What is Blue Light and How is it Affecting Your Sleep?

We’re all guilty of using our phones before bed, whether that’s looking through Instagram, catching up with friends, or trying to complete the day’s Wordle. But did you know this late-night scrolling could be ruining your sleep?

Written in collaboration with Written in collaboration with Vikki Revell

Senior Lecturer in Translational Sleep and Circadian Physiology

That’s right, the cause of a bad night’s sleep could be right in front of you! It's well known that endlessly scrolling can impact our mental health, but did you know it could be keeping you up at night too? Research has shown that using your phone for at least half an hour before bed contributes to poor sleep quality, due to its alerting blue light and stimulating content.

What is blue light?

Blue light naturally comes from the sun and plays a key role in regulating our circadian rhythm, otherwise known as our body clock. This blue light prompts the decrease in melatonin production (the hormone that makes us sleepy), so we feel awake and ready for the day. Due to the modern world we live in (and the amount of time we spend staring at screens!), blue light is more commonly found in digital devices. While blue light is great for making us feel energised in the morning, exposing ourselves to it in the evening can have a detrimental effect on our sleep.

“Light is crucial for keeping your daily (circadian) clock in your brain synchronised to the 24-hour day. This clock drives daily rhythms in nearly all aspects of your physiology and behaviour, including your sleep-wake patterns. Blue light is the most effective colour of light, not only for keeping your clock on time but also for improving your mood, how alert you feel and how well you perform both mentally and physically. However, its alerting quality is not conducive to a good night’s sleep. In the evening hours before we go to bed, we should try and reduce the amount of blue light we are exposed to as it decreases the production of melatonin, making us feel more alert and less sleepy.” Vikki Revell, Senior Lecturer in Translational Sleep and Circadian Physiology

Bodyclock Glow 150 wake-up light

Struggle to switch off?

As well as this alerting blue light confusing our sleep/wake cycle, what we're consuming on our phones makes it difficult for our brains to switch off. When we experience this over-stimulation from content on our devices, our bodies increase their production of cortisol (the stress hormone), which can prompt feelings of anxiousness.

“To get the best sleep, we should try to create an environment that is dark, quiet and has no distractions such as a mobile phone. Not only does reading our emails or the news in bed affect our ability to switch off, but also the light from electronic devices will wake us up. Instead, you can try a Lumie wake-up light. They offer a sunrise and sunset setting, to gradually wake you in the mornings and gently send you to sleep with a fading sunset. This light signal will not only help you to wake up on time but will also make you feel better and more ready to get on with your day.” Vikki Revell, Senior Lecturer in Translational Sleep and Circadian Physiology

Bodyclock Shine 300 wake-up light

Time to make the swap!

Take Vikki Revell’s expert advice and banish your phone from the bedroom. Swap your phone’s blue light, harsh alarm, and non-stop buzzing for a Lumie wake-up light. Not only do they wake you with a gradually brightening light, but they also offer a fading sunset at bedtime (with a low-blue light option), creating an environment for your best night's sleep.

Click here for more research on how light therapy can improve your sleep, and discover our full range of wake-up lights to improve your sleep hygiene.