Mom was right: Too much TV CAN kill you

Looks like moms across America have been validated. All the warnings issued to their kids that "TV can rot your brain" just might be true -- sort of -- after all. At least, according to a new study it can.

Watching television has already been linked in studies to an increased risk of heart disease and obesity. But many of those studies included participants who were already overweight. Now, a new study examined TV's impact on longevity with participants who started the study at a healthy weight and had no prior history of heart disease. And the numbers aren't good.

The study, published in the current issue of Circulation, a journal of the American Heart Association, says each hour a day spent watching TV was linked with an 18% greater risk of dying from cardiovascular disease, an 11% greater risk of all causes of death, and a 9% increased risk of death from cancer.

TV watchers who spent more than four hours a day showed an 80% greater risk of death from cardiovascular disease and a 46% higher risk of all causes of death, compared with those who watched fewer than two hours a day, suggesting that being sedentary could lessen your longevity.

The researchers weren't surprised all that sitting doesn't help your muscles any. Doctors say muscle contractions are necessary for vital processes like breaking down glucose and using it for energy.