Mindful MeridianBrain Health
Circadian Rhythm Explained
A plain-language guide to the body's roughly 24-hour timing system and the role of light and melatonin.
Medical note: This article is educational and not medical advice. Dietary supplements can interact with medicines and may not be appropriate for everyone. Seek professional care for persistent, progressive, sudden or concerning symptoms.
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What circadian rhythm means
Circadian rhythms are roughly 24-hour biological patterns influenced strongly by light and darkness.
Where the pineal gland fits
The pineal gland secretes melatonin in a daily pattern, generally increasing in darkness and decreasing with light.
Why timing matters
Irregular sleep schedules, travel, shift work and evening light exposure can shift sleep-wake timing even when total time in bed looks adequate.
Supplements are only one piece
Melatonin products or “pineal support” supplements should not distract from basic timing cues such as consistent sleep schedules and appropriate light exposure.