The dark side of blue light: avoid LED-induced sleep loss

Sleep is vital for our health. The more you avoid your phone at night, the better

Until the advent of artificial lighting, the sun was the major source of lighting, and people spent their evenings in (relative) darkness. Now, we are illuminated into the small hours but we may be paying a price for basking in all that light.

At night, light throws the body’s circadian rhythm out of whack. Sleep suffers and research shows it may contribute to cancer, diabetes, heart disease and obesity. So, how can we avoid it?

During the day, practise not reacting to incoming alerts or notifications on your phone. Don't check it every time it beeps. Turn off notifications and check every 15 minutes, and gradually increase that to 30 minutes or more. Do you really need to have notifications enabled for Facebook, What's App, Snapchat, Instagram, Twitter, every news outlet (aside from The Irish Times) and more? Doubtful.

Expose yourself to lots of bright light during the day. This will boost your ability to sleep at night, as well as your mood and alertness during daylight.


Download a “do not disturb” app and use it. The apps allow you to set a period during which your phone is, usually, pushed into flight mode and, therefore, disabled from connecting to the internet or taking calls. Bliss.

During the last hour before bed, stop using your phone, tablet or laptop. Instead, choose an activity that your brain will find predictable which will, therefore, avoid anxiety. Try to avoid bright screens but, if you must, watch a (calm) TV show that you love. Better still, use a dim red light to read a book. Red light has the least power to shift circadian rhythm and suppress melatonin.

Listen to a favourite music playlist on low volume. If the device on which you are listening has internet access, set it on airplane mode.

Put your devices in a room other than your bedroom. Yes, you will need to buy an old-fashioned alarm clock (or a modern light-up alarm), but it will be worth it. If this is all too much, at least move them out of arm’s reach.

If you wake in the middle of the night, sing a song lyric (not the whole song), count sheep or concentrate on your breathing. Do not check the time on your phone.

There are, of course, apps for this. Most fitness trackers – from wristbands to smartwatches – come with an app that logs your deep sleep and light sleep, enabling you to see where you can improve and adjust the factors that make a difference.

And for those who simply don’t have the self-control to put down their devices before bedtime? Amber-tinted glasses that block blue light are highly effective at improving sleep quality and mood. Here’s to an orange future.