It appears that the incidence of children who need glasses of short-sightedness (myopia) has been rising. This has been quite a consistent finding across the globe. Today’s kids spend more time indoor than outdoor especially post pandemic in this current time.
With winter approaching; it is important to allow extra outdoor time when possible to reduce the risk of childhood myopia. Depending where we live; incidence of myopia in children is higher in different part of the world. In the USA (and similar in Australia) by adulthood we have 1 out of 3 people with myopia. In parts of Asia where the children spend most time indoor the myopia incidence is much higher (up to 90%). In the past; average age of children developing myopia is 12 or 13 years of age however now children as young as 5 or 6 have been getting onset of myopia. When children started myopia in younger age; generally they progress in much greater rate that is possesses much greater risks of eye diseases when they are older.
Many researches showed that children with extended time reading or concentrating at close up objects (including screen time) develop myopia in younger age and the progression is faster. Other researches linked the myopia in children to genetic influence and outdoor time. Newer studies have backed up the outdoor time to reduce risk of myopia in children. This outdoor time factor has been significantly shown to reduce risk of myopia however the real reason why this is the case is unknown; whether our children’s eyes focus at longer distance objects outside or whether they are exposed to greater amount of light.
It is important for our children even during winter to spend at least 2 hours outdoor (when possible) as the first line of prevention of myopia. A new study from the University of Canberra also showed that once a light reaches certain intensity (outdoor light certainly emits higher intensity measured in unit of lux), a chemical of dopamine is released within the eye and it stops the elongation at the back of the eye. On the days that it is not possible; limiting screen time and near tasks (max 2 hours a day) can be beneficial as well as taking regular breaks while doing near work (20-20 rule; every 20 minutes take 20 seconds rest).
Sonya Wijaya (B. Optom. Ther. Endorsed/ PG. Spec. Cert. Contact Lenses and Paedriatics) is an optometrist who practices in Optical In Sight (Doncaster East VIC) www.opticalinsight.com.au