Can you "reprogram" your biological clock?

Partially. Chronotype (lark/owl) is largely genetically determined, and it cannot be radically changed. But the amplitude and stability of the circadian rhythm can be significantly improved through: consistent wake-up time, light signals, eating patterns, and physical activity. This is a "fine-tuning" of the clock, not a change of the mechanism.

Night shifts: How harmful are they in the long term?

Chronic night shift work is a proven risk factor for: cancer (especially breast cancer), cardiovascular diseases, type 2 diabetes, and depression. The WHO classifies circadian rhythm-disrupting shift work as a "probable carcinogen". If night shifts cannot be avoided, it is especially important to prioritize other health components (nutrition, physical activity, sleep in darkness).

Circadian Rhythms: How Your Internal Biological Clock Controls Your Health

Circadian rhythms are the body's internal biological clock. How they work, why they get disrupted, and how to restore synchronization.

🌿psybot.app·June 19, 2026·2 min read

The 2017 Nobel Prize in Physiology or Medicine was awarded for the discovery of the molecular mechanisms of circadian rhythms. This underscores how fundamentally important this system is for our health. But most people live in constant conflict with their own biological clock.

1. What a Circadian Rhythm Is

A circadian rhythm is an approximately 24-hour cycle of biological processes in the body, controlled by internal "clocks" (the suprachiasmatic nucleus of the hypothalamus). It regulates sleep and wakefulness, hormone production, body temperature, immune response, metabolism, and much more.

2. The Main Synchronizer — Light

Light is the main "time-setter" for circadian rhythms. Morning light inhibits melatonin production and signals the body: "the day has begun." Evening blue light (screens) sends a false signal of "still daytime" — shifting the sleep phase.

3. Consequences of Circadian Rhythm Disruption

Sleep disruptions: difficulty falling asleep at the right time, daytime sleepiness
Metabolic disorders: increased risk of obesity and type 2 diabetes
Cognitive impairment: memory, concentration, reaction speed
Disrupted immune response
Increased risk of depression and anxiety disorders

4. How to Synchronize Circadian Rhythms

Regular wake time — more important than regular sleep time. Morning bright light (sun or daylight lamp) for 30-60 minutes after waking. Reduced brightness and "warm" lighting in the evening. Limiting screens 1-2 hours before sleep. Regular meal times.

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Disclaimer

This article is for informational and educational purposes only. It is not a substitute for professional psychological advice, diagnosis, or treatment. If you are in a crisis situation, please reach out to a qualified mental health professional or a crisis helpline.

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