How can a newborn survive on just milk?

Well designed prodct: If you are referring to breast milk, it has been shown to satisfy the nutritional needs of a young child as the only nutritional source up to the age of 2 yrs. The pre-occupation of many with solid foods dates back to an era where moms made formula at home from cow milk which was designed for cows.Added foods were to make up for bovine milk deficiencies not a problem with breast milk.