ArgumentAt the turn of the twentieth century the Norwegian market flourished with milk products intended for infants. But medical doctors argued in favor of “going back to nature”: Women ought to breastfeed their children. This paper explores how a re-naturalization of mother's milk emerged within experimental medicine. The prescribed “natural way” did not develop within medicine alone. The paper demonstrates how the natural developed within a relational space of different versions of milk: the free-market milk, the dirty and decaying milk, and the non-nutritional milk. But why did Norwegian mothers, in contrast to the development in for instance the US, continue to breastfeed their infants? Drawing on the work of the leading pediatrician Theodor Frølich, the paper suggests that this may in part be explained by the development of a distinct version of care: A matter-of-fact, pragmatic and flexible version of care that nevertheless came to enact mother's milk as the supreme form of nutrition to which there was hardly a competing or healthy alternative. “The natural way” became a thought style and was made integral to everyday culture.