Sleep glossary
circadian rhythm
Updated
Think of it as your internal day-night clock, influenced by light, timing, activity, and regular habits.
Plain-English definition
Circadian rhythm is the body's roughly 24-hour timing pattern that helps coordinate alertness, sleepiness, and daily routines.
Think of it as your internal day-night clock, influenced by light, timing, activity, and regular habits.
Why it matters
Wake-up lights, evening light choices, and consistent schedules are easier to compare when you understand this timing system.
Buying relevance
Use this term as a practical buying clue, then check the current manufacturer wording, setup guidance, materials, and returns policy. It should not be treated as a medical claim or a guarantee of how a product will work for you.
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Related glossary terms
FAQs
Is circadian rhythm a product feature?
No. Product listings may mention it, but it is a biological timing concept rather than a feature guarantee.