For Wu Xinyi, getting into bed each night has become an elaborate ritual: spraying lavender mist on her pillow, lighting a flower-scented aromatherapy candle, and putting on a hot compress eyeshade.

The 25-year-old says it’s the only way she can guarantee a good night’s sleep.

Wu has already taken China’s postgraduate college admission exams twice, but failed to get a high score. Now, she’s considering switching track by studying abroad or trying to enter the Chinese civil service. The uncertainty often keeps her awake.

She’s far from the only one tossing and turning at night. China has become a nation of insomniacs: More than 300 million people in the country suffer from sleep disorders, according to a report by the Chinese Sleep Research Society.

The problem is most acute among Gen Z Chinese, who struggle to catch enough z’s for a range of different reasons. Many, like Wu, blame stress. Others have physiological conditions that prevent them sleeping. A growing number say they simply enjoy staying up late.

It’s an issue that’s causing much chatter on Chinese social media. The hashtag “’90s kids become sleepy” has received 290 million views and thousands of comments on Twitter-like platform Weibo, with many young people sharing their experiences of insomnia.

“I don’t have the courage to end the day and start a new one,” read one highly upvoted comment.

Bleary-eyed millennials are also fueling the rise of a huge market for sleep aids in China. Sales of sleep apps, sleep syrups, sleep pillows, sleep candles, sleep gummies, and a bewildering variety of other sleep-related products are booming.

China’s “sleep economy” nearly doubled in size between 2015 and 2020, reaching an estimated 400 billion yuan (then $58 billion), according to a 2020 report by market researchers Leadleo. By 2030, it’s predicted to exceed 1 trillion yuan.

The fastest growth is coming from people born after 1995, according to a 2020 report on China’s online market for sleep aids produced by e-commerce giant JD.com’s research institute. Eye masks, earplugs, and night lights are among the items most commonly found in these young users’ shopping carts.

Zhang Xiaotong, a 24-year-old graduate student, has tried all sorts of products to help her deal with stress-related insomnia. She tried sleep sprays and eye masks, but found them ineffective. Now, she’s taking melatonin tablets every night — one if it’s a normal day, two if she has an exam the following morning.

The tablets appear to be doing the job. Zhang says she normally feels drowsy after taking melatonin, although sometimes, if she’s very stressed, even popping several pills isn’t enough to calm her down.

“I can’t tell if the melatonin actually works or if it’s just giving me some psychological support,” she says. “I don’t care as long as I get a good night’s sleep.

Other millennials are lulling themselves to sleep by listening to audio of people making soothing sounds, such as chewing, whispering, or knocking on a jar — a type of content designed to trigger an autonomous sensory meridian response (ASMR).

ASMR is a term first coined by Jennifer Allen, a cybersecurity researcher based in the United States. It refers to the pleasurable tingling feeling in the skull, scalp, or back caused by visual, auditory, or tactile stimulation.

ASMR videos first began appearing on Chinese social platforms in the mid-2010s before exploding in popularity in 2017. Chen Zitong, widely regarded as China’s first ASMR artist, describes her content as “the use of sound to give the audience a pleasant, comfortable feeling, and also to help them sleep.”

A 2018 study published in the Henan Medical Research journal found that more than half of people experienced ASMR-like sensations after watching ASMR videos. However, it’s still unclear what causes these responses or what physiological effects they have. So far, there is no scientific proof that ASMR content enhances sleep quality.

That hasn’t stopped ASMR winning a huge audience among young Chinese, with many saying the audio helps them combat stress, insomnia, and even depression. But the content has also become unexpectedly controversial.

In 2018, Chinese regulators began issuing strict rules targeting ASMR, arguing some creators were disguising vulgar or pornographic content as ASMR. The heads of several leading Chinese online platforms were summoned to a government meeting to discuss the problem.

Since then, many Chinese internet companies have taken a heavy-handed approach to policing ASMR content. Searching for the keyword “ASMR” on several platforms produces a string of dead links.

The clampdown has been hugely disruptive for ASMR artists like Chen Zitong. Livestreams involving ASMR have been banned outright, and platforms have even gone as far as outlawing specific sound effects.

“The heartbeat sound that many listeners liked before is also banned now, because it requires us to put the microphone on our chest to collect the sound,” says Chen. “Some people think it’s pornographic.”

But the audience for ASMR hasn’t gone away. Most ASMR artists have switched to creating videos or podcasts to get around the new rules. Users are still able to find the content as long as they know the right alternative keywords.

For Chen, China’s ASMR industry has plenty of problems — not least the large number of creators who steal her audio to use in their own content. But the future looks bright.

“Whenever a new scene emerges, there’ll be some setbacks, but that’s really just part of the development process,” says Chen.

Editors: Fu Beimeng and Dominic Morgan.

This is the first article published as part of a collaboration between Sixth Tone and IMMJ, an International Multimedia Journalism program co-run by the University of Bolton and Beijing Foreign Studies University.

(Header image: Zhang Mengyu for Sixth Tone)