Researchers from the Norwegian Institute have found in a new study that just an hour using the phone before going to bed increases the risk of insomnia by 59% and reduces sleep time by 24 minutes.
The study surveyed 45,202 people who answered questions about how much time they spend in front of their smartphone screen and what habits they follow before falling asleep. It is noted that the vast majority of respondents were undergraduate students aged 18 to 28. At the same time, social media activity was not a determining factor. Any use of a smartphone equally worsened the quality of sleep and increased the risk of insomnia.
«What kind of activity a person does on their phone seems to matter less than the total time spent on the screen right before bed We did not find significant differences between social media and other activities, suggesting that screen use is a key factor in sleep disruption — likely due to the time shift in which phone use delays sleep, taking time that would otherwise be spent resting», — explains Dr. Gunnhild Jonsen Hjetland from the Norwegian Institute.
Messages and interaction with the phone contribute to longer sleep, and bright light disrupts circadian rhythms responsible for activity during the day and rest at night. In the questionnaire, the study participants were asked how much time they spend on their phones just before falling asleep. Whether they watch TV shows, movies, play games, surf social media, or browse the Internet.
Initially, the researchers believed that social media was the key factor in the use of the phone before bedtime. They divided the responses of the study participants into 3 categories: those who indicated that they exclusively use social media before bed, those who did not mention social media in their responses, and those who combine their activities, including the use of social media.
In addition, participants were asked when they usually go to bed, how long it usually takes them to fall asleep and when they wake up, whether they have problems falling asleep and staying asleep, how they feel during the day, how long they can stay feeling anxiety Drowsiness in the middle of the day and problems with sleeping at least three times a week were considered signs of insomnia.
«If you are having trouble sleeping and suspect that time spent on your phone may be the cause, try to reduce your use in bed, ideally stop using it at least 30-60 minutes before bedtime», — recommends Gunnhild Jonsen Hjetland.
However, the researchers were unable to determine whether certain types of activity, including gaming or watching a specific type of content, had a significantly different impact on sleep quality Other factors, such as mental health, external influences, diet, or other factors that affect sleep quality, were not taken into account. Nor was time spent on a phone screen compared to other bedtime activities, such as reading or watching TV.
Study: people checked their phones an average of 205 times a day in 2024 — every 5 minutes, excluding sleep
The results of the study are published in the journal Frontiers in Psychiatry
