Tailor-made for your baby. It is not yet known exactly how breast milk is innately tailored to you and your baby. That's why we're committed to continuous. Mature milk contains water, fat, carbohydrates, protein, vitamins and minerals, amino acids, enzymes, and white cells. Over the course of a feeding, breast milk changes from foremilk, high in water and lactose, to hindmilk, high in fat and calories.