In my BioClock project we will promote health and combat disease by strengthening the 24-hour rhythm in the clinic. This project focuses on improving development and health by strengthening circadian rhythms in early life, with focus on the preterm infant. My specific focus is the intervention trial in which we will investigate the introduction of light/dark cycling during the hospital admission in preterm infants. Moreover, we focus on human milk and the presence of a circadian rhythm in milk composition.