You know how, in the evening, you spend a lot of time staring at your phone? And how you often carry on scrolling in bed?

Well, that daily habit may be having a profoundly negative impact on your sleep and mental health.

A recent study has shown that avoiding phone use for just 30 minutes before bedtime increases sleep quantity and quality, and improves mood and cognitive function.

Let’s get into it.

Thirty-eight participants – with already poor sleep quality and a habit of bedtime phone use – were randomised into two groups for four weeks.

The intervention group were told to stop using their phones 30 minutes before bed, and to make sure the instructions were followed, their phones were set to display a grey screen with no access to apps 30 minutes before their usual bedtime.

The control group were told to continue their evening routine as normal.

And what happened was remarkable.

From just 30 minutes of phone abstinence before bed for four weeks:

• Sleep latency (the time it took to fall asleep) decreased
• Sleep duration (the time asleep) increased
• Sleep quality – as measured by the Pittsburgh Sleep Quality Index – improved
• Mood improved (positive feelings increased, negative feelings decreased)
• Reaction time and accuracy both improved

It’s safe to assume that these effects were partly due to a reduction in evening blue light exposure, which we know is detrimental to sleep. But the study suggests that there is something else at play here: arousal. The intervention group had reduced levels of pre-sleep mental and physiological arousal. In other words, they were calmer and more relaxed before bed.

So, should you stop using your phone late in the evening? Well, that’s up to you. As we’ve seen here, even 30 minutes of phone abstinence before bedtime is effective for improving sleep and mental health.

If you want to give it a go, remember that it’s going to take more than simply saying you’ll do it. The apps we spend the most time on – such as WhatsApp, Instagram, and Twitter – are habit forming. They’re designed that way because holding your attention is how they make money.

How do you stop scrolling on your phone when you should be winding down for bed? Here are a few ideas:

One-time actions

• Switch off notifications: Notifications prompt you to pick up your phone and start scrolling and engaging. That’s why the social media companies want you to keep notifications switched on. Turn them all off and take back control of your evening (and the rest of your day)
• Use ‘Downtime’: On an iPhone go into Settings > Screen Time > Downtime. Switch Downtime on; set ‘From’ to 30-60 minutes before your usual bedtime; and set ‘To’ to your usual wake time. Then go to Screen Time > Always Allowed, and exclude all apps other than Phone. This means that you can’t access the habit-forming apps during bedtime, but you can make and receive phone calls

Small daily habits

• Put your phone in Aeroplane Mode (yes, I know it’s Airplane Mode but I can’t bring myself to spell it like that): Flick the switch an hour or so before bed. If you get the urge to pick up your phone and scroll you can still do that, but you’ll have to go into Settings and turn Aeroplane Mode off. This might not seem like much, but it should be enough friction to stop you doing it more often than not. For a bigger effort barrier, try turning your phone off completely
• Put your phone out of sight and reach: Take away the prompt by putting your phone in a room you don’t use in the evening. This also introduces friction to make accessing your phone more difficult if you get the scrolling urge. The advantage of this one is that people can still get through to you on the phone (as long as you can hear it ringing)

Have a go and see what happens.

But remember, getting better sleep is the accumulation of dozens of different one-off actions and daily habits. Start with reducing your evening screen time and build from there.