[Comment] Circadian and sleep medicine: challenges and future directions for metabolic and endocrine research

Circadian and sleep biology together define the temporal architecture of metabolic and endocrine physiology. Both the endogenous circadian clock and the homoeostatic drive for sleep regulate energy balance, hormone secretion, and tissue metabolism. Misalignment between these systems and behavioural schedules, through shift work, jet lag, or sleep restriction, has emerged as a potent driver of obesity, insulin resistance, as well as cardiometabolic disease.1,2