(CNN) — More than a third of children around the world were nearsighted in 2023, and this proportion will rise to almost 40% in 2050, according to new research.
Nearsightedness, or myopia, refers to when closer objects are clear, but distant objects are blurry.
There has been a significant rise in the prevalence of myopia among children and adolescents in the past 30 years – from 24% in 1990 to almost 36% in 2023 – according to the paper, published in the British Journal of Ophthalmology on Tuesday.
Researchers from Sun Yat-sen University in Guangzhou, China, reached their findings by analysing the results of 276 studies involving more than 5.4 million children and adolescents in 50 countries across all six continents.
While this increase has largely been gradual, there was a notable spike after the Covid-19 pandemic, say the researchers, who also noted regional disparities.
“Myopia has emerged as a major public health concern nowadays, with striking evidence existing for rapid increases in its prevalence, especially for Southeast Asian countries such as Singapore, China and Taiwan,” according to the paper, which found that East Asian children had the highest rate of nearsightedness, at 35% – more than twice the rate of their White peers.
This could be due in part to the fact that East Asian children start formal education at the age of 2 or 3, earlier than kids in other regions, the researchers say.
Japan topped the list, with 86% of children nearsighted.
South Korea had the second-highest rate, at 74%.
Globally, children in urban areas have higher rates of myopia than those in rural areas, while girls are slightly more likely to suffer from the condition than boys.
The researchers emphasised that younger children were more vulnerable to environmental factors than adults, saying “this is particularly significant for preschool children, as they are in a critical period of visual development characterised by high plasticity.”
Looking ahead, researchers forecast that the prevalence of myopia will continue to increase among children and adolescents, reaching 36.6% in 2040 and 39.8% in 2050.
There are things parents can encourage their children can do to protect their vision, though.
The researchers recommend that young people “develop the habit of regularly practising eye-protective measures.”
“Students should also increase the amount of time spent on physical activity and decrease the time spent on non-active activities such as watching television and videos, playing computer games, and surfing the internet,” the researchers say, calling on officials to reduce the burden of homework and tutoring on students, as well as promoting eye exams, early detection and treatment.
These recommendations were echoed by Dr. Benjamin Botsford, an ophthalmologist at UMass Chan Medical School, in a piece for The Conversation in June.
Progression of nearsightedness in children can be slowed by taking breaks and avoiding hour after hour on the phone or computer, he wrote.
Limiting up-close reading time outside of school — screen time or otherwise — may help slow the progression of nearsightedness in children, he added.
Prolonged screen time can cause eye strain and dryness. Botsford suggests following the “20-20-20 rule.”
“Take 20-second breaks every 20 minutes to look 20 feet away from your device. Focus on relaxing the eyes and blinking. The occasional use of artificial tears, which can be bought over the counter at drugstores, may help with dry eye,” he said.
Botsford also advises that spending time outdoors is good for your eyes, saying “it has been correlated with a reduced incidence of nearsightedness in childhood.”