Key Takeaways Spending more time outdoors is associated with a significantly lower risk of myopia in children and adolescents, with an overall risk reduction of about 25% A daily target of around 2 hours outdoors appears to offer meaningful protection while remaining practical for most families and school schedules Increasing outdoor activity may be a simple, low-cost strategy to help address the rising global prevalence of childhood myopia A large new international study has found that spending more time outdoors significantly reduces the risk of myopia among children and adolescents—offering new evidence for a simple, low-cost intervention in the face of a growing global vision crisis.1 Researchers analyzed data from more than 380,000 young people across China and found a clear relationship between time spent outdoors and reduced likelihood of developing myopia. The findings were published in the Journal of Global Health. Myopia has surged dramatically in recent decades, particularly in East Asia. In China alone, the proportion of school-aged children with poor vision increased sharply between the mid-1990s and 2010s, driven by intense academic demands, increased screen use, and reduced time outdoors, the researchers stated. Globally, researchers warn that nearly half of the world’s population could be myopic by 2050, raising concerns about long-term eye health and associated complications. The new research is a systematic review and meta-analysis of 31 studies conducted up to October 2025. Using a random-effects model, the researchers evaluated how different levels of daily outdoor activity correlate with myopia risk. The results show a consistent protective effect: Children who spent more time outdoors had a 25% lower overall risk of myopia (pooled odds ratio: 0.75). Even modest increases in outdoor time made a difference: 1–2 hours/day → reduced risk 2–3 hours/day → reduced risk Over 3 hours/day → greatest reduction Notably, children spending more than two hours outdoors daily had significantly lower odds of developing myopia compared to those with less than 1 hour. While more outdoor time generally led to better outcomes, researchers highlighted around 2 hours per day as a realistic and effective target within current school systems. Although the study focused on statistical relationships, prior research suggests several biological mechanisms behind the protective effect. Exposure to natural light may help regulate eye growth and reduce the elongation of the eyeball—a key factor in myopia development. The findings also reinforce concerns about modern lifestyles, where children spend increasing time indoors engaged in near-work activities such as studying or using digital devices. The study’s authors say their findings could inform education policy and public health strategies. Schools may consider increasing outdoor recess or physical education time, while parents are encouraged to promote outdoor play. Reference 1. He X, et al. Association between outdoor time and risk of myopia in children and adolescents: a systematic review and meta-analysis. J Glob Health. 2026;16:04122. doi:10.7189/jogh.16.04122