According to research published in the December issue of the American Journal of Preventive Medicine, too much time spent watching television is associated with an increased risk of early death.
Previous studies have reported a relationship between TV viewing and death from heart disease and cancer. This study, carried out by the US National Cancer Institute, found that there is also a higher risk of death from diabetes, pneumonia, Parkinson’s and liver disease.
Over 221,000 healthy volunteers between the ages of 50 and 71 were included in the study. The researchers found that people who spend between three and four hours a day watching television are 15 per cent more likely to die from any cause. Those who watched for seven hours or more were 47 per cent more likely to die during the study period. For most causes of death, risk begins to increase at three to four hours a day.
Other factors were accounted for to confirm the association, such as alcohol and calorie intake, and the general health of the participants compared with the general population.
Sarah Keadle, the study’s lead investigator, said: ‘We know that television viewing is the most prevalent leisure-time sedentary behaviour and our working hypothesis is that it is an indicator of overall physical inactivity. In this context, our results fit within a growing body of research indicating that too much sitting can have many different adverse health effects.’
The researchers also observed that the detrimental effects of excessive TV watching are also found in active people. Dr Keadle said: ‘Although we found that exercise did not fully eliminate risks associated with prolonged television viewing, certainly for those who want to reduce their sedentary television viewing, exercise should be the first choice to replace that previously inactive time.’
The study’s authors say that more research is needed to fully understand the connection between TV viewing and mortality, and that the results should be compared with other sedentary activities such as driving or sitting at a desk.
In 2011 researchers from the University of Queensland in Australia reported that every hour spent watching TV shortens your life by 22 minutes.
In the UK the average person watches TV for three hours and 52 minutes every day.