Where is the milk made?
Milk is made in the breasts by a special type of cell which lines the millions of little sacs present in a lactating breast. These sacs are called alveoli and develop at the ends of ducts. During the let-down the alveoli are squeezed by surrounding muscle fibers forcing the milk out of the alveoli and into the duct. The lower fat milk (foremilk) enters the duct first and the higher fat milk (hindmilk) follows later.