Children who frequently play outdoors have better eyesight than those who spend much of their time indoors, a new study has suggested.
According to researchers at the University of Bristol, where the new report was carried out, their study was inspired by previous research in Australia and the US, which suggested a link between the amount of time children spend in active outdoor pursuits and their chances of needing glasses later in life.
However, it was unclear whether this was due to physical activity, or to simply being outside, which the Bristol experts sought to establish.
Experts led by Dr's Cathy Williams and Jez Guggenheim followed the occurrence of short-sightedness in more than 7,000 boys and girls in the children of the 90s study at ages seven, ten, 11, 12 and 15, then and compared this to the amount of time they spent outside at age nine and how much physical activity they did at age 11.
The time spent outdoors was measured by a questionnaire filled in by the children’s parents and their physical activity was recorded objectively using an activity monitor they wore for a week at age 11.
According to the researchers, they found that children who spent more time outdoors at age eight to nine were only about half as likely to become short-sighted by the age of 15.
This UK study provides the first direct evidence, based on longitudinal data from a large number of contemporary children and teenagers in south-west England, that spending more time outdoors is associated with less myopia by age 15.
Dr Williams, from the University's School of Social and Community Medicine, said she is still not sure why being outdoors is good for children’s eyes, but given the other health benefits that experts know about, she would encourage children to spend plenty of time outside, although of parents will still need to follow advice regarding UV exposure.
"There is now a need to carry out further studies investigating how much time outside is needed to protect against short-sightedness, what age the protective effect of spending time outside is most marked and how the protective effect actually works, so that we can try and reduce the number of children who become short-sighted," the expert added.