Vitamin B12 - In Foods, Symptoms Of Deficiency And Excess

2024 Author: Rachel Wainwright | [email protected]. Last modified: 2023-12-15 07:39

Vitamin B12

Vitamin B12 is a water-soluble B vitamin. Unlike other substances in this group, it can accumulate in the human body, most of all in the liver, spleen, lungs and kidneys. It is absorbed in the small intestine and deposited in the liver.

It contains a cobalt ion, hence the other name - cyanocobalamin, or cobalamin. Cyanocobalamin is resistant to light and heat, and is better preserved in food when cooked.

Vitamin B12 content in foods

The activity of cyanocobalamin is very high and the amount of vitamin B12 in foods is measured in μg. Accordingly, a person's need for it is small.

The amount of vitamin B12 in foods (μg / 100g):

• Beef liver - 60;
• Heart - 25;
• Oysters - 18;
• Trout - 7.5;
• Herring - 13;
• Russian cheese - 1.5;
• Sardines in oil - 8.5;
• Rabbit meat - 4.3;
• Beef - 3.0;
• Sea bass - 2.4;
• Cod - 1.6;
• Dutch cheese - 1.1;
• Poshekhonsky cheese - 1.4;
• Cottage cheese - 1.0;
• Chicken egg - 0.5;
• Cow's milk - 0.4;
• Kefir - 0.4;
• Butter - 0.1.

The main source of this vitamin for the body is animal products. A little cobalamin is synthesized in the intestines by its own microflora. Very small amounts are found in soybeans, hops, tops, spinach, green salad.

Vitamin B12 intake

Age determines the daily requirement for cyanocobalamin. So, in infants up to 6 months, it is 0.4 μg / day, in children from 6 to 12 months - 0.5 μg / day, from 1 to 3 years this need increases to 1 μg / day, from 4 to 6 years - up to 1.5 mcg / day. Children aged 7-10 years need 2 μg of vitamin per day, adolescents 11-17 years old, as well as adults - 3 μg / day. In pregnant and breastfeeding women, the need is higher - 4 mcg / day.

There is also another designation for the amount of vitamin B12 - in international units (IU). 1ME corresponds to the activity of 1 μg of cyanocobalamin.

Cobalamin metabolism in the body is very slow, and it takes at least 5-6 years to form its deficiency. If a person takes potassium supplements, then hypovitaminosis is formed several times faster.

If a person smokes, drinks alcohol, or is a vegetarian, then the need for vitamin B12 increases.

With excessive consumption of sweet, carbonated drinks, as well as with chronic diarrhea, the absorption of cyanocobalamin from the intestine worsens, which means that its intake into the body decreases.

If a person uses many different drugs, and especially contraception, the consumption of cyanocobalamin increases.

The value of vitamin B12 in the body

Vitamin B12 plays a significant role in the biological processes of the body, together with other vitamins participates in the metabolism of fats, proteins and carbohydrates, and also:

• Participates in the formation of red blood cells - erythrocytes;
• Promotes the removal of homocysteine from the body - an amino acid that contributes to the occurrence of strokes and myocardial infarctions;
• Reduces the content of fat and cholesterol in the body;
• Improves oxygen availability to cells during hypoxia;
• Takes part in the regeneration of damaged tissues by participating in the synthesis of nucleic acids;
• Promotes the formation of active forms of vitamin A;
• Participates in the formation of the hormone melatonin, which regulates biorhythms;
• It has an effect on the reproductive system of men - it increases the sperm content in the gonads;
• Regulates the immune system;
• It is a catalyst for biochemical transformations of organic acids, as a result of which myelin is formed - the sheath of nerve fibers.

Vitamin B12 is very important for hair, for its growth and healthy appearance.

Lack of vitamin B12

Hypovitaminosis is formed when there is insufficient intake of cyanocobalamin with food, a violation of its absorption, when taking certain drugs. Signs of its insufficiency are the following symptoms:

• Low content of hemoglobin, platelets and leukocytes;
• Disorders of the digestive system;
• Fatigue, irritability, depression;
• Feeling of numbness in the limbs and difficulty walking;
• Stomatitis, glossitis;
• Headaches;
• Visual impairment;
• Painful periods.

Lack of vitamin B12 for hair leads to hair loss and early graying.

Excess vitamin B12

Hypervitaminosis of cyanocobalamin is rarely formed, if the dosage is not observed while taking vitamin B12 tablets or with its parenteral administration.

The main symptoms of an overdose:

• Pulmonary edema;
• Vein thrombosis;
• Hives or anaphylactic shock;
• Heart failure.

The use of cyanocobalamin for medicinal purposes

As a medicine, vitamin B12 in ampoules or tablets is used for diseases such as hepatitis, anemia, radiculitis, polyneuritis, chronic pancreatitis, multiple sclerosis, diabetic neuropathy, radiation sickness, cerebral palsy, peripheral nerve injuries, skin and allergic diseases.

Vitamin B12 tablets are better absorbed when taken simultaneously with folic acid. It is used in the treatment of anemia at a dose of 30 to 200 mcg per day every other day, until remission is achieved.

Vitamin B12 in ampoules is used for intravenous, intramuscular, intra-lumbar and subcutaneous administration.

In case of neurological pathology, including pain syndrome, vitamin B12 is administered from 0.2 to 0.5 mg per injection on an accrual basis, once every 2 days, the course is up to 2 weeks.

Contraindications

Vitamin B12 is not used in ampoules and tablets in case of thromboembolism, erythrocytosis, individual intolerance. Concomitant angina pectoris requires careful use.

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