Definition
Circadian Rhythm
Your body's roughly 24-hour internal clock, which regulates sleep, alertness, and many metabolic processes based largely on light exposure.
The circadian rhythm is synchronised primarily by light — bright light in the morning signals wakefulness, and dim light in the evening signals wind-down. Modern life, with artificial light, screens, and irregular schedules, frequently works against this signal rather than with it.
Why it matters: aligning light exposure, meal timing, and activity with your circadian rhythm is one of the most evidence-backed, low-cost levers for improving sleep and daytime energy.
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