The late-night screen habit that steals your sleep

Imagine the scene: it’s late at night, you’re tucked into bed, and you tell yourself you’ll just scroll for “five more minutes.” An hour later, you’re still glued to your screen, whether you’re chatting on Instagram, watching TikToks, or streaming a show you’ve seen three times already. Most of us know this scene all too well, and many have heard that screens at bedtime are “bad for sleep.” But does it matter what you’re doing on the screen? Is social media uniquely harmful, or are all nighttime screen habits equally guilty?

A team of researchers from Norway, Australia, and Sweden decided to find out. Led by Gunnhild Johnsen Hjetland at the Norwegian Institute of Public Health, with colleagues Jens Christoffer Skogen, Mari Hysing, Michael Gradisar, and Børge Sivertsen, they dug into a massive national dataset of over 45,000 university students. Their study, published in Frontiers in Psychiatry, is one of the largest to compare different types of screen use at bedtime and their relationship to sleep.

The starting point was a reality check: most young adults simply aren’t getting enough sleep. Recommendations say 7–9 hours a night is healthy, but 30% of Norwegian students sleep fewer than 7 hours, and insomnia symptoms are common, especially among women. Past research has linked screens to shorter sleep and more restless nights, often focusing on adolescents. The problem is, almost all these studies lump “screen time” together, leaving us with a vague idea that screens are bad, but not knowing if certain activities, like social media, are worse than others.

In this new study, students reported whether they used screens in bed after “lights out” and, if so, what they were doing. Options ranged from watching movies, gaming, and listening to podcasts to reading study materials or scrolling social media. This let the team divide people into three groups: “Social Media Only,” “Social Media + Other Activities,” and “Non-Social Media” (for those who watched, listened, read, or gamed without social media).

The headline result? Every extra hour of screen use in bed was linked to a 59% higher chance of insomnia symptoms and about 24 minutes less sleep per night. That’s across the board, whether the activity was social media, gaming, or a Netflix binge. The type of activity didn’t change the strength of the link between screen time and poorer sleep.

But here’s the twist: when the researchers looked at the groups independently of screen time, a curious pattern emerged. The “Social Media Only” group actually had the best sleep on average, fewer insomnia symptoms, and slightly longer sleep, while the “Non-Social Media” group had the worst. The mixed-activity group fell in between. It’s the opposite of what many would expect given social media’s bad reputation.

Why might this be? The authors offer a few theories. One is that social media use, despite its potential for distraction, often involves connection and socializing, factors that can protect against poor sleep. Another is that people who avoid social media at night might be doing so because they already have sleep problems and are experimenting with strategies to improve rest. Or, perhaps, non-social media activities like late-night movie marathons or gaming are more likely to serve as “sleep aids” for people struggling to nod off, making their insomnia appear worse.

There’s also the “displacement hypothesis,” which says that screens harm sleep mainly by replacing it. You go to bed at midnight but spend the first 45 minutes on your phone, so you fall asleep later and sleep less. If displacement is the main culprit, it makes sense that the type of content matters less than the fact that you’re delaying sleep.

The study has its caveats. It’s based on self-reports, so students might underestimate (or overestimate) their actual screen time and sleep. It’s also a snapshot in time, so we can’t say screens cause poor sleep, it could be that poor sleepers use screens more. And the “activity” categories are broad. For example, “gaming” and “listening to a podcast” are lumped together in the non-social media group, even though those experiences are very different in terms of stimulation and potential sleep disruption.

Still, the sheer size of the dataset and the focus on young adults make this work stand out. The findings suggest that public health advice might need a slight shift. Rather than singling out social media as the bedtime villain, it may be more effective to simply encourage less screen time overall before and after lights out, regardless of what’s on the screen. That could mean setting a “phone down” time, charging devices outside the bedroom, or replacing late-night scrolling with non-screen wind-down habits.

Perhaps the most human part of this study is what it says about how we use technology in bed. Some of us are connecting with friends; others are distracting ourselves from anxious thoughts; some are just enjoying a good series. The tricky part is that all of these uses—helpful or not—can eat into the hours we have for sleep. As Hjetland and her colleagues put it, screens in bed are now “commonplace” for over 95% of students, so the question isn’t just whether to use them, but how to manage them in ways that protect our rest.

The takeaway? If you want better sleep, the clock matters more than the app. It’s less about quitting Instagram and more about making sure your “just five more minutes” doesn’t turn into a late-night time warp. After all, those 24 minutes lost per hour of screen time add up fast, and no amount of morning coffee will give them back.

If you want to learn more, the original article titled "How and when screens are used: comparing different screen activities and sleep in Norwegian university students" is available on Frontiers in Psychiatry at https://doi.org/10.3389/fpsyt.2025.1548273