Hours of inactivity slumped in front of a television sharply raises the risk of dying from a blood clot in the lungs, say scientists.
A Japanese team studied the TV viewing habits of more than 86,000 people aged 40 to 79 between 1988 and 1990.
They found that every additional two hours viewing per day increased the risk of fatal pulmonary embolism by 40 per cent.
Participants who watched five or more hours of programmes daily were more than twice as likely to die over the following 19 years than those who watched less than two and a half hours.