Even one hour of screen time a day significantly increases the risk of nearsightedness, especially for children, a new study suggests.
Even one hour of screen time a day significantly increases the risk of nearsightedness (myopia), especially for children, a new study suggests.
More Screen Time, More Risk
Researchers found that spending an additional hour per day (past the first) watching screens was associated with a 21 percent increase in the odds of someone developing nearsightedness.
The study analyzed data from 45 different studies involving over 335,000 participants to find a complex relationship between screen time and nearsightedness risk. The analysis collected data from various digital devices like smartphones, tablets, gaming consoles, computers, and televisions sets, which are collectively referred to as digital devices.
The findings of the systematic review and meta-analysis, recently published in JAMA Network Open, highlight a growing concern over children’s screen usage.
“As children increasingly embrace smart devices at younger ages and spend more time on digital screens, there is an urgent need to better understand the association of digital screen time with myopia,” the researchers wrote.
In the United States, estimates show nearsightedness prevalence to be about 42 percent. Among children specifically, as much as 41 percent of children in urban areas and 16 percent of children in rural areas are living with the condition.
The results suggest that daily screen time should be limited to under one hour to potentially reduce the risk of developing the condition where you can see objects near to you clearly, but objects farther away appear blurry.
Building on Previous Research
Previous meta-analysis combining data from 11 studies that included 934 participants looking at the relationship between screen time on smart devices (such as smartphones or tablets) and nearsightedness revealed a significant link—time spent on smart devices alone was associated with a 26 percent increase in the odds of developing nearsightedness.
When this screen time was combined with computer usage, the odds increased by 77 percent.
However, another meta-analysis that analyzed screen time data separately for different categories found that time spent on computers and televisions was linked to nearsightedness, but smartphone use was not.
The researchers involved in the new study note that findings like these highlight a need for more in-depth investigations into the safety threshold for digital device exposure.
