subject: cortisol

Does Human Milk Composition Make the Infant Body Clock Tick?

Does Human Milk Composition Make the Infant Body Clock Tick?

Human beings have internal clocks. Locked in a room with no source of daylight nor regularly scheduled stimulation, our bodies cycle automatically through periods of slightly longer than 24 hours, sleeping and waking more or less as if the sun were rising and falling over a horizon that we could see. But we are not born this way. Instead, infants develop body clocks gradually. Researchers investigating this aspect of development have recently wondered how much human milk contributes to the process, in the knowledge that its levels of nutrients and hormones vary over the course of the day. Read More...

Take It Easy: Neonatal Milk Hormones Influence Infant Social and Cognitive Behavior

Take It Easy: Neonatal Milk Hormones Influence Infant Social and Cognitive Behavior

Email, texts, IM, Facebook, Instagram—in the age of social media, there is no shortage of ways to send a message from one person to another. But is mother’s milk the original social network? Many of milk’s ingredients are believed to act as signaling factors that convey a “message” from mother to infant. Over the last decade, researchers have worked on decoding these messages, with a particular focus on the hormone cortisol. Milk cortisol levels are associated with infant growth and infant temperament in rhesus macaques, and hypothesized to send the message to be more cautious and prioritize growth over behavioral activity. A newly published study expands on this hypothesis and tests whether milk cortisol levels during the first weeks of life predict behavior and cognitive performance months later. The results suggest that far from being an instant messenger, milk’s signal may have effects well after it is received. Read More...

Breast Milk, the Synchronizer

Breast Milk, the Synchronizer

Consuming a glass of warm milk before bed is supposed to make you sleep well. This old wives’ tale is repeated on websites that offer health and nutritional advice, often backed up by the detail that milk contains tryptophan, the amino acid that is the reason eating turkey purportedly makes you sleepy. But the reality is much more complex. In fact, several compounds in milk appear to have a soporific effect. And perhaps the most intriguing thing about them is that their levels alter with the time of day that the milk is produced. Read More...

Meet our Elite and Premier Sponsors