Jan. 21, 2022 -- Here’s another reason to avoid a sedentary lifestyle.

People who sit and watch TV at least 4 hours daily had a 35% higher chance of getting potentially fatal blood clots than people who watch TV for 2½ hours or less daily, a new study says.

The study, published Thursday in the European Journal of Preventive Cardiology, looked at health information from three previously published studies of ​​131,421 adults aged 40 and older with no history of venous thromboembolism, or VTE. The participants self-reported the amount of TV they watched and were labeled as prolonged viewers (watching at least 4 hours daily) and never-seldom viewers (less than 2½ hours daily).

Over a period of 5 to 20 years, 964 participants got VTE. The condition includes pulmonary embolism, a blood clot in the lungs, as well as deep vein thrombosis, a blood clot in the legs that can cause pulmonary embolism.

Those who said they watched TV 4 or more hours per day were 1.35 times more likely to have VTE than those who watched TV an average of 2½ hours per day, the study said.

“If you are going to binge on TV, you need to take breaks. You can stand and stretch every 30 minutes or use a stationary bike. And avoid combining television with unhealthy snacking,” Setor Kunutsor, MD, of the University of Bristol in the United Kingdom, said in a news release.

While the study found a link between TV-watching and blood clots, that doesn’t prove TV-watching causes the blood clots, the researchers stressed. But the link occurred despite age, sex, body mass index (BMI), and physical activity.

“Our study findings also suggested that being physically active does not eliminate the increased risk of blood clots associated with prolonged TV watching,” Kunutsor said in the release.

He noted that people are also encouraged to move around on long airplane flights or after surgery.

“When you sit in a cramped position for long periods, blood pools in your extremities rather than circulating, and this can cause blood clots,” he said.

Researchers combined the findings of three studies and came up with a result using a process called meta-analysis.

“Combining multiple studies in a meta-analysis provides a larger sample and makes the results more precise and reliable than the findings of an individual study,” Kunutsor said.

Show Sources

European Journal of Preventive Cardiology: “Television viewing and venous thrombo-embolism: a systematic review and meta-analysis.”

European Society of Cardiology: “TV watching linked with potentially fatal blood clots.”

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