Story highlights Sedentary behavior is the fourth-leading risk factor of death

Exercise helps, but exercise doesn't seem to balance out the bad impact of sitting

Little steps: Stand during TV commercials and get up for a minute or three every half hour at work

(CNN) One of your favorite activities may actually be killing you.

Our entire modern world is constructed to keep you sitting down. When we drive, we sit. When we work at an office, we sit. When we watch TV, well, you get the picture.

And yet, a new study that's running in the Annals of Internal Medicine found that this kind of sedentary behavior increases our chances of getting a disease or a condition that will kill us prematurely, even if we exercise.

JUST WATCHED 2012: Longevity versus inactivity Replay More Videos ... MUST WATCH 2012: Longevity versus inactivity 01:12

Researchers from Toronto came to this conclusion after analyzing 47 studies of sedentary behavior.

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