Sleep-deprived teenagers 'more likely to suffer depression'

Teenagers with set bedtimes are far less likely to suffer from depression or suicidal thoughts, according to a new study.

Researchers looked at data from more than 15,000 adolescents and their parents in the U.S. They found half of young adults had a set bedtime of 10pm, but a quarter were allowed to stay up past midnight and slept an average of 40 minutes less each night.