Watching too much TV may double blood clot risk: study

Watching television for too long may double the chances of developing blood clots, a study has warned.

Prolonged TV viewing has already been associated with heart disease, but this is the first study to look at blood clots in veins of the legs, arms, pelvis and lungs known as venous thromboembolism (VTE).

"Watching TV itself is not likely bad, but we tend to snack and sit still for prolonged periods while watching," said Mary Cushman, from the University of Vermont in the US.

The researchers examined 15,158 middle-aged (45-64 years) participants.

The risk of developing a VTE was 1.7 times higher in those who reported they watch TV "very often" compared with those who watch TV "never or seldom".

People who met recommended guidelines for physical activity and reported watching TV "very often" had 1.8 times higher risk compared to those who reported watching TV "never or seldom".

"Think about how you can make the best use of your time to live a fuller and healthier life," said Cushman.

"You could put a treadmill or stationary bike in front of your TV and move while watching. Or you can delay watching TV by 30 minutes while you take a walk," she said.

Each year, it is estimated that between 300,000 to 600,000 people in the US develop VTE, making it the most common vascular diagnosis after a heart attack or stroke.

Although VTE is more common in people 60 and older, it can occur at any age.

"Besides avoiding prolonged TV watching, you can lower your risk of VTE by maintaining a healthy weight and staying physically active," Cushman added.