Watching too much TV may shorten lifespan

Spending your days in front of the television may contribute to a shortened lifespan, a new study suggests.

Researchers in Australia found that people who averaged six hours a day of TV lived, on average, nearly five years less than people who watched no TV.

For every hour of television watched after age 25, lifespan fell by 22 minutes, according to the research led by Dr. J. Lennert Veerman of the University of Queensland. But other experts cautioned that the study did not show that TV watching caused people to die sooner, only that there was an association between watching lots of TV and a shorter lifespan.

Though a direct link between the two is highly provocative, the harms of TV are almost certainly indirect, said Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine.

"As a rule, the more time we spend watching TV, the more time we spend eating mindlessly in front of the TV, and the less time we spend being physically active," Katz said. "More eating and less physical activity, in turn, mean greater risk for obesity and the chronic diseases it tends to anticipate, notably diabetes, heart disease and cancer."

Another explanation for the possible link may be that people who watch excessive amounts of TV "are lonely or isolated or depressed, and these conditions, in turn, may be the real causes of premature mortality," he added.

The report was published in the online edition of the British Journal of Sports Medicine.

The statistics suggest that too much TV may be as dangerous as smoking and lack of exercise in reducing life expectancy, the researchers said.