For centuries, many believed that the lactating woman's diet could influence the composition and flavor of her milk and that substances in human milk could be transmitted from the wet nurse or mother and have long-lasting effects on the child. The research described herein focuses on mother's milk as a medium of early sensory experiences for the human infant and establishes several points. First, human milk is not a food of invariant flavor. Rather, like the milk of other mammals, human milk is flavored by ingested compounds such as garlic, mint, vanilla, and alcohol and provides the potential for a rich source of varying chemosensory experiences to the infant. Second, the infants' response to a particular flavor in milk may depend upon the recency and duration of past exposures. That is, the prior diet of mothers, and consequently their infants, may modify the infants' responses to these flavors during breastfeeding.