Causes of Iron Deficiency Anemia in Infants and Toddlers
Iron deficiency anemia is one of the most common nutritional deficiencies in infants and young children worldwide. It occurs when the body lacks sufficient iron to produce adequate hemoglobin, the protein in red blood cells responsible for carrying oxygen. This condition can impair growth, cognitive development, and immune function if left untreated. Understanding the underlying causes is essential for early detection and effective prevention.
1. Inadequate Iron Stores at Birth
Some infants are born with insufficient iron reserves, particularly those who are preterm, low birth weight, or multiples (such as twins). During the third trimester of pregnancy, the fetus typically accumulates the majority of its iron stores from the mother. Babies born prematurely miss out on this critical period, resulting in lower baseline iron levels. Without timely dietary supplementation, these infants are at a significantly higher risk of developing iron deficiency within the first few months of life.
2. Exclusive Breastfeeding Without Iron Supplementation
While breast milk is considered the gold standard for infant nutrition, it contains relatively low levels of iron—typically around 0.2–0.5 mg/L. Although this iron is highly bioavailable, exclusively breastfed infants beyond six months of age may not receive enough iron to meet their growing demands. The American Academy of Pediatrics recommends introducing iron-rich complementary foods or using iron supplements starting at around 4–6 months, especially for infants at higher risk.
Dietary Factors Contributing to Iron Deficiency
Poor dietary intake is a leading cause of iron deficiency in toddlers and older infants. As children grow, their need for iron increases due to rapid physical and neurological development. However, many caregivers may not introduce iron-rich foods such as fortified cereals, pureed meats, beans, lentils, and leafy greens at the appropriate time. Diets high in cow's milk—which is naturally low in iron and can interfere with iron absorption—can further exacerbate the problem.
3. Rapid Growth and Increased Iron Demand
Infancy and early childhood are periods of explosive growth. Blood volume expands quickly, increasing the demand for hemoglobin and, consequently, iron. If dietary iron intake does not keep pace with this accelerated growth, even previously healthy children can develop iron deficiency. This is especially true between 6 and 24 months of age, a critical window for both development and nutritional vulnerability.
4. Excessive Iron Loss
In some cases, iron deficiency results not from poor intake but from abnormal losses. Conditions such as chronic gastrointestinal bleeding, often caused by food allergies (e.g., cow's milk protein allergy), intestinal inflammation, or parasitic infections like hookworm, can lead to ongoing blood and iron loss. Though rare in very young children, heavy menstrual bleeding in adolescent girls is another significant contributor. Additionally, frequent use of certain medications or undiagnosed celiac disease can impair nutrient absorption and contribute to anemia.
Prevention and Early Intervention
Proactive measures can greatly reduce the incidence of iron deficiency anemia. These include prenatal care to support maternal iron status, timely introduction of iron-fortified foods, routine screening during well-child visits, and appropriate supplementation when needed. Parents should work closely with pediatricians to monitor developmental milestones and nutritional intake, especially during key transition phases like weaning.
By recognizing the multifactorial nature of iron deficiency anemia, healthcare providers and families can take targeted steps to ensure children receive the iron they need for optimal health and long-term well-being.