The difference in sleep schedules between school days and weekends has been dubbed “social jet lag.” On Saturdays and Sundays, teenagers may sleep in and wake up much later than usual, causing their bodies to fall into a different rhythm, like a time zone difference.

This misalignment can be confused with the natural delay in melatonin production during adolescence, a biological shift in the internal clock that causes young people to fall asleep later. However, in this case, it is more a matter of a discrepancy between sleep schedules during the week and on weekends, which forces the body to readjust repeatedly, week after week. Poor sleep quality, when repeated during the transition to puberty, can affect the development of neural systems and contribute to the onset of disorders such as anxiety and depression. Poorer sleep quality—as indicated by a study by Bradley Brosnan and colleagues—has been linked to increased irritability, attention and health problems, and, consequently, poorer cognitive and academic performance.

A recent study by Illingworth et al. analyzed data from 19,760 participants and found that English children and adolescents aged 9 to 18 had, on average, a social jet lag of 1 hour and 53 minutes. The discrepancy in sleep schedules was associated with age—and certain daily routines and the use of electronic devices increased the mismatch. Furthermore, according to this study, social jet lag tends to increase as young people progress through adolescence: it peaks at age 15 (with an average difference of approximately 35 minutes during those years), but appears to decrease between ages 16 and 18, when sleep schedules become more regular again.

What can we do to ensure that young people get a good night’s sleep?

Here are three simple tips:

  • Establish a consistent sleep routine, both on weekdays and weekends, using, for example, a sleep calculator.
  • Set limits on the use of electronic devices (such as cell phones, computers, and video game consoles) before bedtime.
  • Talk to them about the characteristics of sleep and how our biological clock works (for example, how the body responds to natural and artificial light).
March 13th, 2026 ED_ON Author: Joana Rato