Children should play outside to avoid having to wear glasses.
A study has found that spending just 15 minutes outdoors per day can slash the risk of short-sightedness occurring in youngsters.
Researchers at Shanghai Eye Hospital looked at almost 3,000 children - with an average age of seven - with smartwatches. to track their time outside.
None of the kids had myopia prior to the study and were given two eye tests a year apart with analysis revealing that continued outdoor activity of 15 minutes - the equivalent of at least a 2,000 lux sunlight intensity - was associated with fewer changes to the eye related to short-sightedness.
In the journal Jama Network Open, the experts said: "Future outdoor interventions for myopia prevention should include recommendations of outdoor exposure."
Researchers said the 2,000 lux level of sunlight intensity is "easily attainable" during the day – even under the shade of trees.
The team added: "A practical recommendation would be to encourage longer time outdoors as much as possible."