Mature Breast -

: A thick, yellow "pre-milk" concentrated with antibodies to jumpstart the immune system.

Mature milk is roughly to keep the baby hydrated, while the remaining 10% contains a complex mix of essential nutrients: Physiology, Breast Milk - StatPearls - NCBI Bookshelf mature breast

Breast milk transitions through three distinct phases to meet a growing infant's needs: : A thick, yellow "pre-milk" concentrated with antibodies