Functions and role of iron in the human body
Among the many elements involved in metabolic processes in the human body, none is as important as iron. The highest concentration of iron is in erythrocytes - red blood cells, more precisely - in hemoglobin. A small proportion of iron is found in the blood plasma and in the tissues of the human body as part of ferritin, hemosiderin and transferrin.
The rate of iron content in the blood and in other tissues of an adult is 4-7 grams (total).
If the body loses iron for any reason, iron deficiency anemia occurs. To detect it, the determination of serum iron in the blood is carried out.
Content:
- The rate of iron in the body
- Functions and biological significance of Fe in the blood
- Increased content
- Lack of iron in the body
- How to increase the level of iron in the blood?
The rate of iron in the body
Iron is found in blood serum due to transferrin (25%), which binds and transports it by the protein. To order a test for the determination of serum iron, a base is required - a low level of hemoglobin, usually found as part of a complete blood count.
During the day, the concentration of Fe in the body fluctuates:
- 14.3-25.1 mmol / l in men;
- 10.7-21.5 mmol / l - in women.
The differences are due to the presence of menstrual bleeding in women, they wear off with age. Iron deficiency is increasingly defined with age, in both women and men.
The norm of a trace element depending on gender and age:
| Gender and age | Norm in μmol / l |
| Infants up to one year | 7.16 - 17.9 |
| Children and adolescents from one to 14 years old | 8.95 - 21.48 |
| Boys and grown men | 11.64 - 30.43 |
| Girls and grown women | 8.95 - 30.43 |
To get objective indicators, you need to follow the rules when passing the analysis:
- Donate blood on an empty stomach (at least 12 hours before analysis);
- Stop taking pills for the treatment of IDA at least a week in advance;
- Do not get tested several days before the blood transfusion.
To determine the Fe level, blood serum is used, placing it after sampling in a dry test tube, which has never been used before, which has not been exposed to detergents.
Functions and biological significance of Fe in the blood
Not a single living organism can do without iron, because it performs the following functions:
- Provides tissue respiration with a trace element concentrate in the blood;
- Provides full activity of skeletal muscles.
Erythrocytes and blood hemoglobin bind oxygen that has entered the lungs from the environment, carry it throughout the human body, and carry out carbon dioxide formed as a result of gas exchange.
The divalent Fe ion plays a leading role in the activity of hemoglobin to ensure respiratory activity. Under the influence of strong oxidants, it becomes trivalent, turning into methemoglobin. Erythrocytes containing methemoglobin pass through hemolysis and are destroyed. As a result, the tissues enter a state of acute hypoxia.
The synthesis of iron by the human body is impossible, it comes with food: meat, fish, vegetables and fruits. For the complete extraction of Fe from food, a large amount of ascorbic acid is needed, then the assimilation of a trace element from animal products increases several times.
There is a precise mechanism for regulating the absorption of iron in the small intestine: if there is not enough iron, an increased absorption of the trace element begins, if there is an excess of iron, a blockage of the process begins. There is no absorption of iron in the large intestine. The need for Fe intake in the body is 2-2.5 mg, women need more, since they monthly lose at least 10 mg of this trace element with every 20 ml of blood.
Increased content
An excessive concentration of Fe in the blood, as well as its lack, speaks of existing pathologies. Since the mechanism for regulating the absorption of this microelement is quite reliable, an increased iron content indicates its breakdown or an increased breakdown of erythrocytes and the corresponding release of ions of this element.
The reasons for the increased level of Fe in the body:
- Hemolytic, folate deficiency, aplastic, B 12 - anemia, thalassemia;
- Increased absorption in the small intestine in violation of restrictions (hemochromatosis);
- Hemosiderosis due to an overdose of drugs with a high Fe content, or multiple blood transfusions;
- Lead poisoning, side effects of oral contraceptives, sideroachrestic anemia, which caused a failure of hematopoiesis in the inert brain;
- Hepatitis of any etiology, liver necrosis, hepatopathy, acute cholecystitis.
When studying the test results, it is important to take into account the possible use of iron preparations for oral use by patients.
Lack of iron in the body
Since iron is not produced by the human body, and few people calculate its content in the diet, after a while its deficiency begins to be felt. Fe deficiency causes anemia and is manifested by the following symptoms:
- "Flies before the eyes";
- Dry and pale skin;
- Dizziness;
- Brittle nails;
- Dryness and hair loss.
Reasons for a decrease in the concentration of iron in the circulatory system:
- Lack of an element in food when switching to a vegetarian diet, excessive consumption of fatty foods that do not have iron in the composition, or dairy diets when calcium prevents Fe from being absorbed.
- Increased need for various trace elements, including iron, during lactation and pregnancy, during the period of rapid growth in childhood and adolescence.
- Diseases of the gastrointestinal tract, leading to iron deficiency anemia, as they prevent the absorption of iron through the intestinal walls: gastritis, enterocolitis, enteritis, condition after resection of the stomach or small intestine, neoplasms.
- Osteomyelitis, myocardial infarction, rheumatism, purulent, inflammatory, septic infections, tumors with rapid growth dynamics, when Fe is actively absorbed from blood plasma by phagocytes.
- Hemosiderosis, when hemosiderin accumulates in the tissues of the body, which leads to a decrease in the level of iron in the blood.
- Chronic renal failure leading to a deficiency of erythropoietin in the kidneys.
- Nephrotic syndrome, in which iron is actively excreted in the urine.
- Prolonged bleeding: menstrual, hemorrhoidal, nasal, etc.
- An active reaction of hematopoiesis with a pronounced use of iron.
- Malignant and benign tumors, cirrhosis, liver cancer.
- Obstructive jaundice caused by stagnation of bile (cholestasis).
- Deficiency of vitamin C, which promotes the absorption of iron.
How to increase the level of iron in the blood?
It is difficult to increase the Fe level without knowing the reasons for its decrease. Even a diet rich in micronutrients cannot affect this process if the absorption of iron is impaired. In order not only to ensure the transit of iron through the gastrointestinal tract, but to fully influence the cause of its decrease, you need to be guided by the doctor's recommendations and undergo a full examination.
Foods for saturating the diet with iron:
- Meat: rabbit, steamed lamb, veal, beef, turkey, goose. Pork lard has no Fe in its composition at all.
- The liver of animals, which is the organ of hematopoiesis. It is important to be aware of the possible high levels of toxins, and not to include organ meats too often.
- Poultry eggs contain little iron, but they are rich in phospholipids, vitamins B 1, B 12;
- Buckwheat as the best product against iron deficiency anemia.
- Eating vegetables and fruits to replenish stores of ascorbic acid, which helps to absorb iron through the intestinal wall. Citrus fruits (lemon, orange) and sauerkraut are best suited for this. You can eat vegetables and fruits rich in Fe: apples, peas, beans, prunes, spinach, but from them the trace element penetrates into the digestive tract in a minimal amount.
Foods rich in calcium (cottage cheese, milk, cheese) interfere with the full absorption of Fe, so they are consumed separately from food rich in this trace element.
The body will not allow an excess of iron, even with its excessive use, since it has mechanisms for regulating the exchange of trace elements.
Video story about iron and iron deficiency anemia:
The author of the article: Shutov Maxim Evgenievich | Hematologist
Education: In 2013 he graduated from the Kursk State Medical University and received a diploma "General Medicine". After 2 years, completed residency in the specialty "Oncology". In 2016 completed postgraduate studies at the National Medical and Surgical Center named after N. I. Pirogov.
