Quantity, content, and context of social media use may affect adolescents' sleep

"A new study published in the Journal of Adolescent Health found that checking social media often, viewing emotional or violent videos, and starting to use social media at an early age were significantly related to later bedtimes and fewer hours of sleep on school nights for early adolescents. Parental rules restricting mobile phone and online use before bed and obtaining a smartphone at a later age were associated with increased sleep duration and earlier bedtimes."