Teens who spend a lot of time watching TV are more likely to be overweight, the Boston Herald reported.

That might sound familiar, but the authors of a study from the Boston Children’s Hospital say they’ve delved deeper into the issue, in order to find out which types of screen time are worse.

“It may seem obvious that if you’re sitting at home, watching a lot of TV, you’re not getting a lot of exercise, but it’s much more complicated than that,” said Boston Children’s Hospital scientist David Bickham.

Researchers studied 91 teenagers, between the ages of 13 and 15, tracking their use of television, computers, video games and mobile screens for two weeks. The more intently children watched TV, researchers found, the higher BMI they were likely to have, the Boston Herald said.

However, there was no link between video game and computer use and higher BMI levels, researchers said.

“All screen time is not the same,” said Dr. Michael Rich of Children’s Hospital’s Center for Media and Child Health.  “With video games and the computer, your hands are busy, there’s less advertising … TV sets up an environment where food consumption is easy.”

“Television is financially supported by advertising, and that advertising is almost never for broccoli,” Rich added. “Most of the ads are for what’s called high-calorie, nutritionally questionable foods.”

Bickham added, “If you’re engaged with the TV, you’re not paying attention to the food you’re eating or the cues that your body is giving.”

Researchers ultimately hope parents can use this data to help kids get off the couch.

“Instead of saying, ‘Pitch your television out the window,’ we’re saying, ‘Use media mindfully, and understand the risks,’ ” Rich said.

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