Increase in Myopia Among Children: Sunlight Offers Potential Solution
Outdoor time plays a crucial role in reducing the risk of childhood myopia, or nearsightedness, according to numerous studies. Spending at least 1 to 2 hours daily outside can significantly lower the chances of developing myopia compared to those who spend less time outdoors [1][3][4][5].
This protective effect is primarily attributed to natural light exposure, which increases dopamine release in the retina, regulating eye growth and preventing excessive elongation of the eyeball – the anatomical cause of myopia [2][4]. Being outdoors also typically involves viewing objects at varying distances, reducing the eye strain associated with prolonged near work or screen time, both linked to myopia progression [3][5].
Moreover, the ambient light outdoors is much brighter (especially late morning to mid-afternoon), which seems to have a protective effect against myopia development [1].
Recommendations for real-world implementation suggest encouraging outdoor play, outdoor breaks during screen activities, and scheduling activities such as bike rides or walks to ensure children get sufficient daylight exposure. Combining outdoor time with other interventions, such as low-dose atropine if needed, offers the best protection for vision health [1].
It's essential to note that while outdoor time is beneficial, it won't guarantee long-term eye health. Increasing the amount of time spent outdoors and following strategies like the 20-20-20 rule (looking at something 20 feet away for at least 20 seconds for every 20 minutes of screen-based or up-close activity) can help reduce myopia risk, but any amount of myopia that can be prevented can help reduce the chances of complications and possible vision loss later in life [6].
The National Academies of Sciences, Engineering and Medicine's recent consensus study report also encourages increased outdoor time during daylight for young children and persistent outdoor activity throughout childhood and into young adulthood [7]. The World Health Organization suggests that children under two have no screen time at all and for children ages two to five to limit their screen use to no more than one hour per day [8].
In addition to its role in preventing myopia, sunlight supports vitamin D production, which strengthens ocular tissues, reduces eye inflammation, improves corneal function, aids in tear secretion, and strengthens the sclera [9]. Vitamin D is also thought to play a role in preventing or improving conditions such as age-related macular degeneration, diabetic retinopathy, dry eye disease, and uveitis due to its anti-inflammatory and anti-oxidative properties [9].
In conclusion, consistent daily outdoor time of 60 to 120 minutes in natural light is a scientifically supported, simple, and effective measure to reduce the risk of childhood myopia [1][3][4][5]. Encouraging outdoor activities and limiting screen time are crucial steps in promoting children's eye health and overall well-being.
- Nature, as a source of natural light, plays a vital role in regulating eye growth and reducing the risk of childhood myopia, according to numerous studies [2][4].
- Promoting health-and-wellness through outdoor activities can significantly lower the chances of developing medical-conditions like myopia, especially when combined with strategies like the 20-20-20 rule and appropriate screening for conditions such as age-related macular degeneration or diabetic retinopathy [1][6][9].
- Science shows that fitness-and-exercise, mental-health, and nutrition all benefit from spending time outside, in addition to providing protection against eye-health issues like myopia [1][6][7][9].
- Encouraging a lifestyle that emphasizes health, wellness, and outdoor time is crucial for children's overall development, as it supports the prevention of various medical-conditions, including myopia, and improves vision health, while contributing to a broad range of physical and mental health benefits [1][6][7][9].
