Sleep and evening habits
Phone use and sleep: what can families learn?
Do phones affect sleep? Research suggests that specific bedtime habits deserve attention, but an association is not proof that screens cause every sleep problem.
What did the researchers examine?
Nagata and colleagues followed 9,398 US adolescents aged 11–12. They examined self-reported bedtime screen behaviours and sleep outcomes one year later, accounting for earlier sleep measures and other characteristics. This was an observational study, not an experiment that assigned different phone routines.
What did they find?
Having an internet-connected device or television in the bedroom was associated with shorter sleep duration one year later. Leaving the phone ringer on overnight was associated with shorter sleep and more reported disturbance. Texting, social media and other bedtime screen activities were also associated with less favourable sleep measures.
What does the study not prove?
It does not demonstrate that phones caused those sleep outcomes, or that removing every device will fix a sleep problem. Screen habits and sleep were assessed by reports rather than continuous experimental monitoring. The participants were US early adolescents, so the findings should not automatically be applied to every age or country.
What could you try?
Notice whether notifications interrupt the night, where the phone is kept, and whether intended bedtime is repeatedly delayed. If a change seems useful, consider silencing nonessential notifications or placing the phone away from the bed. These are optional practical ideas, not interventions proven by this particular study. Preserve access to essential calls if needed.
Explore next
Read our practical reflections on bedtime routines, and explore the free Learning to Disconnect course for ways to observe your habits and make small, sustainable changes.
Original research: Nagata et al., Journal of Adolescent Health (2024), DOI 10.1016/j.jadohealth.2024.06.006. Sources and limitations are presented so readers can distinguish study findings from our interpretation and practical suggestions.