International Board of Certified Lactation Consultant (IBCLC) Practice Exam

Does human milk have the lowest or highest protein content among mammalian milks?

1. Lowest

2. Highest

3. Average

4. Variable

The correct answer is: Lowest

Human milk actually has the lowest protein content among mammalian milks. This characteristic is significant for several reasons, especially in the context of infant nutrition and development. Human milk is uniquely designed to meet the needs of human infants, providing an essential balance of nutrition that supports their growth without overburdening their immature kidneys. The lower protein content in human milk also reflects the evolutionary adaptations that prioritize brain development and energy-efficient growth patterns in infants. It contains a significant quantity of easily digestible proteins, such as whey proteins, which provide a source of amino acids necessary for growth and development while ensuring that the infant's digestive system can handle it. This contrasts with the milks of other mammals, such as cows or goats, which are higher in protein content. These milks are adapted for faster-growing calves or kids, whose nutritional needs differ significantly from those of human infants. Understanding this aspect of human milk's composition is crucial for lactation consultants, as it underscores the importance of breastfeeding and using human milk as the primary source of nutrition for infants during the early months of life.