July 5, 2023
By Dwight Akerman, OD, MBA, FAAO, FBCLA, FIACLE
According to the International Myopia Institute Prevention of Myopia and Its Progression report, at a minimum, lifestyle advice and visual health guidance should be provided to all pre-myopic and myopic children. This advice encompasses outdoor exposure, close work time, and working distance.
Outdoor exposure during childhood is the most critical lifestyle risk factor known thus far. Outdoor exposure prevents or delays the onset of myopia and potentially slows progression. The protective effect of being outside is currently explained by a high light intensity leading to higher retinal dopamine, an ocular growth inhibitor. Also, pupils are more constricted outdoors, causing a greater depth of field, less image blur, and less peripheral hyperopic defocus, resulting in less myopic stimulus.
A practical piece of advice that combines several recommendations is the 20-20-2 rule: after 20 minutes of close work, children should gaze in the distance for at least 20 seconds and play outside for at least two hours a day. In addition, close work should be performed at a distance of at least 12 inches (30 cm).
In summary, eye care professionals should strongly advise all children and parents to:
- Apply the WHO guidelines for children under 5 years of age.
- Ensure that children over the age of 5 spend more time outdoors and less time on digital devices. Recommend outdoor sports and play of at least two hours per day in total, spread between outdoor school activity and after school.
- Take breaks every 20 minutes by looking across the room for 20 seconds when using a digital device or reading and spend a minimum of two hours per day outdoors (20-20-2 rule).
- Children should not spend more than three hours a day — in addition to school time — on close work such as reading, homework, or screen time.
- Reading and digital device usage should be performed at a distance of at least 12 inches (30 cm).
How can parents monitor their children’s time outdoors and working distance to ensure adherence to the recommended guidelines? At Apple’s Worldwide Developers Conference held June 5, 2023, (WWDC23), the company announced that it will incorporate new visual health features into its Health app with its iOS17 software update launch this fall, with a specific emphasis on myopia. The new software update will contain two critical myopia-related features: tracking outdoor time and measuring the distance that iPhone or iPad users are holding their devices from their faces.
With watchOS 10 (the software update to come this fall for Apple Watches), Apple Watch introduces the ability to measure time spent in daylight using the ambient light sensor. Users can view the time spent in daylight detected by their Apple Watch in the Health app in iOS 17 and iPadOS 17. Children who do not have their own iPhones (not many of these around) can use Family Setup to pair their Apple Watch to their parent’s iPhone, giving parents visibility into the amount of time their kids spend in daylight with Health Sharing.
Additionally, the new Screen Distance feature uses the same TrueDepth camera that powers Face ID on iPhone and iPad to encourage users to move their device farther away after holding it closer than 12 inches for an extended period. Screen Distance can remind younger users to engage in healthy viewing habits that lower their risk of myopia and allow adult users to reduce digital eyestrain.
The new features of iPhone iOS 17, iPadOS 17, and watchOS 10 that encourage healthy behaviors and help reduce the risk of childhood myopia are a welcome addition to addressing the global myopia pandemic. Especially important is Apple’s watchOS 10, which measures time spent in daylight using the ambient light sensor.
Congratulations to Apple for taking these proactive steps to protect the visual health of children and adults.
Best professional regards,
Dwight H. Akerman, OD, MBA, FAAO, FBCLA, FIACLE
Chief Medical Editor