If you’ve ever been told that you’re on your electronic device too much, you’re just being looked out for. In China, a woman went partially blind after spending a full day playing a game on her phone.

Twenty-one year-old Wu Xiaojing was a huge fan of the popular multiplayer smartphone game “Honour of Kings.” She played the game for several hours before she suddenly lost her sight in her right eye. After being taken to several hospitals, she was diagnosed with Retinal Artery Occlusion (RAO) in her right eye. RAO is commonly found in elderly patients, and can result in permanent loss of vision. In this case it was caused by eye strain from looking at her screen for too long without a break.

Xiaojing admitted to regularly playing the game for up to eight hours without eating, drinking or using the restroom. Her parents had warned her that her eyes could become damaged if she kept on playing the game around the clock. She spent the entirety of Oct. 1, Chinese National Day, playing the game. It was only after dinner that she lost her sight and was taken to the hospital.

“If I don’t work, I usually get up around 6 a.m., have breakfast, then play until 4 p.m.,” she told Chinese state media outlet The Global Times.

The next day, she was diagnosed with RAO, which occurs when there is a blockage in one of the arteries that carries blood to the retina. According to a specialist from the Nancheng hospital where Wu was diagnosed, it was likely that she had suffered RAO after playing excessively on her phone. However, other specialists disagree. Dr. David Allamby, the medical director of an eye clinic in London, said that there was a slim chance that Wu developed RAO from playing on her phone.

“You don’t get RAO from video-related severe eye strain as is suggested here ‒ it’s most commonly evidence of some form of cardiovascular disease,” Dr. Allamby said to the Daily Mail. “The only potential link ‒and it’s slim‒ is that sometimes migraines can be a rare cause of RAO.”

“Honour of Kings” is one of the most popular smartphone games in China, and has around 200 million users. The company behind the game, Tencent, had previously restricted kids under the age of 12 to just one hour of game time per day in order to prevent addiction.

This should be a lesson for people everywhere to be cautious about how much time they’re spending on their electronics. If minimal time is spent gaming or posting on social media, situations like these can be avoided.