How many new health studies tell us all about how our sedentary behavior (code for time spent watching screens) is killing us? Every other day a new article says we are more prone to being diagnosed with this disease or that ailment because we spend too much of our precious time, both at home and on our jobs, simply sitting. Now, a new study from researchers in Spain finds adults who watch TV three hours or more a day may be doubling their risk of premature death.

“Heard it!” (You say). But what you haven’t already heard is this: Computer time and driving time were not significantly associated with higher rates of death. "Our findings are consistent with a range of previous studies where time spent watching television was linked to mortality," said Dr. Miguel Martinez-Gonzalez, the study's lead author and chair of the Department of Public Health at the University of Navarra.

A recent study of 6,329 Americans wearing activity monitors found they spent about 55 percent of their day pretty much sitting around: in particular watching TV, driving, and wandering around on the Internet. For the current study, then, a team of researchers accessed data from the SUN Project (Seguimiento Universidad de Navarra or University of Navarra follow-up) in order to determine if any relationship existed between three types of sedentary behaviors — TV viewing time, computer time, and driving time — and risk of death. The team followed a total of 13,284 participants, all college graduates, about 62 percent women, and an average age of 37 for roughly 8.2 years.

What did the researchers discover? During the study period, 97 total deaths were reported: 19 caused by cardiovascular events, 46 from cancer, and 32 from other causes. The data, once analyzed, indicated the risk of death from any of these causes was twice as high for those participants who reported watching three or more hours of TV each day compared to those who watched only one hour or less.

Remarkably, computer or driving time did not match up to a higher risk of premature death. (I guess no one studies those of us who half-watch TV while using the computer.)

Perhaps these results should not astonish. A recent study of Dutch adults also reported TV time, but not computer time, was linked to detrimental changes in biomarkers, while another study in an Asian population reported TV time, but not reading or computer time, was related to worse cardio-metabolic biomarkers. Could it be the fault of the shows themselves? Content is king.

Source: Basterra-Gortari FJ, Bes-Rastrollo M, Gea A, Nunez-Cordoba JM, Toledo E, Martınez-Gonzalez MA. Television Viewing, Computer Use, Time Driving and All-Cause Mortality: The SUN Cohort. Journal of the American Heart Association. 2014.