Quebec research finds screens contributes to increase in myopia cases among young people

Prolonged exposure to screens is harmful to the eyes, but it doesn’t seem so easy to give them up to protect your eye health. The Association of Ophthalmologists of Quebec has noted an increase in cases of myopia among young people, and screens are a contributing factor. 

The explosion of myopia cases worldwide worries Isabelle Laliberté, pediatric ophthalmologist, who came to share her experience with elected officials on Thursday, as part of the Special Commission on the impacts of screens and social networks on the health and development of young people. 

The World Health Organization (WHO) estimates that by 2050, between 40 and 50 per cent of the world’s population will be myopic, compared to around 20 to 30 per cent today. 

“This is the beginning of an epidemic,” said Dr. Salim Lahoud, president of the Association of Ophthalmologists of Quebec, in committee. He notes that cases are constantly increasing in Quebec.

A myopic person has an eye that grows too much and becomes too long, which means that they cannot see well from a distance, explains Dr. Laliberté. 

Some 3,000 studies have demonstrated a correlation between screen use and an increase in the prevalence of myopia, the specialist argued. “But that doesn’t prove a direct causal link. Myopia isn’t just due to screens, there’s genetics too and several other causes,” she qualified. 

The fact remains that exposure to screens affects vision. Dr. Laliberté told parliamentarians that 70 per cent of young people who use a screen for more than four hours a day—which is common among young people—report symptoms such as blurred vision, eye pain and headaches. “It’s called digital visual fatigue and it’s the screens that do it,” explained the pediatric ophthalmologist. 

Dr. Lahoud believes that there is a lack of awareness among patients regarding the negative effects of screens on the eyes. “We need to work on this,” he says. 

Simple preventive solutions 

Distance plays a role in distance vision loss. Young people look at their screens from approximately 30 centimeters away, which causes hyperstimulation of the eye muscles. “The accommodation muscles are constantly working and it is this prolonged overload that can cause the eye to elongate,” explains Dr. Laliberté. 

Lack of natural light also contributes to the observed increase in myopia. “Studies have shown that insufficient time spent outdoors during childhood contributes significantly to the development of myopia,” adds Dr. Laliberté. She cited a study that indicates that children who use screens for more than three hours a day have a 2.5 times higher risk of developing myopia.

Screens also have consequences on the quality and duration of sleep. “Children and adolescents who use screens an hour or more before bedtime sleep on average one to two hours less per night,” says Dr. Laliberté. 

Screens also affect REM sleep, a phase essential for memory consolidation and emotional management. 

In addition, the blue light emitted by screens stimulates the retina, which will suppress the production of melatonin, an important hormone in the sleep-wake cycle. 

Fortunately, there are preventative solutions, including avoiding looking at a screen before going to sleep. Removing your cell phone from the bedroom goes a long way in achieving this goal. 

Ophthalmologists recommend at least two hours of outdoor time per day for young people, as natural light prevents excessive eye growth, and therefore reduces the risk of myopia in children. They also suggest that parents limit screen time to two hours per day for children under 12, with frequent breaks.

“Even if there are treatments, these are high costs for patients and for society. While prevention is quite easy, you just have to go play outside […] and that will greatly reduce the progression [of cases of myopia] that we currently have,” argued Dr. Lahoud. 

While the symptoms of myopia can be corrected with glasses or contact lenses, this carries other risks. Young people who are very myopic are at greater risk of having a retinal detachment in adulthood with permanent visual loss. 

The Canadian Press’ health content is funded through a partnership with the Canadian Medical Association. Editorial choices are solely the responsibility of The Canadian Press.

–This report by La Presse Canadienne was translated by CityNews