Spending time outdoors is beneficial to health in general, and research increasingly indicates that it may also provide some protective measures against myopia progression in young children. A study that followed children from birth to age nine in Singapore recently added to this evidence, finding that prolonged time outdoors can decrease the odds of myopia.
The study included 483 children (966 eyes; 50% boys, 59.8% Chinese, 42.2% myopic) who spent a reported average of 100 minutes per day outside, based on questionnaire responses, a smart watch device and a seven-day activity diary. They were exposed to average light levels of 458±228 lux.
The researchers found that for those who spent time outside in light levels of 1,000 lux or more (37 minutes per day), 76% of the time was spent below 5,000 lux. The children had 1.7 light exposure episodes per day.
“Common outdoor activities were walks, neighborhood play and swimming,” the researchers reported. “Greater reported time outdoors was associated with [significantly] lower odds of myopia.” Light levels, timing and frequency of light exposure, on the other hand, weren’t associated with myopia, cycloplegic spherical equivalent or axial length.
The researchers concluded that time outdoors was protective against myopia development and progression and advised a “multipronged approach” to boost time spent outdoors among children to combat the myopia epidemic.
Li M, Lanca C, Tan C, et al. Association of time outdoors and patterns of light exposure with myopia in children. Br J Ophthalmol. April 15, 2021. [Epub ahead of print].