Just One Hour of Screen Time a Day Increases Myopia Risk by 21%, Study Finds

A new study has confirmed what many parents and doctors have feared—excessive screen time is taking a toll on vision. Research published in JAMA Network Open suggests that spending just one extra hour daily on screens raises the risk of myopia (nearsightedness) by 21%. And for those logging four hours or more, the risk climbs even higher.

The Growing Myopia Epidemic

Nearsightedness is no longer just an individual health issue—it’s turning into a full-blown global crisis. Often referred to as the “myopia pandemic,” the condition has been spreading at an alarming rate, especially among children and young adults.

A large-scale analysis combining data from 45 studies, covering over 335,000 participants, found a strong link between screen use and worsening vision. Researchers discovered a sigmoidal (S-shaped) dose-response curve, meaning the risk sharply rises between one and four hours of screen exposure before leveling off. Surprisingly, those who kept their screen time under an hour showed no increased risk, indicating a possible “safe zone.”

Why Are More People Developing Myopia?

With digital devices woven into daily life for education, work, and leisure, eyes are under more strain than ever before. Several factors contribute to the rapid rise in nearsightedness:

• Extended Screen Use: Staring at screens for long periods forces the eyes to focus on close objects, leading to eye strain and elongation of the eyeball—both key contributors to myopia.
• Lack of Natural Light: Studies suggest that exposure to outdoor light helps regulate eye growth and may protect against myopia.
• Poor Posture and Viewing Habits: Holding screens too close, using them in dim lighting, or maintaining poor posture adds stress to the eyes, accelerating vision deterioration.

Myopia Isn’t the Only Concern

While myopia is the main risk, excessive screen time also brings a range of other health concerns:

• Cognitive Development Issues: Too much screen exposure, especially in children, has been linked to shorter attention spans and reduced cognitive function.
• Postural Problems: Hours spent hunched over screens contribute to neck pain, spinal misalignment, and chronic headaches.
• Obesity and Metabolic Issues: Increased screen time is often associated with a sedentary lifestyle, leading to weight gain and higher risks of diabetes and cardiovascular diseases.

Protecting Eye Health in a Digital World

Despite the risks, screens are an unavoidable part of modern life. Experts suggest several strategies to mitigate the impact:

• Follow the 20-20-20 Rule: Every 20 minutes, take a 20-second break and look at something at least 20 feet away.
• Increase Outdoor Time: Spending at least two hours outside each day can help reduce eye strain and slow myopia progression.
• Optimize Screen Settings: Adjust brightness, enlarge text, and use blue light filters to reduce eye fatigue.
• Maintain a Safe Viewing Distance: Keep screens at arm’s length and avoid using devices in low lighting.
• Get Regular Eye Check-Ups: Early detection is crucial in preventing worsening vision and managing myopia effectively.

Screen Time and Myopia Risk Breakdown

The findings serve as a wake-up call for parents, educators, and policymakers. As digital reliance grows, so does the need for awareness and preventive measures. The challenge now is balancing screen use with healthy habits to ensure that today’s digital generation doesn’t pay the price with their eyesight.