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is best - but catching up on shuteye at weekends can lower the risk of symptoms of depression, say American scientists.

Researchers from the and the found that sleeping in on Saturday or a Sunday to catch up on zeds lost during the week may be good for adolescents’ mental well-being.

The team found that a group of young people, age 16 to 24, who caught up on sleep on the weekend had a 41% lower risk for symptoms of depression than a group who didn’t.

They say their findings, published in the , highlight the important link between sleep and mental health in teenagers.

The research team say teenagers face sleep challenges and heightened risk for symptoms of depression, but that age group has rarely been included in studies of weekend catch-up sleep.

They said the findings provide the first glimpse into weekend catch-up sleep for typical American teenagers as previous studies focused on school-age teens in China and Korea.

The researchers explained that it’s common for teens in the U.S. to rack up a sleep deficit during the week because of everything competing for their time and attention such as school, social life, extracurricular activities, and often an after-school job.

Co-author Professor Melynda Casement said: “ and clinicians have long recommended that adolescents get eight to 10 hours of sleep at a regular time every day of the week, but that’s just not practical for a lot of adolescents, or people generally,�

The research team emphasized getting the recommended eight to 10 hours of sleep each night is still ideal.

But they say if that’s not possible, then sleeping in on weekends may help lower the risk of symptoms of depression.

Casement, a licensed psychologist at the , said: “It’s normal for teens to be night owls, so let them catch up on sleep on weekends if they can’t get enough sleep during the week because that’s likely to be somewhat protective."

The study participants, aged 16- to 24-year-old, reported their bedtimes and wake-up times during the week and weekend, which the researchers used to calculate their weekend catch-up sleep, the difference between the day and the average sleep per weekday.

The participants also reported how they were feeling and were counted as having symptoms of depression when they reported feeling sad or depressed daily.

Sleep cycles - known as circadian rhythms - start shifting in adolescence, making it harder for most as early as they did when they were younger.

Casement said: “Instead of being a morning lark you’re going to become more of a night owl.

“And sleep onset keeps progressively delaying in adolescence until age 18 to 20.

"After that, you start becoming more morning larkish again.�

The typical sleep cycle for around 11pm, and wake at 8am.

But that conflicts with early start times at many American high schools.

As a result, many sleep scientists and health care providers support the public health campaign to start schools later.

Casement says depression is one of the leading causes of disability among 16- to 24-year-olds, where "disability" is defined broadly as impairment of daily functioning, such as calling in sick or being late to work.

She added: “It makes that age range of particular interest in trying to understand risk factors for depression and how those might relate to delivery of interventions."