The first 2 years of life have been recognized as a critical window for obesity prevention efforts. This period is characterized by rapid growth and development and, in a relatively short period of time, a child transitions from a purely milk-based diet to a more varied solid-food diet. Much learning about food and eating occurs during this critical window, and it is well-documented that early feeding and dietary exposures predict later food preferences, eating behaviors, and dietary patterns. The focus of this review will be on the earliest feeding experiences - breast- and formula-feeding - and the unique role of breastfeeding in shaping children's food preferences. Epidemiological data illustrate that children who were breastfed have healthier dietary patterns compared to children who were formula-fed, even after controlling for relevant sociodemographic characteristics associated with healthier dietary and lifestyle patterns. These dietary differences are underlined, in part, by early differences in the opportunities for flavor learning and preference development afforded by breast- versus formula-feeding. In particular, the flavors of the mothers' diet are transmitted from mother to child through the amniotic fluid and breastmilk. The flavors experienced in these mediums shape later food preferences and acceptance of the solid foods of the family and culture onto which the infant is weaned. All infants learn from flavor experiences in utero, but only breastfed infants receive the additional reinforcement and flavor learning provided by continued repeated exposure to a wide variety of flavors that occurs during breastfeeding. Given the numerous benefits of breastfeeding, promotion of breastfeeding during early infancy is an important focus for primary prevention efforts and should be combined with efforts to ensure that mothers consume healthy, varied diets during pregnancy and lactation, and expose their infants to a wide array of foods during weaning and solid-food feeding.