Circadian rhythm

Circadian rhythms are physiologic and behavioural cycles with a recurring periodicity of approximately 24 hours.  The suprachiasmatic nucleus (SCN) synchronises the earth’s rotation with adjustments to the circadian rhythm.  The circadian rhythm coordinates many biological processes, including the sleep-wake cycle, body temperature, hunger, hormone secretion, glucose homeostasis, and the cell cycle. These processes must also be synchronised.

Desynchronisation can have significant physiological effects, particularly on ”energy levels” and behaviour. Circadian rhythm disorders are associated with mood disorders, cognitive decline, and increased risk of cardiometabolic disorders. Research to identify biomarkers of circadian timing is helping the understanding of circadian rhythms and treating these disorders.