The Science of Myopia

Global myopia rates are rising rapidly. In China, over 50% of teenagers are nearsighted. Understanding how myopia works is the first step in protecting your vision.

How Does the Eye See?

Light enters the eye and is refracted by the cornea and lens to form a clear image on the retina. If the eyeball is too long, light focuses in front of the retina instead of on it, making distant objects blurry. That's myopia.

Why Does Myopia Happen?

Genetics — Children of nearsighted parents are more likely to develop myopia, but genetics is only part of the story.

Environment — This is the main driver of the myopia epidemic:

• Extended close-up work (reading, screens)
• Lack of outdoor time (natural light triggers dopamine release in the retina, which helps control eyeball growth)
• Insufficient lighting during visual tasks

Can Myopia Be Prevented?

While it can't be fully prevented, risk can be reduced:

1. More outdoor time — At least 2 hours daily. This is the strongest evidence-based prevention method
2. Limit close-up screen time — Follow the 20-20-20 rule
3. Maintain proper distance — At least 30cm for reading, 50cm for screens
4. Ensure good lighting — Make sure your environment is well-lit during reading and study

Can Vision Training Cure Myopia?

No. Established myopia (elongated eyeball) is a structural change that exercise cannot reverse. But vision training can relieve eye strain, improve visual habits, and help you take better care of your eyes in daily life.