If you’ve spent a weekend of binge watching House of Cards or Orange is the New Black on Netflix, you may want to get off the couch. According to a recent study presented at the European Society of Cardiology 2015 conference in London, watching television for more than five hours a day can make you twice as likely to suffer from a fatal pulmonary embolism.

In the U.S., the average American watches more than five hours of live television every day, according to a March 2014 “Cross-Platform Report” by the Nielsen media ratings company. Over 30 minutes a day is spent on time-shifted television. TV viewing is known to steadily increase to seven hours a day once you pass age 65. This is because you’re more likely to watch a lot of TV while you’re young and mostly at home and then drop your viewership when you hit your teens and begin to develop outside interests. Afterward, viewing rises in a straight line for the rest of your life, specifically increasing from about 23 hours during your early 20s to about 28 hours in your mid-20s to mid-30s.

So how does prolonged TV watching affect your health?

In the recent study funded by the Japanese government, Dr. Toru Shirakawa, public health research fellow in the Department of Social Medicine at Osaka University and his colleagues sought to observe the link between prolonged TV watching and fatal pulmonary embolism. This condition results in the blockage in the pulmonary artery, where the blood vessel varies blood from the heart to the lungs. Over 86,000 participants, both men and women aged 40 to 79 years were tracked for an average of 18 years until 2009. These participants previously completed a self-administered questionnaire, including information about average TV watching time per day as part of the JACC Study, which started between 1988 and 1990.

The duration of TV watching split into three groups, including less than 2.5 hours, 2.5 to 4.9 hours, and five or more hours per day. The risk of death from pulmonary embolism based on the length of TV watching was determined after the researchers adjusted for age at baseline, gender, history of hypertension, history of diabetes, smoking status, drinking status, body mass index, walking an sports habits, and menopausal status. Death from pulmonary embolism was identified from death certificates. There were a total of 59 deaths from pulmonary embolism.

“We have known about the relationship between prolonged sitting and pulmonary embolism for some time, but this is the first time a direct link between prolonged television watching and fatal pulmonary embolism has been shown,” Shirakawa said in a press release.

The findings revealed people who sit in front of the TV for five hours or more a day have twice the risk of suffering a deadly blood clot compared to those who watch less than two and a half hours per day. Within the 40 to 59 age group, those who watch more than five hours daily face more than six times the risk for pulmonary embolism than those who watch less than 2.5 hours a day. Those who watch anywhere from 2.5 to 4.9 hours daily are more than three times as likely to develop a fatal blood clot compared to those watching less.

"Leg immobility during television viewing may in part explain the finding," Troy said. "To prevent the occurrence of pulmonary embolism, we recommend the same preventive behavior used against economy class syndrome. That is, take a break, stand up, and walk around during the television viewing."

Pulmonary embolism does not just come from binge-watching TV, however. The same scenario can be found for those who sit in front of the computer for a prolonged time without taking a break. Blood clots are more commonly associated with long-distance flights due to sitting still in a confined space for long periods of time. Therefore, the longer you are immobile, the greater your risk of developing a blood clot.

Although the exact number of people affected by deep vein thrombosis and pulmonary embolism is not known, there are as many as 900,000 people affected in the U.S., says the Centers for Disease Control and Prevention. About 60,000 people die every year from pulmonary embolism within 30 to 60 minutes after the symptoms start. These symptoms include shortness of breath, chest pain, and dry coughing.

When it comes to pulmonary embolism, prevention is key. The bottom line: Limit TV and sit time, and increase fit time for an active lifestyle.

Sources: Shirakawa T. Prolonged television watchers have higher risk of fatal pulmonary embolism. European Society of Cardiology 2015 conference in London.