How Blue Light Affects Our Sleep

13th June 2023

How Blue Light Affects Your Sleep and Ways to Minimise Its Impact

In today's digital age, we are constantly surrounded by screens emitting blue light. From smartphones and laptops to televisions and tablets, our exposure to blue light has skyrocketed. While blue light has its benefits during the day, prolonged exposure to it, especially in the evening, can significantly impact our sleep quality. In this week's blog, we will delve into the effects of blue light on sleep, explore the science behind it, and provide effective strategies to minimise its impact for a restful night's sleep.  

Understanding Blue Light

Blue light is a high-energy, short-wavelength light that falls within the visible light spectrum. It is naturally present in sunlight and helps regulate our circadian rhythm - the internal biological clock that governs our sleep-wake cycle. During the day, exposure to blue light promotes alertness, cognitive function, and mood elevation. However, excessive exposure to blue light in the evening and nighttime can disrupt our natural sleep patterns.


Effects of Blue Light on Sleep

Suppression of Melatonin

Melatonin is a hormone produced by the pineal gland in response to darkness, helping regulate our sleep-wake cycle. Blue light exposure, particularly in the evening, can suppress melatonin production, making it difficult to fall asleep. This delay in melatonin release can lead to prolonged sleep onset and decreased sleep quality. 

Disrupted Circadian Rhythm

Our bodies rely on natural light cues to regulate our circadian rhythm. Blue light exposure at night confuses our internal clock, as it mimics daylight, signalling wakefulness to our bodies. This disruption can lead to a delayed sleep phase, making it harder to fall asleep at a desired bedtime. 

Reduced REM Sleep

Rapid Eye Movement (REM) sleep is a vital stage of the sleep cycle associated with dreaming, memory consolidation, and emotional regulation. Blue light exposure before bed can interfere with REM sleep, leading to fragmented or shortened REM periods. This disruption can impair cognitive function, emotional well-being, and memory consolidation. 

Minimising the Impact of Blue Light

Limit Screen Time Before Bed

Establish a digital curfew by avoiding screens, such as smartphones, tablets, and computers, for at least one to two hours before bedtime. Engage in relaxing activities, such as reading a book, practicing gentle stretching, taking a warm bath, or engaging in mindfulness exercises.

Use Blue Light Filters

Most electronic devices offer a blue light filter feature that reduces the amount of blue light emitted from the screen. Enable this feature or use third-party applications that adjust the colour temperature of your devices' screens based on the time of day. These filters create a warmer, more sleep-friendly display, minimising blue light exposure.

Wear Blue Light Blocking Glasses

Consider investing in blue light blocking glasses that filter out a significant portion of blue light. These glasses feature specialised lenses that block specific wavelengths of blue light while allowing other wavelengths to pass through. Wearing them in the evening can help protect your eyes and promote better sleep. 

Opt for Night Mode on Devices

Activate the "Night Mode" or "Night Shift" setting available on most smartphones, tablets, and computers. This mode reduces blue light emissions and adjusts the colour temperature of the screen to a warmer hue, resembling natural evening light. It is advisable to schedule this mode to activate automatically in the evening based on your local sunset time. 

Create a Sleep-Friendly Environment

Make your bedroom conducive to quality sleep. Dim the lights in the evening to prepare your body for rest. Consider using warm, soft lighting or candles instead of bright overhead lights. Use blackout curtains or blinds to minimise external sources of light that may disrupt sleep.

Establish a Relaxing Bedtime Routine

Develop a soothing bedtime routine to signal to your body that it's time to wind down. Engage in activities that promote relaxation, such as reading a book, listening to calming music, practicing deep breathing exercises, or writing in a journal. Consistency in your routine helps reinforce a sleep-ready environment. 

Incorporate Light Management Throughout the Day

Expose yourself to natural light during the day, especially in the morning. This helps regulate your circadian rhythm and reinforces the natural sleep-wake cycle. Spend time outdoors, open curtains or blinds to let sunlight in, and consider using light therapy devices designed to mimic natural light if necessary. 

Educate Yourself and Others

Stay informed about the effects of blue light on sleep and share your knowledge with others. Encourage friends, family, and colleagues to adopt healthy sleep habits by reducing blue light exposure in the evening. 


In our digital world, managing blue light exposure is essential for promoting optimal sleep and overall well-being. By understanding the effects of blue light on sleep and implementing strategies to minimise its impact, we can create a sleep-friendly environment and support our natural circadian rhythm. Prioritising quality sleep not only enhances our energy levels and cognitive function but also positively influences our mood, productivity, and long-term health.