Circadian rhythms

Circadian rhythms, 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.

Is it an emergency?

If you or someone in your care has chest pains, difficulty breathing, or severe bleeding, it could be a life-threatening emergency. Call 9-1-1 or the local emergency number immediately.
If you are concerned about a possible poisoning or exposure to a toxic substance, call Poison Control now at 1-800-567-8911.

Thanks to our partners and endorsers: