Myopia, or nearsightedness, has become a global epidemic.
In the US and Europe, about 50 per cent of young adults are affected, while in parts of East Asia, rates reach nearly 90 per cent.
Blurry distant vision is the main issue, and while genes play a role, the rapid rise points to lifestyle factors. For years, experts blamed too much screen time.
But new research from the State University of New York (SUNY) College of Optometry suggests it’s not just screens. It’s how we use our eyes indoors.
WHAT REALLY HAPPENS TO OUR EYES DURING CLOSE-UP WORK?
When we read books, scroll on phones, or study on tablets in dim indoor light, our eyes focus up close.
This triggers “accommodation,” where the eye lens changes shape to sharpen the image. At the same time, the pupil constricts, not from bright light, but to help focus better.
In low light, this double effect cuts down the light reaching the retina dramatically.
Researchers, led by Jose-Manuel Alonso, MD, PhD, and doctoral student Urusha Maharjan, found that this reduced retinal light weakens certain visual signals in the eye.
Over long periods, it may trigger myopia development.
The study, published in Cell Reports, shows that people with myopia have extra pupil narrowing and eye turning during close focus, creating a cycle that worsens the problem.
WHY DOES OUTDOOR TIME HELP FIGHT MYOPIA?
Bright natural light outdoors works differently.
The pupil constricts to protect the eye, but plenty of light still hits the retina. This keeps visual pathways strong and prevents the low-light issues seen indoors.
The hypothesis explains why spending time outside slows myopia progression.
It also explains why treatments like atropine drops, which relax pupil muscles, multifocal lenses, or looking far away help by limiting excessive pupil constriction during near work.
CAN MYOPIA BE PREVENTED?
The study offers hope but isn’t the final word.
It proposes a unifying explanation for why near work in dim rooms fuels myopia, while bright light and less close focus protect against it.
Experts stress that avoiding long hours of close-up tasks in low light is a step towards prevention.
Add to that, simple steps like better room lighting, regular breaks to look far away, and more outdoor play could make a difference.
But as Alonso noted, “This is a testable idea grounded in eye physiology. More studies are needed, but it gives us fresh ways to think about prevention.”
