Fact/Fiction: Does wearing sunglasses in bed improve teenagers’ sleep?

How it was told

It might sound like a privilege reserved for Bono or other shades-loving celebs, but wearing sunglasses to bed is the secret to a peaceful 40 winks, according to some news outlets last week.

A study by the Amsterdam UMC hospital into how blue light from using phones or watching television before bed affects teenagers’ sleeping patterns attracted a lot of media attention and, unusually, quite a few different approaches to reporting it.

Take The Guardian, for example, which opted not to lead with the glasses angle, instead focusing on the other area of the study – namely screen-time abstinence, in “Limiting screen use for one week may improve teenagers’ sleep – study”.

For other newspapers, they had their eye on the glasses used in the study. The Daily Telegraph opted for “Wearing glasses to knock out blue light before bed can stop sleep disruption” while The Independent went with “Special glasses may reduce sleep-disrupting effects of smartphones, study suggests”.

And then that brings us to the Daily Star, The Sun and Mail Online. They all focused on the use of sunglasses to block out the offending blue light that is disrupting sleep. For example, in The Sun: “EN-LIGHT-ENING: Wearing SUNGLASSES to bed ‘helps you sleep better after just one week’”.

The Daily Star’s own approach deserves particular scrutiny as it opts for the headline “Snowflakes told to sleep in SUNGLASSES to stop looking at phones”. How dare those teenagers want a decent night’s kip, eh?

But who has seen the light and who is left in the dark by this study?

Facts. Checked

It is true that researchers found that screen-time abstinence and wearing blue light-blocking glasses can help to improve sleep for teenagers – but it is incredibly misleading to suggest that sunglasses would make the difference.

The study tested Dutch youngsters aged from 12 to 17 in two groups – one for youngsters who use screens for more than four hours and another for less than one hour per day.

The first group were assessed on three evenings per week for five weeks during habitual screen use, while wearing blue light-blocking glasses and while refraining from screen use. The second group of infrequent screen users were assessed for one week.

Researchers concluded, after collecting sleeping diaries and measuring melatonin using saliva sampling, that both intervening with glasses and abstinence aligned the sleep levels in the two groups.

So the reports are true – and in line with previous studies, such as Jordan Gaines Lewis from Pennsylvania State University’s findings in 2015, as well as advice from the Royal College of Paediatrics and Child Health.

That’s until you get to the sunglasses.

The reason why looking at blue light – or high-energy visible (HEV) light – before bed impacts on sleep is because it interferes with the body’s circadian rhythm. This regulates the sleep cycle with the hormone melatonin released late at night to help the body sleep. Blue light can interfere with the release of the hormone and interfere with sleep.

In order to stop this from happening, orange-tinted blue light-blocking glasses can reduce the exposure to your eyes and give you a better chance of getting those all-important eight hours.

It’s not just as simple as flipping on some standard Ray-Ban Aviators for some late-night scrolling before you go to bed. Neither do they stop people looking at phones as the Daily Star’s sub-deck implies with: “SNOWFLAKES should wear sunglasses to bed to stop them looking at their phones”.

A decent pair of sunglasses is primarily supposed to block out UV light from the sun, not HEV light – something to ponder on the beach and in the office this summer perhaps.

Image: Miles Cole