On occasions when there is an iron deficiency in the diet, it is necessary to take this mineral which is present in greater quantities in the blood and is found in all living cells as a supplement. It is the main component of haemoglobin inside red blood cells and it plays a fundamental role in the body as the main transporter of oxygen to all its cells, intervening in the production of energy.
Likewise, iron is present in respiratory enzymes and in myoglobin, a protein that transports and supplies oxygen to muscle cells. Therefore, iron deficiency (sideropenia) reduces the blood's ability to transport oxygen.
The importance of iron in the immune system
Iron is a fundamental element for the normal development of the immune system and its proper functioning. So much so, that an iron deficiency can significantly affect the body's ability to generate a response to infectious agents.
This is because iron is an essential mineral for the proliferation and maturation of immune cells. As a consequence, its deficit causes a lower count of all leukocytes, as well as a reduction in their ability to neutralise pathogens.
In parallel, iron deficiency can cause a lower skin response to antigens. This means that the protective barrier of the skin, which acts as a natural shield against external aggressions, loses part of its defensive function.
Iron requirements for babies
Newborns, with the exception of premature babies, rarely have low iron levels before they are six months' old. During this period, the baby's iron needs are fulfilled by mobilising the deposits of this mineral that have been acquired from the mother during pregnancy.
After the first six months of their life, it is common for babies to reach the limit of their iron reserves.
In certain circumstances, despite feeding babies a diet rich in iron, adequate levels of this nutrient are not obtained, so supplementation with this mineral is necessary. For example, there is an increased risk of iron deficiency for babies when breastfeeding continues beyond the first six months.
Iron deficiency in children and adolescents
After breastfeeding, it is not uncommon to meet children who are poor eaters, have behavioural eating disorders, or follow diets that are low in iron-rich foods.
Adolescents are also a population group at risk of iron deficiency as they have a significant requirement for this mineral in order to achieve the accelerated growth and changes in body composition.
Between the age of 10 and 18 years around 15-25% of adult height and 40-45% of adult weight are acquired. At the same time, there is an increase in bone and muscle mass and an expansion of total blood volume, resulting in increased iron needs. This requirement is accentuated in girls with the arrival of the menarche – their first menstrual period-. With the onset of menstruation they are 10 times more likely to develop anaemia than boys.
Along with these metabolic changes and pubertal development, other associated factors come together, such as intense physical-sports activity that, according to different studies, can cause between 15% and 20% of iron deficiency, increased cognitive effort due to academic demands, and the risk of falling into unbalanced dietary habits. In all cases, the doctor may recommend iron supplementation in the required doses.