Guide · children
Screen time and children’s eyes: what the evidence actually says
Screens don’t damage a child’s eyes. What they do is take the place of the one thing that protects them. That’s a different problem, and an easier one to solve.
What screens don’t do
There’s no good evidence that the light from a screen harms a child’s eyes, or that blue light does. Tired eyes after a long session are real — children blink less staring at a screen, and the tear film dries — but it’s temporary.
What they do
Two things. They’re near work, and lots of near work in childhood is associated with short sight developing and progressing. They keep children indoors, and time outdoors in daylight is the best-evidenced protection against short sight there is — the studies point to about two hours a day. A child on a tablet on the sofa is losing both ways.
The three rules
- Outside for two hours a day. Not sport; just daylight. A walk to school counts.
- Arm’s length, and breaks. The screen further away than a book would be, and a look out of the window every twenty minutes.
- A yearly eye test. Free under sixteen, and the only way to know whether a prescription has started to move. What it involves →
If it’s already moving
Short sight that goes up every year can be slowed. Myopia management →
The short version
- Screens don’t damage eyes; they displace daylight and add near work
- Two hours outdoors a day is the best-evidenced protection
- Arm’s length, breaks, and a yearly free test
- Rising short sight can be slowed