How much sleep do teenagers need?

In a new study published in Child Development, Andrew J Fuligni and colleagues examined whether there is an “optimal” amount of sleep for peak levels of academic achievement and mental health in teenagers.

A total of 421 pupils (mean age = 15.03 years) with Mexican-American backgrounds from the 9th and 10th grades (Years 10 and 11) of two high schools in the Los Angeles area reported the amount of sleep they had every night for two weeks. Official school records were obtained at the end of the academic year to measure academic achievement. The Youth Self-Report form of the Child Behavior Checklist was used as a measure of mental health. A year later, 80% repeated the same process and a second wave of data was collected.

Pupils who averaged 8.75 – 9 hours of sleep per school night demonstrated peak levels of mental health, whereas those who averaged 7 – 7.5 hours of sleep per night had the highest levels of academic achievement (see also an earlier study reported in Best Evidence in Brief).

While the results showed that the “optimal” amount of sleep needed is different for the two developmental outcomes, the researchers note that reducing sleep for the sake of academic performance may result in a greater decline in mental health than in the decline in academic performance from increasing sleep for the sake of mental health.

Source: Adolescent sleep duration, variability, and peak levels of achievement and mental health (January 2017), Child Development DOI: 10.1111/cdev.12729