IBCLC Practice Exam 2025 – All-in-One Guide to Excelling in Your Lactation Consultant Certification!

The correct choice is lactose, as colostrum contains lower levels of lactose compared to mature milk. Colostrum, which is produced in the first few days after childbirth, is designed to meet the immediate needs of the newborn. It is rich in antibodies and nutrients, but its lactose content is comparatively lower than that found in mature milk, which develops later.

Mature milk has a higher lactose concentration, contributing to the energy needs of the growing infant and promoting the growth of beneficial gut bacteria. In contrast, colostrum prioritizes immunological protection and easy digestibility over higher energy content, leading to different levels of lactose during this early stage of lactation.

While colostrum does contain higher amounts of protein and immunoglobulins and is lower in fat compared to mature milk, the specific focus here is on lactose, making it the best answer. Sodium levels in colostrum are not highlighted as being distinctly lower than in mature milk, which is why they don't pertain directly to this question concerning lactose.