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What happens during iron deficiency anemia?
Medical expert of the article
Last reviewed: 05.07.2025
There is a certain sequence in the development of anemia:
Stage I iron deficiency anemia in children
Iron reserves in the liver, spleen and bone marrow decrease.
At the same time, the concentration of ferritin in the blood serum decreases, and a latent iron deficiency develops - sideropenia without anemia. Ferritin, according to modern concepts, reflects the state of the total iron reserves in the body, thus at this stage the iron reserves are significantly depleted without a decrease in the erythrocyte (hemoglobin) fund.
Stage II iron deficiency anemia in children
Decreased iron transport (its transport pool) or decreased saturation of transferrin with iron. At this stage, a decrease in plasma iron concentration and an increase in the total iron-binding capacity of plasma are observed, the latter due to an increase in transferrin synthesis in the liver with iron deficiency.
Stage III iron deficiency anemia in children
Reduced iron supply to the bone marrow - disruption of hemoglobin and erythrocyte formation. At this stage, there is a decrease in hemoglobin concentration in the blood and erythrocyte, a decrease in hematocrit and a change in the diameter of the erythrocyte and shape (microcytosis, anisocytosis), hypochromia of erythrocytes. There is a decrease in the activity of iron-containing and iron-dependent enzymes. A decrease in the number of erythrocytes and their oxygen-transport capacity leads to the occurrence of hypoxia, as a result of which mixed acidosis develops with subsequent disruption of the functions of organs and systems, to disruption of metabolic processes in them.
Studies have shown that children with iron deficiency anemia have a deficiency of a number of vitamins - A, C, E (the latter ensures the function of red blood cell membranes), vitamin C is involved in the processes of iron absorption in the gastrointestinal tract, and vitamin A deficiency leads to a disruption in the mobilization of iron from the liver.
Iron deficiency leads to a decrease in the number of T-lymphocytes, suppression of cellular immunity, which causes an increase in viral diseases (examine all children who frequently suffer from acute respiratory viral infections for iron deficiency).
With sufficient iron intake from the mother, the child uses it completely in the first 5-6 months for growth. Subsequently, the need for iron is covered only with food. Late introduction of vegetable puree, one-sided carbohydrate nutrition (porridge), lack of animal protein in the diet (late introduction of complementary foods in the form of minced meat), rickets, hypotrophy, and repeated diseases predispose to the development of latent iron deficiency.