Human breast milk is more than a meal — it's also a clock, providing time-of-day information to infants. The composition of breast milk changes across the day, giving energizing morning milk a different cocktail of ingredients than soothing evening milk. Researchers believe this "chrononutrition" may help program infants' emerging circadian biology, the internal timekeeper that allows babies to distinguish day from night.
What happens, though, when babies drink milk that does not come directly from the breast, but is pumped at different times of day and stored in advance of feeding? Scientists have rarely considered the potential effects of "mistimed" milk on infants' development, but the implications are potentially far-reaching.