Couch potatoes take note. Sitting in front of the TV for hours on end could shave years off your life.
Researchers estimate that for every hour an adult spends watching TV their life expectancy shortens by almost 22 minutes.
Those glued to the box for six hours a day slice nearly five years off their lives compared to those who don’t watch TV.
While sedentary behaviour has previously been linked to an increased risk of dying from cardiovascular disease, this study is the first to look how TV habits affect how long you live.
Researchers from the University of Queensland said their study indicated that watching TV could have a similar impact on life expectancy to that of obesity, smoking and low physical activity.
“People don’t realise how it all adds up,” the study’s lead author Dr Lennert Veerman told AAP.
“They should try not to watch too much TV and find alternative things to do, preferably things that are light activities.
“They should watch the news and keep themselves informed, but if in the rest of their lives they are pretty active, I wouldn’t tell them not to watch a movie.”
The study was based on data from the Australian Diabetes, Obesity and Lifestyle study, which began in 1999 and asked more than 11,000 people aged over 25 about their weekly TV viewing.
The researchers then compared the viewing times with Australian mortality rates.
They found that in 2008 Australian adults watched 9.8 billion hours of TV and for every hour spent in front of the box their life expectancy dropped by 22 minutes.
Those who watched the most TV a day – six hours – lived 4.8 years less than those who watched none.
“These findings suggest that substantial loss of life may be associated with prolonged TV viewing time among Australian adults,” the researchers wrote in their study, published on Tuesday by the British Journal of Sports Medicine.
“TV viewing time may have adverse health consequences that rival those of lack of physical activity, obesity and smoking; every single hour of TV viewed may shorten life by as much as 22 minutes.
“With further corroborative evidence, a public health case could be made that adults also need to limit the time spent watching TV.”
The federal government recommends Australians spend at least 30 minutes a day doing moderate-intensity physical activity.
Those who are fairly inactive face an increased risk of developing conditions including cardiovascular disease.
The Heart Foundation’s national clinical issues director Dr Robert Grenfell said people who sit for long periods of time should regularly get up and move about.
“Because TV viewing is a ubiquitous behaviour that occupies significant portions of adults leisure time, its effects are significant for overall population health,” he said.