Today, myopia is no longer just a vision peculiarity, but a global trend. According to forecasts, by the middle of the century every second person on the planet may be short-sighted.
For a long time, screens were considered the main culprit. However, scientists at the College of Optometry of the State University of New York have offered a more precise explanation. The key role is played not by technology itself, but by the combination of prolonged focus at close range and insufficient lighting.
When working on a laptop or phone in dim light, the eye is in a state of strained focus. The pupil narrows to see nearby objects clearly, and the retina receives less light. This is what triggers changes in the shape of the eye, which over time lead to myopia.
In Scandinavia, myopia is found in 13–25% of the population, while in East Asia it reaches up to 90%. One explanation is simple: northern schoolchildren spend more time outdoors. Children go outside for 2–3 hours a day even in bad weather. In Singapore, South Korea and China, schoolchildren spend up to 10–12 hours a day studying. Singapore, where myopia has risen from 10% to 90% over 50 years, is cited as an example of how the prevalence of myopia can rise sharply in just a few generations.
Some Asian countries have introduced preventive measures. In Guangzhou, 40 minutes of outdoor time were added to the schedules of 950,000 schoolchildren, and a few years later the risk of developing myopia fell by 20–30%. Taiwan’s Tian-Tian 120 program recommends that children aged 5–7 spend at least 120 minutes outdoors each day, and within a year the incidence of myopia fell by almost half.
The practical conclusions sound surprisingly simple. What matters is not only limiting screen time, but also the conditions in which we read and work. Current ophthalmological recommendations come down to a simple 20-20-2 rule: every 20 minutes of close work, look into the distance for at least 20 seconds, and spend 2 hours a day outdoors.
So go for a walk, friends!
