When should full-term infants begin oral iron supplementation?

Full-term infants typically begin oral iron supplementation at around 4-6 months of age due to the depletion of maternal iron stores and the need to support the increasing iron requirements as they grow. During this period, infants' iron reserves, which were sufficient at birth, start to diminish, especially if they are exclusively breastfed, as breast milk does not contain adequate amounts of iron to meet their needs beyond this timeframe.

At around 4-6 months, infants also begin introducing solid foods into their diets, and it's essential that iron-rich foods be incorporated to prevent iron deficiency anemia, which can have long-term developmental consequences. Iron supplementation during this stage helps to ensure they have enough iron for proper growth and cognitive development.

Introducing iron too early, before 4 months, may pose risks such as gastrointestinal issues or an increased risk of infections. Delaying beyond 6 months can lead to iron deficiency due to insufficient dietary intake, especially in breastfed infants. Thus, recommending iron supplementation at 4-6 months aligns with current pediatric guidelines and reflects the changes in an infant's iron requirements as they transition into solid foods.