Can Too Much Screen Time Sabotage a Child’s Vision?
"We are noticing trends in how screen time impacts vision in children and we are trying to figure out the 'why,'" says Mary Ian McAteer, MD, a pediatrician at Indiana University Health. "Researchers tend to think this is related to the overuse of screens and excessive near work."
“Near work” is defined as time spent on a computer, smartphone, tablet or reading. There is evidence that both genetics and overstressing the eyes with near work can lead to myopia, or nearsightedness, in children.
"Through repeated practice, near work stimulates only certain parts of the visual system and the eye's lens doesn't get to 'work out' very much," Dr. McAteer explains. "The eye will adapt to experience and without experience focusing on distant objects, children may lose their ability to clearly see objects that are farther away. The eyeball itself will change its shape over time, becoming longer, which makes it hard to focus on faraway objects."
So, how much screen time is too much? To promote healthy vision in children, Dr. McAteer suggests:
- Limit a child's near work whenever possible, particularly related to entertainment since homework is inevitable. Dr. McAteer suggests parents use the following guidelines set forth by the American Academy of Pediatrics:
- No more than one to two hours of entertainment media per day for children over the age of two and teenagers
- No entertainment media or television for children under the age of two
- Have their child take 20-second breaks every 20 minutes when reading, writing, using a computer, or playing on a smartphone or tablet. "Our eyes need time throughout the day to focus on different things, not just near work," says Dr. McAteer.
- Encourage kids to spend more time outside. "Spending time outdoors stimulates a lot of brain function in children that involves vision," she says. Outdoor playtime also allows kids to focus their eyes on objects that are farther way and it exposes them to natural light, which helps them see more easily. As a bonus, they will get more exercise.
- Increase natural light exposure. Children typically use electronic devices in low indoor light, which requires their eyes to work harder to focus. When a child reads or uses an electronic device, parents should encourage him or her to do so near a large window with natural light or with a bright lamp nearby.