Too much screen time for kids can lead to poor health, the American Heart Association (AHA) says. A scientific statement published by the AHA in the medical journal Circulation said screen time from smart phones, tablet computers and other devices can lead kids to a sedentary(惯于久坐不动的) lifestyle, increasing the possibility that they grow up as overweight or obese(肥胖的).
The AHA is the latestorganization urging parents to limit how much time their kids spend in front of screens. It recommends children get one to two hours of screen time each day. Although television viewing among children and teens has dropped, the use of smartphones and tablet computers has surged.
"Although the mechanisms(机制) linking screen time to obesity are not entirely clear, there are real concerns that screens influence eating behaviors, mainly because children don't notice when they are full when eating in front of a screen," said Tracie Barnett, a researcher at the INRS-Institute Armand-Frappier Research Centre, in a statement.
Barnett, one of the authors of the statement, also urges parents to keep screens out of kids' bedrooms, raising the fear that too much screen time can affect sleep.
Many studies have warned about the potential(潜在的) negative effects of too much screen time. Last year, a study from researchers at San Diego State University (SDSU) found nearly half of teens who spent five or more hours in front of screens every day experienced long periods of hopelessness or sadness.
Apple, who makes the iOS mobile platform, plans to introduce new tools to devices to help users cut back on screen time. As for iOS 12, iPhones will include a screen time feature where users can control and review how they spend time on their mobile devices. Another company that makes the Android(安卓)platform will introduce "digital well-being" tools such as screen time limits and a "wind down" option to encourage users to put down their phones before bed.
