page_title: Circadian rhythm
section_title: Human health
hierarchical_section_title: Circadian rhythm / Human health
caption_attribution_description: Español: Dos personas durmiendo la siesta en los alrededores del Kiosko Alfonso, en A Coruña (Galicia, España). English: A couple of guys sleeping near the Kiosko Alfonso in A Coruña (Galicia, España. Galego: Dúas persoas durmindo a sesta nos arredores do Kiosko Alfonso, na Coruña (Galicia, España).
context_page_description: A circadian rhythm is a natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours. It can refer to any biological process that displays an endogenous, entrainable oscillation of about 24 hours. These 24-hour rhythms are driven by a circadian clock, and they have been widely observed in plants, animals, fungi, and cyanobacteria.
  The term circadian comes from the Latin circa, meaning "around", and diēm, meaning "day". The formal study of biological temporal rhythms, such as daily, tidal, weekly, seasonal, and annual rhythms, is called chronobiology. Processes with 24-hour oscillations are more generally called diurnal rhythms; strictly speaking, they should not be called circadian rhythms unless their endogenous nature is confirmed.
  Although circadian rhythms are endogenous, they are adjusted to the local environment by external cues called zeitgebers, which include light, temperature and redox cycles. In medical science, an abnormal circadian rhythm in humans is known as circadian rhythm disorder.
  In 2017, the Nobel Prize in Physiology or Medicine was awarded to Jeffrey C. Hall, Michael Rosbash and Michael W.
context_section_description: Timing of medical treatment in coordination with the body clock, chronotherapeutics, may significantly increase efficacy and reduce drug toxicity or adverse reactions.
  A number of studies have concluded that a short period of sleep during the day, a power-nap, does not have any measurable effect on normal circadian rhythms but can decrease stress and improve productivity.
  Health problems can result from a disturbance to the circadian rhythm. Circadian rhythms also play a part in the reticular activating system, which is crucial for maintaining a state of consciousness. A reversal in the sleep–wake cycle may be a sign or complication of uremia, azotemia or acute kidney injury.
  Studies have also shown that light has a direct effect on human health because of the way it influences the circadian rhythms.
caption: A short nap during the day does not affect circadian rhythms.
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