I always figured shows like "Jersey Shore" killed more brain cells than marijuana... but it turns out that death risk extends to the rest of your body too.

A new study finds that those of us who spend the most time tuned in are most likely to check out early: Two or more hours of TV a day can increase the risk of diabetes, heart disease, and an early death.

Researchers from the Harvard School of Public Health looked at data from eight studies that tracked more than 200,000 people combined for 7 to 10 years.

And what they found should be enough to make anyone reach for the "off" button: Every two hours of daily screen time increases the risk of type 2 diabetes by 20 percent, heart disease by 15 percent, and death itself by 13 percent.

That's during the study period, of course -- we're all guaranteed death at some point. The trick is putting it off as long as you can... even if that means resisting the temptation to see how Ashton Kutcher does on "Two and a Half Men."

This isn't the first time TV has been linked to serious health problems. One recent study found that people who watch four or more hours a day face an 80 percent boost in the odds of heart disease and 46 percent increase in the risk of an early death. (Read more here.)

And plenty of other studies have found that kids who are glued to the tube risk obesity, developmental problems, social issues, and trouble with schoolwork.

One study I told you about earlier this spring even found that kids between the ages of 6 and 7 who watch the most TV already show some of the earliest warning signs of heart disease.

Of course, the real problem exposed by all these studies isn't Ashton Kutcher, the dregs of "Jersey Shore" or even the TV itself.

The problem is what we do while we watch: Nothing, often with bag of chips or box of cookies within close reach.

If you really want to save yourself, ditch the TV and the snacks and take up a hobby that involves regular movement

And if you really feel the urge to check in on "Jersey Shore," at least limit your viewing to a few hours a week instead of a few hours a day.