Children and teenagers in Beijing get less sleep than those in other parts of the country, putting them at a higher risk of physical and mental health problems, a report has warned.
Residents snooze 7.6 hours a night on average, but about 25 per cent of the city population regularly gets insufficient sleep, according to the China sleep index released by the capital's Health and Family Planning Commission.
At least 30 per cent survive on fewer than 6.5 hours a night, the report said.
In particular, it said, children and adolescents living in the capital get less sleep than their peers elsewhere because of the large amounts of homework, excessive use of electronic devices and poor sleeping patterns.
Primary school student Li Li said she goes to bed each day around midnight after finishing her homework and playing mobile games for a few hours.
"I play online games together with many of my classmates after we finish our studies," the 10-year-old said. "It's a way of relaxing after studying all day. Plus, my parents also play mobile games after dinner."
Health experts have warned that long-term sleep problems and insomnia can increase the risk of cardiovascular disease, anxiety and depression.
A report on national sleeping patterns released in November by Huawei Sports and Healthcare said the major problems in China are insufficient deep sleep, disruptive dreams and frequently waking up.
More than 60 per cent of Chinese don't get enough deep sleep, a stage of nonrapid eye movement also known as slow-wave sleep, the findings show.
According to the American Sleep Association, slow-wave sleep gives the brain time to restore itself from daily activities, which is important for health.
Gao Jian, a 30-year-old banker in Beijing, said he never gets to bed before midnight and often finds it difficult to fall asleep when he is handling an important project.
"It seems almost everyone who works in finance has a sleeping problem because our work is so stressful," he said. "It'd be big news if someone on my team was sleeping well."
The commission's report urges people to take sleeping problems seriously: "When necessary, those who suffer from sustained problems should go to a hospital or medical care centre for help."