Myopia, or short-sightedness, is becoming a global health concern, with one in three children now struggling to see distant objects clearly.
A recent global study, published in the British Journal of Opthalmology has revealed that cases of myopia are escalating at an alarming rate — largely due to lifestyle changes, with the Covid-19 pandemic playing a significant role.
The lockdowns of 2020-2021 led to a surge in screen time and reduced outdoor activity, both of which are thought to have contributed to worsening eyesight among children.
The study, which looked at research involving more than five million children and teenagers from 50 countries across all six continents, showed the problem to be most severe in Asia, where countries like Japan and South Korea report myopia rates of 85 per cent and 73 per cent, respectively.
Even in regions like China and Russia, more than 40 per cent of children are affected. However, in countries such as Paraguay and Uganda, rates remain as low as one per cent, while the UK, Ireland, and the US hover around 15 per cent.
Myopia’s dramatic rise has been attributed to lifestyle changes, including increased screen time and reduced outdoor activity.
This rise in short-sightedness is concerning, with rates tripling between 1990 and 2023. The study also noted a particularly sharp increase following the pandemic.
The role of environment versus genetics
Genetics undoubtedly influences the development of myopia, with children inheriting a predisposition to the condition from their parents. However, environmental factors are proving to be just as significant, particularly in regions like East Asia.
In countries such as Singapore and Hong Kong, children are introduced to formal education at a very young age — often as early as two years old. This early start means that children are exposed to intensive near-vision tasks at a critical stage in their eye development.
From an early age, children are spending more time focused on digital screens, alongside their books and worksheets. These activities require sustained close-up work, which over time can lead to elongation of the eyeball — a primary cause of myopia.
The earlier children are exposed to such activities, the longer their eyes are subjected to this strain, increasing the likelihood of developing myopia at a younger age and with greater severity.
The study suggests that girls and young women are more likely to have higher rates of myopia compared to boys and young men, as they tend to spend less time outdoors both at school and at home as they grow up. Because girls typically enter puberty earlier, their growth and development start sooner, leading to the onset of short-sightedness at a younger age.
The importance of outdoor activity and natural light
Research suggests that time spent outdoors in natural light plays a crucial role in eye health, as it encourages distance vision and may help regulate eye growth. In contrast, prolonged near-vision tasks without breaks or outdoor time accelerate the progression of myopia.
When children spend more time outdoors, dopamine levels in the retina increase, which may prevent the eyeball from elongating — a key factor in the development of myopia. A study by Professor Ian Morgan and colleagues (published in Progress in Retinal and Eye Research, 2012) found that time outdoors had a protective effect against myopia, partly due to this dopamine release.
Myopia typically begins in primary school and worsens until around the age of 20, when the eye finishes growing.
Understanding this interplay between genetics, early education, screen exposure, and outdoor time is key to developing preventive measures. Interventions such as encouraging outdoor play, balancing near-vision tasks with breaks, and integrating eye health education into school systems are being explored to combat the growing myopia epidemic.
As myopia is projected to affect millions more children by 2050, it’s clear that action is needed. Our upcoming programme, Global Action for Eye Health, will delve into these emerging challenges in eye health, exploring innovations and advancements that can help address this growing issue.
By fostering awareness and promoting solutions, we aim to contribute to the global effort in preserving children and adolescents’ vision for the future.
Global Action for Eye Health – COMING SOON
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