Spending time outdoors may prevent myopia

Children who spend more time outdoors are less likely to develop short-sightedness or myopia, according to a new study.

This finding may provide the basis of a public health initiative to prevent the development of myopia in young children and adolescents.

The Sydney Myopia Study was a large school-based study of over 4,000 students aged between one and seven years, from 55 schools.

Each child underwent a comprehensive eye examination. Accurate measurement of refractive errors (myopia, hypermetropia and astigmatism) was conducted using an international standard regime of eye drops, on the lines of WHO sponsored studies.

Kathryn Rose of University of Sydney, who led the study, said "our results show that the protective effect of time spent outdoors persists even if a child is doing a lot of near work such as reading and studying.

"Television watching and using computers appears to have little effect on the development of refractive errors. Our recently published comparison of age-matched Chinese children from Sydney and Singapore showed the same trend.

"The results of this study are consistent with an American study which found that outdoor sport was protective. However our study shows that the crucial feature is being outdoors irrespective of the activity you are doing."

Prevention of myopia is important for future eye health, avoiding increased rates of cataract and glaucoma in adulthood and, in cases of high myopia, possible irreversible visual impairment.