The truth about blue light

Does it really cause insomnia and increased risk of cancer?

LONDON: Long attached to visions of clear skies and calm seas, the colour blue historically could not be more welcome, refreshing and natural. Yet, because of the proliferation of blue-emitting LEDs in our artificially lit lives, blue light has come to represent bleary eyes, sleeplessness and the poor health associated with disruption of the circadian rhythm, reports The Guardian.

Of the spectrum of lightwaves emitted by the sun that our eyes can detect, it is the shorter “blue” ones that get reflected and bounced around most by the molecules in the Earth’s atmosphere. They are the reason the sky is blue. So why is blue light apparently so bad for us? Earlier this month, a studypublished in The Lancet Psychiatry looked at data from 91,105 middle-aged people and found that those with disrupted sleep patterns were more likely to have depression or bipolar disorder. The worst affected were described by one of the authors of the paper, Professor Daniel Smith at the University of Glasgow, as those with “very poor sleep hygiene – people on their mobile phones at midnight checking Facebook or getting up to make a cup of tea in the middle of the night”. He reiterated the now common advice from sleep experts: switch off electronic devices an hour before bedtime.

In March, the chief medical officer, Sally Davies, advised caution in using devices emitting blue light while more research is done into its potential harm. Then in April researchers at the Barcelona Institute of Global Healthlinked increased risks of breast and prostate cancers to blue light exposure at night (an association was found, but whether the light exposure caused the cancers through circadian disruption is unknown). What we do know is that undimmed LED screens and lamps give off more blue light than traditional light sources, such as incandescent lightbulbs. And we are using backlit devices more than ever, whether checking social media and bank balances or grappling with heavy workloads, right up until lights out.

 

The truth about blue light

Does it really cause insomnia and increased risk of cancer?

LONDON: Long attached to visions of clear skies and calm seas, the colour blue historically could not be more welcome, refreshing and natural. Yet, because of the proliferation of blue-emitting LEDs in our artificially lit lives, blue light has come to represent bleary eyes, sleeplessness and the poor health associated with disruption of the circadian rhythm, reports The Guardian. Of the spectrum of lightwaves emitted by the sun that our eyes can detect, it is the shorter blue ones that get reflected and bounced around most by the molecules in the Earths atmosphere. They are the reason the sky is blue. So why is blue light apparently so bad for us? Earlier this month, a studypublished in The Lancet Psychiatry looked at data from 91,105 middle-aged people and found that those with disrupted sleep patterns were more likely to have depression or bipolar disorder. The worst affected were described by one of the authors of the paper, Professor Daniel Smith at the University of Glasgow, as those with very poor sleep hygiene people on their mobile phones at midnight checking Facebook or getting up to make a cup of tea in the middle of the night. He reiterated the now common advice from sleep experts: switch off electronic devices an hour before bedtime. In March, the chief medical officer, Sally Davies, advised caution in using devices emitting blue light while more research is done into its potential harm. Then in April researchers at the Barcelona Institute of Global Healthlinked increased risks of breast and prostate cancers to blue light exposure at night (an association was found, but whether the light exposure caused the cancers through circadian disruption is unknown). What we do know is that undimmed LED screens and lamps give off more blue light than traditional light sources, such as incandescent lightbulbs. And we are using backlit devices more than ever, whether checking social media and bank balances or grappling with heavy workloads, right up until lights out.