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Vitamin B12
Last reviewed: 05.07.2025
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Vitamin B12 is very important for our body, because the harmonious consumption of vitamins helps to look good. The word "vitamin" comes from the Latin "vita" - that is, life. The absence of at least one vitamin in the human body causes all sorts of failures and disorders. Vitamin B12 is no exception, and its role is also very important.
General knowledge about vitamin B12
Other names for this vitamin include cobalamin, antianemic vitamin, and cyanocobalamin.
Why is vitamin B12 called "antianemic"? The fact is that the discovery of this vitamin was a real breakthrough in science and medicine. Thanks to the effect of this vitamin, the hematopoietic function of the body of people suffering from anemia returns to normal. Even one millionth of a gram of this vitamin helps to improve the general condition of the patient. In the human body, a little cobalamin is produced with the help of intestinal microflora, and the rest comes with animal food.
This vitamin is considered water-soluble, but a small supply of it can be stored in the liver, provided that it is completely healthy.
Daily requirement of vitamin B12
To ensure that your body does not fail, you only need to consume up to 3 mcg of vitamin B12 per day. There is no specific limit to its quantity, since the maximum permissible level of this vitamin has not been determined.
Conditions under which the need for vitamin B12 increases
As with any other vitamin, the need for vitamin B12 increases with excessive physical activity, pregnancy and breastfeeding. As well as with smoking and drinking alcohol in high doses.
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Vitamin B12 absorption
The protein mucoprotein contained in the gastric juice (also called the intrinsic factor of Castle) combines with vitamin B12 (is the extrinsic factor of Castle), and from this a complex protein is formed. Thus, vitamin B12 is freely absorbed by the walls of the stomach into the blood.
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The beneficial effects of vitamin B12
The main "concern" of vitamin B12 is the management of the blood formation function. Cobalamin stimulates the growth of the body, reduces the amount of cholesterol in the blood. Thanks to it, protein absorption occurs, liver cell fat metabolism occurs, and the peripheral and central nervous systems are maintained in a healthy state.
Interaction with other substances in the body
Vitamin B12 interacts well with vitamin B9 in the process of hematopoiesis, stimulation of growth and development of our body.
Signs of Vitamin B12 Deficiency in the Human Body
People with a clear deficiency of vitamin B12 may develop various ulcers in the mouth, they may feel a burning or tingling sensation in the tongue. The body of such people has an unpleasant odor. If a person is very tired, feels weak and suffers from headaches, then it is worth considering whether it is a deficiency of vitamin B12? With intense physical exertion, a person's heart rate may change dramatically and shortness of breath may appear. With a lack of this vitamin, appetite may disappear, the skin may turn yellow. Sometimes there is a feeling of "goosebumps on the skin" and heaviness when walking.
Signs of Vitamin B12 Excess
No evidence of cobalamin excess has been found in humans.
What influences the amount of vitamin B12 in foods?
The amount of cobalamin in food products cannot be affected by high temperatures, even after the product is boiled, the vitamin will not lose its properties. At room temperature, the vitamin also does not lose them. Only sunlight can reduce its activity.
Why might vitamin B12 deficiency occur?
A deficiency of cobalamin in the body may occur with diseases of the digestive system (gastritis, colitis, ulcers, during surgery to remove the stomach or intestines). If a person has helminths in the body, then the absorption of the vitamin may also be impaired. Liver disease and alcoholism do not allow cobalamin to be absorbed normally by the body, so in such cases it is taken in the form of injections.
Sometimes vegetarianism can have a negative effect on the body. People who eat only plant foods will definitely suffer from a lack of vitamin B12, and this will have a negative effect on their body. So be sensible, no prejudice is worth your health!
What foods contain vitamin B12?
You can replenish the amount of cobalamin in your body by eating rabbit, lamb, pork or beef - they contain 2 - 4.5 mcg of this vitamin. The liver of different animals contains vitamin B12 in different quantities: up to 60 mcg - beef, up to 30 mcg - pork and up to 16.58 mcg - chicken. If we talk about fish, then a large amount of cobalamin is contained in cod, mackerel, sardine, sea bass and carp - they all contain from 1 to 12 mcg of cobalamin.
Octopus and crab also contain vitamin B12, so the presence of these products in your daily diet will not hurt at all. Among milk products, Dutch cheese and sour cream contain a large amount of vitamin B12 (0.4-1.4 mcg). Let's not forget about chicken eggs. They are also very rich in vitamin B12 (up to 0.5 mcg).