How does light affect our sleep?

Light plays a crucial role in regulating sleep patterns and overall alertness. Here are key insights:

1. Morning Light Exposure: Viewing sunlight for 2 to 10 minutes in the morning triggers the release of cortisol, a hormone that promotes wakefulness and the ability to focus. It also sets a timer for melatonin production later in the day, which aids in sleep onset 1 2.

2. Blue Light: Contrary to popular belief, blue light in the morning is beneficial as it activates cells in the eye that help regulate the circadian clock. However, these cells are hard to activate early in the day, making natural sunlight far more effective than artificial light from screens 1 2.

3. Light in the Evening: To prepare for sleep, it's important to avoid bright lights of any color in the evening. Limiting light exposure, especially between 11:00 p.m. and 4:00 a.m., is crucial as bright light during these hours can disrupt dopamine levels, lower mood, and impair cognitive functions 3 4.

   
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   Optimize Your Sleep
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   Optimize Your Sleep
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   Circadian Rhythm Insights
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   Circadian Rhythm Insights
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   Morning Light Benefits
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4. Social Cues and Early Activities: Engaging in activities like social interactions or exercise (e.g., jumping rope in the morning sun) also provides wakefulness signals. These behaviors help align circadian rhythms and enhance mood through the release of dopamine 4 5.

By adopting these practices, you can significantly improve your sleep quality and overall well-being.