IBCLC Practice Exam 2026 – Complete Preparation Guide

Breast milk contains a variety of immune cells that play a crucial role in protecting infants from infections and supporting their developing immune systems. Macrophages and lymphocytes are the primary types of white blood cells found in breast milk.

Macrophages are important for their ability to phagocytize pathogens, which helps to protect infants from infections. They can also secrete various cytokines that are important for immune regulation. Lymphocytes, particularly T and B cells, are essential for cell-mediated immunity and humoral responses, respectively. They contribute to the adaptive immune response, helping the infant to develop a more robust immune system over time.

The presence of these cells in breast milk not only provides immediate immune protection to the newborn but also supports the development of the infant's immune system, enabling a more sophisticated response to pathogens as the child grows. This unique composition of immune cells is one of the many benefits of breastfeeding, underscoring its role in promoting health and vitality in infants.