Watching hours upon hours of television may not turn you into a vegetable, but it sure will take years off your life, or at least that's what a new study published in an American Heart Association medical journal shows. Research indicates that the more time we spend in front of the TV, the greater risk we run of developing heart disease and dying earlier.

Nearly 9,000 adults with no history of heart disease were studied for a period of over six months - compared to those who watched less than two hours of TV a day, those who sat in front of the old telly for more than four hours a day were 80% more likely to die from heart disease and 46% more likely to die from 'any cause.'

Each additional hour spent in front of the TV increased risk of death by heart disease by 18% and overall risk of death by 11%. Here's a shocking (or perhaps, not so shocking?) part: 284 people died during the study.

The study took into account the education levels and overall health of all participants - so age, whether they smoked, their cholesterol and blood pressure, none of it was a factor in the results. So why is TV so deadly?

"Prolonged watching of television equals a lot of sitting, which invariably means there's an absence of muscle movement," Dunstan says. If your muscles stay inactive for too long, it can disrupt your metabolism, he explains.

Even extra exercise can't make up for hours spent in front of the boob tube, according to this study. When they compared groups of adults who exercised the same amount but watched varying amounts of TV, those who watched more TV were still at a higher risk of dying during the study.

An abundance of TV-watching means less time spent doing "non-sweaty" activities like standing, walking room to room, cooking and doing things with your hands - all of which are heart-healthy activities, yet are often overlooked and underestimated.

How does this information correlate to internet usage? Or studying, which is also conducted while in a sedentary position?

"Reading or doing homework doesn't seem to be associated with risk factors as much as television viewing," says Katzmarzyk, who was not involved in the study but has studied the health effects of sitting time. "We're not sure if it's the sedentary behavior itself or the other things you're doing during television viewing, like snacking."

Dunstan also attributes a lack of movement in the workplace to technological advancements in communication. While there are still many jobs that require you to be on your feet, moving, more and more people are spending their lives glued to a computer screen, instant messaging or e-mailing instead of walking down the hall to chat with a co-worker or client.

"Modern technology has virtually engineered a lot of incidental, non-sweaty activity out of our lives," Dunstan says.

What is Dunstan's overall advice for counteracting a shorter life spent sitting? "Just get up and move about during the day. The more you move, the greater the health benefits are likely to be."

What do you think - would you watch less TV if it meant you could live longer?

via CNN