Physical inactivity increases your risk of suffering life threatening blood clots by up to 35 percent.
Doctor Setor Kunutsor from the University of Bristol found that watching TV for longer than four hours a day is a risk factor independent of other common health variables.
He said: “The findings indicate that regardless of physical activity, your BMI, how old you are and your gender, watching many hours of television is a risky activity with regards to developing blood clots.
“Our study findings also suggested that being physically active does not eliminate the increased risk of blood clots associated with prolonged TV watching.”
Doctor Kunutsor noted that as an observational study it does not prove that the act of watching TV causes blood clots.
Doctor Kunutsor speculated that the study’s association for TV watching may be more to do with how people do it than the television itself.
“Prolonged TV viewing involves immobilisation which is a risk factor.
“This is why people are encouraged to move around after surgery or during a long-haul flight.
“In addition, when you sit in a cramped position for long periods, blood pools in your extremities rather than circulating and this can cause blood clots.
“Finally, binge-watchers tend to eat unhealthy snacks which may lead to obesity and high blood pressure which both raise the likelihood of blood clots.”
Doctor Kunutsor concluded that the study is relevant not just to TV watchers but anyone who spends long periods inactive.
He said: “Generally speaking, if you sit a lot in your daily life – for example your work involves sitting for hours at a computer – be sure to get up and move around from time to time.”