It's a slightly awkward article for a social network to publish. LatePals exists for people who are awake late, and plenty of you open it from bed. But we'd rather you came back tomorrow rested than stayed up until four because a feed kept pulling you along. So here's an honest look at what screens do to sleep, and what to do about it.
Blue light: real, but overrated
The usual story goes like this. Screens give off blue light, blue light suppresses melatonin (the hormone that tells your body it's night), so screens ruin sleep. The first two parts are true. In lab studies, bright light, especially in the blue part of the spectrum, delays the evening rise in melatonin and can push your body clock later.
The catch is the dose. Most of those studies use light that is brighter, or lasts longer, than a phone held at a normal distance with the brightness turned down. In everyday life, the light from a phone is a fairly small signal compared with ceiling lights, a bright bathroom or a big TV. Night-mode filters aren't the cure-all they're marketed as either. One 2021 study of young adults found that using a phone's night-shift setting on its own didn't produce measurably better sleep than not using it.
So dimming your screen and turning on night mode is fine. It just probably isn't the thing that matters most.
What actually keeps you up
1. Your brain is switched on
A heated comment thread, a group chat that won't stop, a video that ends on a cliffhanger. All of these raise alertness. Sleep comes easily when your mind is idling, and it is hard when your mind is busy. What you're looking at matters more than the colour of the light it comes in.
2. It quietly steals time
Researchers call it displacement. "Five more minutes" turns into forty, and the time comes straight out of your sleep. This is the most consistent finding in the research on screens and sleep: people who use devices in bed tend to fall asleep later and sleep less overall.
3. Notifications wake you up
A buzz at 2 a.m. doesn't have to fully wake you to fragment your sleep. Brief arousals that you don't even remember can leave you feeling less refreshed.
Fixes that work (and don't require throwing your phone in a lake)
- Schedule Do Not Disturb. Both Android and iPhone let you set it to switch on automatically, with exceptions for the people who genuinely need to reach you. It's the single highest-value change.
- Pick a "last scroll" time. Not a bedtime: a time after which you stop starting new things. Finishing a conversation is fine. Opening a new one isn't.
- Charge it out of reach. If the phone is across the room, picking it up becomes a decision instead of a reflex. A cheap alarm clock removes the "but it's my alarm" excuse.
- Switch to low-stakes content. If you do use your phone late, choose things that calm you down. A podcast, a familiar show or an audiobook with the screen off beats arguing in comments.
- Lower the overall light. Dim the room as well as the phone in the last hour. Lamps instead of ceiling lights make a bigger difference than any screen filter.
- Get daylight in the morning. Morning light helps set your body clock earlier, which makes it easier to feel sleepy at a sensible time in the evening.
When it isn't the phone
Sometimes the phone gets blamed for a problem it didn't cause. If you're lying awake most nights regardless of what you do, or you're exhausted during the day, the screen may just be what you reach for because you can't sleep. That's worth raising with a doctor. Persistent insomnia is common and treatable, and the first-line treatment, cognitive behavioural therapy for insomnia (CBT-I), works well.
This article is general information, not medical advice. If you have ongoing sleep problems, talk to a doctor or other qualified health professional.
