Compositions comprising melatonin and one or more carotenoids and methods for using such compositions for enhancing cognitive and related functions such as reducing or preventing a decline of social interaction, reducing or preventing age-related behavioral changes, increasing trainability, improving attention, maintaining optimal brain function, facilitating learning and memory, reducing memory loss, and preventing or treating cognitive decline caused by dementia in an animal. Preferably, the compositions are food compositions useful for enhancing cognitive function in humans and companion animals.
