International Board of Certified Lactation Consultant (IBCLC) Practice Exam

What is the primary function of lysozyme in human milk?

1. Enhance fat absorption

2. Reduce inflammation

3. Split cell walls of certain bacteria

4. Provide additional calories

The correct answer is: Split cell walls of certain bacteria

Lysozyme serves a crucial role in the infant’s immune defense by splitting the cell walls of certain bacteria. This enzyme is a type of antimicrobial agent found in human milk that specifically targets gram-positive bacteria, helping to protect the nursing infant from infections. The presence of lysozyme in human milk contributes to the overall antimicrobial properties of breast milk, promoting a healthy gut flora and enhancing the infant's immune system. While fat absorption, reducing inflammation, and caloric content are important aspects of human milk, they are not the primary function of lysozyme. Fat absorption is primarily aided by other components such as lipids and fatty acids, and while certain immunological factors in milk may help with inflammation, lysozyme's specific action is focused on bacterial cell walls. Additionally, the provision of calories is due to the macronutrients present in milk, rather than the function of lysozyme.