This paper provides a literature review on breastfeeding, selecting studies that have helped explain its benefits for maternal and child health. A search for articles published since 2000 was conducted, including relevant studies for the advancement of knowledge in previous decades. An Internet search of the PubMed and SciELO databases was performed to select the studies. Besides the aspects on which there is widespread agreement, controversial results were also included, as well as intriguing ones from the field of neurobiology. Public policy recommendations have undergone substantial changes following those new discoveries. Some studies have also been conducted to search for the most cost-effective measures to promote breastfeeding practices. This paper highlights: current recommendations on child feeding; the importance of breastfeeding for early childhood; the implications of breastfeeding for health of both the infant and mother; and the effectiveness of key interventions to encourage breastfeeding.