For many adolescents, “screen time” is almost a full-time job that could lead to obesity, diabetes and other health issues, a Canadian researcher says. Adolescents now spend an average of six hours a day in front of some type of screen, whether it's a television or computer screen or one of the many portable devices now popular with young people, studies done by Dr. Ian Michael Janssen show. “They spend more hours daily in front of a screen than they do in a classroom in a given year,” said Janssen, a researcher at Queen's University in Kingston, Canada, who is funded by the Canadian Institutes of Health Research. Even if they are still playing with friends, children are increasingly likely to be engaging in more passive activities like playing video games, one reason why only half of Canadian children aged 5 to 17 get as much physical activity as they should each day, according to the Health and Stroke Foundation. The result is a rise in obesity rates among adolescents. Twenty-six percent of Canadian children are overweight or obese, according to a government health committee report, representing a 15-percent increase over 30 years. In the United States, the obesity rates for preschool-aged children and adolescents has more than doubled over that time period, and more than tripled for children aged 6-11. Unfortunately, fixing the problem isn't as easy as simply cutting down screen time, Janssen cautions. While a sedentary lifestyle has been associated with childhood obesity, as reported in the Canadian Medical Association journal, Janssen says that physical activity and screen time are separate behaviors in children. “Decreasing screen time will not automatically increase physical activity levels,” said Janssen, whose research examines how the two are related and what effects screen time may have above and beyond those on physical activity. Some active kids also spend a lot of time in front of television and computer screens, and some kids who have low screen times also have low levels of physical activity, he points out. What's needed is an approach that tackles both behaviors. Children who have high screen time and low physical activity are the worse off, Janssen said, in terms of negative health effects. A multifaceted approach that addresses both factors is necessary to fight childhood obesity, he said, because it is a societal problem with many facets. In science, it's called an ecological approach: it starts at the top level with global policy changes and works its way down into cities and communities, effecting change for individuals and families. Tackling just one piece of the problem can help, he said, but the effect will be subtle unless other factors change too. As well, screen time is not inherently bad, Janssen said. “The tricky part is that children today need to be using computers,” he said. Computers are required for schoolwork, and technological skills are important for future job prospects. The quality of screen time matters too, along with the quantity -- consider the negative health messages found in food advertising during children's shows, he said. Ideally, children should aim for no more than two hours of recreational screen time a day. Even a small change can have a large positive effect, Janssen said. It's recommended that children get at least 90 minutes of physical activity a day, he said, but any increase will pay off in health benefits. “As little as 30 minutes a day, although not ideal, can really do wonderful things for a child.” The long-term risk for children is that behaviors and health outcomes tend to track over time, Janssen said. “An obese youth is very likely to become an obese adult.” And because obesity-related health problems take time to develop, the longer a person has been obese, the worse off they're likely to be. A 50-year-old who only recently became obese is in a better position than one who has been obese since childhood, he said. Janssen's real worry about the rise in childhood obesity rates is not that there are now rare cases of type 2 diabetes in kids, where once there were none, but the health problems these children are likely to face in the future as adults, including high blood pressure, high cholesterol and cardiovascular disease. When today's obese children are adults, baby boomers will all be seniors, he pointed out, placing a huge burden on the health care system. “That's when I'm really frightened.”- Reuters __
