Put screens away 30 minutes before bed
Reading on a tablet in the evening made young adults take about 10 minutes longer to fall asleep than reading a printed book.
The phone comes to bed with you just to set the alarm. Forty minutes later you are three videos deep, oddly more awake than when you lay down. Putting screens away half an hour before bed is one small boundary that gives your evening a quieter ending.
What it helps with
Trouble falling asleep
Reading on a tablet in the evening made young adults take about 10 minutes longer to fall asleep than reading a printed book.
Poor sleep quality
Using your phone in bed is linked to poorer sleep and more tiredness.
Morning grogginess
Young adults felt less alert the next morning after evening reading on a tablet than after reading a printed book.
Key facts
- 1In a lab study, young adults who read on an iPad before bed took longer to fall asleep than when they read a printed book.
- 2In that study, evening iPad reading delayed the rise of melatonin, a hormone tied to sleep timing, by more than an hour.
- 3Participants in the same lab study felt less alert the next morning after reading on an iPad than after reading a printed book.
- 4A meta-analysis of more than 125,000 children linked bedtime device use to about twice the odds of getting too little sleep.
- 5In a survey of adults in Belgium, using a phone in bed was linked to poorer sleep quality and more fatigue.
Why your phone keeps you up
Screens get in the way of sleep in two ways. Their bright light arrives at the hour your body expects darkness, and their content keeps your mind busy. In a survey of adults in Belgium, people who used their phone in bed tended to report poorer sleep and more tiredness the next day. The simple version of this habit is a rule you can say in a few words: the phone goes to bed first.
How evening light and scrolling get in the way
As evening goes on, your body releases melatonin, a hormone that helps signal that it is time to sleep. Bright light, especially the bluish light screens give off, can push that signal later. Then there is what you are looking at. A message, a headline or one more episode keeps you alert and quietly moves your bedtime back. Night mode cuts some of the light, but it does nothing about the next notification.
What the research found
The best-known study comes from researchers at Harvard, led by Anne-Marie Chang. Twelve young adults lived in a sleep lab and read for about four hours before bed, on an iPad for five nights and from printed books for five nights. After iPad evenings, they took about 10 minutes longer to fall asleep on average. Their melatonin rose more than an hour later, and they felt less alert the next morning.
Larger studies point the same way. A 2016 meta-analysis of more than 125,000 children found that bedtime device use was linked to about twice the odds of getting too little sleep. There are limits, though. The lab study was small and used far more screen time than a typical evening, and surveys show links, not proof that phones cause poor sleep. No study has pinned down the ideal number of screen-free minutes either. Sleep experts commonly suggest 30 to 60 minutes, so half an hour is a reasonable start, and more is fine if it suits you. Expect a modest change, such as drifting off a little sooner over a week or two.
Making it stick
Tie the habit to a fixed moment in your evening. If you go to bed at 11 p.m., your screens go down at 10:30, and a daily reminder can do the remembering for you. Charge the phone in the kitchen or hallway, out of reach of the bed. The first excuse you will hear yourself make is "but it's my alarm," and a basic alarm clock costs less than a takeaway. Keep something easy to fill the gap: a paper book, a few stretches, tomorrow's list, or a chat with whoever you live with.
On a hard day, ten screen-free minutes still counts. If you truly need to check something, do it standing in the kitchen, then leave the phone there. Most nights, the phone goes to bed first while you read or talk, and you become someone who winds down without a screen. If you still struggle to fall or stay asleep most nights for several weeks, talk to a doctor, because ongoing insomnia has effective treatments. Where in your home could your phone charge overnight, out of reach of your bed?
Action steps
- 1Set a daily reminder 30 minutes before bed. Choose your usual bedtime and set a repeating alarm for 30 minutes before it, every day of the week.
- 2Charge your phone outside the bedroom. When the reminder goes off, plug your phone in somewhere you cannot reach from bed, and use a simple alarm clock to wake up.
- 3Fill the screen-free time with one easy thing. Keep a paper book, a notebook or a stretching spot ready, and use it for the 30 minutes before you sleep.
Suggested routines
- Irregular sleep schedule
Wake up at the same time every day
Going to bed and waking at regular times is linked to a lower risk of early death, more strongly than total hours slept.
- Trouble falling asleep
Get 10 minutes of outdoor light after waking
People who get more bright light in the morning tend to fall asleep faster at night.
- Poor sleep quality
Stop drinking coffee 9 hours before bed
Studies show mistimed caffeine use reduces total sleep by about 45 minutes and deep sleep by 11.4 minutes.
References
- Chang, A.-M., et al. (2015). Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proceedings of the National Academy of Sciences, 112(4), 1232–1237. doi.org/10.1073/pnas.1418490112
- Carter, B., et al. (2016). Association between portable screen-based media device access or use and sleep outcomes: A systematic review and meta-analysis. JAMA Pediatrics, 170(12), 1202–1208. doi.org/10.1001/jamapediatrics.2016.2341
- Exelmans, L., et al. (2016). Bedtime mobile phone use and sleep in adults. Social Science & Medicine, 148, 93–101. doi.org/10.1016/j.socscimed.2015.11.037