Melbourne: Spending your days in front of the television may contribute to a shortened lifespan, a latest Australian study has said.
The findings were made today by an Australian team led by Lennert Veerman of School of Population Health at University of Queensland.
"If our estimates are correct, then TV viewing is in the same league as smoking and obesity," Veerman said.
"We`ve taken that study and translated it into what it means for life expectancy in Australia given how much TV we view," Veerman said.
His team estimated that every single hour of TV watched after age 25 was associated with a reduction in life expectancy of around 22 minutes.
"Given that Australians watch on average around two hours of TV a day, that would reduce life expectancy at birth by 1.8 years for men and about 1.5 years for women," he said.
Veerman said the small proportion of people who watch six hours of television a day would reduce their lifespan by 4.8 years.
Veerman said that according to conservative estimates, every cigarette took 11 minutes off a smoker`s life expectancy and compared the risk to that run by television viewers.
"At the individual level there are few things worse you can do than smoking," he said.
But he said that while smoking rates were on the decline, almost everybody watched TV, and TV viewing should be seen as posing a serious threat to public health at a population level.
Veerman said that while the figures from his study were statistically significant, there was a large degree of uncertainty about them because the 11,000 people involved in the study still constituted a small sample.
But he said other studies, for example from England and Scotland, had also found TV viewing reduced lifespan.
He said a recent analysis of all such studies in the Journal of the American Medical Association suggested the risk from TV viewing was lower than their findings than in the University of Queensland study.
"If you apply these pooled results, then for every single hour of TV that you watch after age 25 you could on average expect to lose five minutes of your lifetime.
"He said the differences in estimates may be attributable to different age groups being studied, and a different interpretation of TV viewing.
His study only classified someone as watching TV if they were doing nothing else - such as cooking or some other activity - at the time.
Last year, another Australian study, by David Dunstan and colleagues from the Baker IDI Heart and Diabetes Institute in Melbourne, found an hour of TV viewing a day led to an 8 per cent increase in the risk of premature death.