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Circadian Rhythms

Circadian rhythm's or 24-hour cycles are driven by the body's "biological clock." The "biological clock" is regulated by light or darkness, which can make the body think it is time to sleep or wake up.

The 24-hour circadian rhythm controls functions such as:

  • Sleeping and waking.
  • Body temperature.
  • The balance of body fluids.
  • The way other body systems function.
ByHealthwise Staff
Primary Medical ReviewerKathleen Romito, MD - Family Medicine
Specialist Medical ReviewerAlfred Lewy, MD, PhD - Psychiatry
Last RevisedJuly 7, 2010

WebMD Medical Reference from Healthwise

Last Updated: July 07, 2010
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