Nearly eight in 10 US high school students were not getting the recommended amount of sleep in 2023, according to a study highlighting a worsening trend in adolescent sleep.

The analysis, published in the Journal of the American Medical Association, found that 77% of high school students reported sleeping less than the recommended eight to 10 hours a night. That was up from 69% in 2007. The proportion getting five hours or less rose particularly sharply, from 16% to 23%.

The findings are based on the long-running Youth Risk Behaviour Survey, which tracks health-related behaviours among US high school students.

How Much Sleep Do Teenagers Need?

The American Academy of Sleep Medicine recommends that adolescents aged 13 to 18 get eight to 10 hours of sleep every night.

Sleep is particularly important during adolescence, when the brain and body are still developing. Adequate sleep supports physical and mental health, attention, learning, behaviour, and safety, according to the US Centers for Disease Control and Prevention (CDC).

Yet CDC data show that only about one in four US high school students got at least eight hours of sleep on an average school night in 2023.

Read more

What Happens When Teens Don't Get Enough Sleep?

Regularly sleeping too little can make it harder for teenagers to concentrate, learn, and regulate their emotions.

Sleep deprivation has also been associated with poorer mental health and a higher risk of injuries and other health problems. The CDC notes that insufficient sleep among children and adolescents is linked to problems including obesity, type 2 diabetes, poor mental health, attention difficulties, and behavioural problems.

There can also be immediate safety concerns. Too little sleep can impair attention and increase risky behaviours, including unsafe driving among teenagers.

Why Are So Many Teens Sleep-Deprived?

It may not simply be a matter of teenagers choosing to stay up late. Puberty naturally shifts the adolescent body clock later.

Changes in the timing of melatonin release can make it harder for teenagers to fall asleep early, while they may still need to wake up early for school. Researchers estimate that this shift can delay sleep and wake times by as much as two hours.

School schedules can therefore compound the problem. Early start times may require teenagers to wake before their biological clocks are ready, reducing the amount of sleep they can get on school nights.

The recent study found that the increase in insufficient sleep was not limited to teenagers already experiencing behavioural or mental health risk factors. Researchers suggested that broader structural factors, including school schedules, may therefore be contributing to the trend.

How Can Parents Help Teens Sleep More?

Parents can encourage consistent bedtimes and wake times, including at weekends, and establish boundaries around phones and other digital devices at night.

The CDC recommends considering a rule that devices are put away at least one hour before bedtime and, where possible, keeping phones outside the bedroom overnight.

Schools may also have a role. Research cited by Science News found that delaying school start times can increase sleep duration, while one study found fewer symptoms of depression among students whose schools moved their first bell later.

For parents, persistent difficulty sleeping, excessive daytime sleepiness or significant changes in mood and behaviour may warrant a conversation with a healthcare professional.

Read more