A study conducted at the University of Navarra in Pamplona, Spain suggests people who watch at least three hours of TV a day are two times more likely to die than people who watch less than one hour daily.

A research team from the university observed 13,284 Spanish university graduates with an average age of 37 years, and studied how much time each student spent watching TV, according to CNET. Results were adjusted based on age, sex, total energy intake, smoking status, body mass index, Mediterranean diet adherence and physical activity.

"Television viewing was directly associated with all-cause mortality. However, computer use and time spent driving were not significantly associated with higher mortality," the study reported. 

The participants were followed for a little over eight years and spent an average of two hours each day on the computer and close to an hour driving each day, NBC News reported.

"Participants reporting three or more hours a day of television viewing had a twofold higher risk of mortality than those reporting less than one hour a day," the University of Navarra's Dr. Martinez-Gonzalez and colleagues wrote.

Only 97 of the volunteers died over the eight years, while 128 of them were expected to die, which showed that the participants appeared to be healthier than the average person in Spain. 19 of those who passed away did so from stroke or heart disease, while 46 died from cancer and 32 died from other causes.

For each addiitional two hours the participants spent watching TV over one hour a day, there was a 44 percent greater chance of dying from heart disease or stroke, 21 percent greater chance of dying from cancer and 55 percent greater chance of dying from other causes, NBC News reported.

Other research shows that the average American raises his or her risk of colon cancer by 8 percent, of endometrial cancer by 10 percent and lung cancer by 6 percent for every two hours spent sitting in front of a television or computer.

The study was published in the Journal of the American Heart Association.

Despite all the data found in the study, the research team believes they must conduct follow-up studies for further understanding of the health effects of watching a certain amount of TV, CNET reported.

"Further cohort studies and trials designed to assess whether reductions in television viewing are able to reduce mortality are warranted," the team concludes in the paper. "The lack of association between computer use or time spent driving and mortality needs further confirmation."