin of the B group. Its crude chemical formula is C72H100CoN18O17P and its molecular weight 1579, 5818 g/mol. This vitamin is directly involved in the proper functioning of the nervous system and in the production of DNA.

Vitamin B12 exists in 8 distinct forms, all derived from cobalamins. Cobalamin has a structure similar to that of heme. However, the central iron atom is replaced by a cobalt atom.

History of the event

History of the nutrient

It was in the 1800s that scientific research focused on vitamin B12. Indeed, the deadly pernicious anemia pushes the scientific community to take an interest in this vitamin. The role of vitamin B12 in anemia and red blood cell synthesis was discovered shortly afterwards.

In 1948, Dorothy Hodgkin identified the three-dimensional configuration of vitamin B12.

It was only in 2007 that the study of the synthesis of vitamin B12 by microorganisms was completed.