Using a smartphone or tablet for just one hour after going to bed raises the risk of insomnia by 59%, according to new research. This finding comes from one of the largest studies conducted on screen use and sleep among university students, highlighting how our nightly digital habits may be robbing us of crucial rest.
Researchers from the Norwegian Institute of Public Health examined data from over 45,000 university students and found that each additional hour spent using screens after going to bed not only significantly increased insomnia risk but also cut sleep duration by about 24 minutes. What’s particularly notable is how consistent this effect appears to be—regardless of whether students were scrolling through social media, watching movies, or gaming.
The Digital Bedtime Crisis
Sleep problems have reached concerning levels among university students globally. The study reports that about 30% of Norwegian students sleep less than the recommended 7-9 hours per night. Even more troubling, over 20% of male students and 34% of female students report sleep issues meeting clinical criteria for insomnia, numbers that have been rising in recent years.
Smartphones have transformed our bedrooms into entertainment centers. Previous research shows that over 95% of students use screens in bed, with an average screen time after going to bed of 46 minutes. Some studies have even found that 12% of young adults engage with their smartphones during periods they’ve self-reported as sleep time.
Many sleep experts have speculated that social media might be especially harmful for sleep compared to more passive activities like watching television. The reasoning seems logical – social media platforms are designed to keep users engaged through interactions, notifications, and endless scrolling features that make it difficult to disconnect. Plus, the social obligations and fear of missing out associated with platforms like Instagram and TikTok might make users more reluctant to put their devices away at bedtime.
Surprising Findings Challenge Common Beliefs
Researchers divided participants into three groups: those who exclusively used social media in bed (about 15% of the sample), those who used social media combined with other screen activities (69%), and those who engaged in non-social media screen activities only (15%).
Contrary to expectations, students who exclusively used social media in bed reported fewer insomnia symptoms and longer sleep duration compared to the other groups. The non-social media group experienced the highest rates of insomnia and shortest sleep duration, while those mixing social media with other activities were intermediate.
This unexpected outcome challenges the notion that social media is uniquely harmful to sleep. Instead, the research points to the total time spent on screens in bed, regardless of the specific activity, as the strongest predictor of sleep problems. Each additional hour of screen time after going to bed was consistently associated with poorer sleep outcomes across all three groups.
Why might social media-only users sleep better? Researchers propose that exclusively using social media might reflect a preference for socializing and maintaining connections with others, which generally protects against sleep problems. Being socially engaged has been linked to better sleep in numerous studies.
Alternatively, those experiencing the most sleep difficulties might deliberately avoid social media before bed, instead turning to activities like watching movies or listening to music as sleep aids. Many people with insomnia use screen-based activities to distract themselves from negative thoughts or anxiety that prevent sleep.
What This Means For Your Sleep
The study, published in Frontiers in Psychiatry, reveals how screens affect sleep through several pathways: direct displacement (screen time replacing sleep time), light exposure (suppressing melatonin production), increased mental arousal (making it harder to fall asleep), and sleep interruption (notifications disturbing sleep).
The findings from this study largely support the displacement hypothesis. If increased arousal from interactive content were the main factor, we would expect to see different associations between sleep and various screen activities. Instead, the consistent relationship between screen time and sleep problems across activity types indicates that simply spending time on screens—time that could otherwise be spent sleeping—may be the most important factor.
For university students already struggling with academic pressure, social adjustment, and mental health challenges, poor sleep represents an additional burden with potentially serious consequences. Sleep deprivation impairs attention, memory, and other cognitive functions crucial for academic success.
Non-screen users had 24% lower odds of reporting insomnia symptoms, confirming that keeping devices out of the bedroom is a worthwhile sleep hygiene practice. Even if it’s not a complete solution to sleep difficulties, it represents a behavior that could meaningfully improve sleep for many young adults.
“If you struggle with sleep and suspect that screen time may be a factor, try to reduce screen use in bed, ideally stopping at least 30–60 minutes before sleep,” says lead author, Dr. Gunnhild Johnsen Hjetland, in a statement. “If you do use screens, consider disabling notifications to minimize disruptions during the night.”
The next time you’re tempted to bring your phone to bed “just to check a few things,” remember the Norwegian students’ experience: each hour spent on that screen, regardless of what you’re doing, might cost you 24 minutes of precious sleep and significantly increase your chances of developing insomnia. Given what we know about the essential role of sleep in physical and mental health, learning, and overall wellbeing, that’s a trade-off worth reconsidering.
Source : https://studyfinds.org/screen-time-bed-insomnia-risk/