Biological rhythms – how our body clock controls our sleep
Whether people are morning birds or night owls has a lot to do with their internal biological “clock” and their natural biological cycles or rhythms, which are known as circadian rhythms. Find out here why everyone has a different sleep-wake cycle, how important sleep is to health and what factors disrupt biological rhythms.
At a glance
- Both genetic factors and environmental stimuli determine our body’s internal functions.
- This happens within repeating cycles of equal length. These biological cycles or rhythms (biorhythms for short) are specifically referred to as circadian rhythms.
- Our body’s “master clock” is in the brain.
- When it comes to sleeping habits, people tend to be either early birds or night owls.
- Constantly living in conflict with their own internal clock can make a person ill.
- Sleep hygiene helps people maintain healthy sleeping habits.
Note: The information in this article cannot and should not replace a medical consultation and must not be used for self-diagnosis or treatment.

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Reviewed by the German Sleep Society (Deutsche Gesellschaft für Schlafforschung und Schlafmedizin e.V.).
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