It's not so good for your circulation to overplay your favorite series, a new review of the research shows. The study showed that people who regularly watched TV four or more hours a day were more likely to develop a blood clot that can lead to serious health problems and even death. What's more, this increased risk was seen independently of other important factors such as a person's physical activity level.
The condition is known as venous thromboembolism, or VTE, and is caused by blood clots that form in our veins. The most common form of VTE is deep vein thrombosis (DVT), which is when these blood clots get stuck in the deepest veins of our body, usually along our legs or pelvis, but sometimes in our arms.
DVT clots can cause acute swelling and pain when they occur, although many people may not experience any symptoms. These blockages can then damage the valves in our veins, especially if they are not treated early, leading to long-term complications such as chronic pain, swelling and sores. And the blood clots can also become detached from their original place and clog the arteries in our lungs, where they can cause a life-threatening condition called pulmonary embolism. It is estimated that close to one million people in the United States can develop DVT each year, and that up to 100,000 Americans die annually from the combination of DVT and pulmonary embolism.
Common risk factors for VTE include age, vein damage, and pre-existing health conditions such as heart disease. But it is also known that just being too long in one place can also increase the risk that is often seen when people are tied to a hospital bed due to serious illness. So it's not exactly a surprise that some researchers have wondered if long sessions in front of the TV could also be a potential contributor to VTE.
Lead author Setor Kunutsor of the University of Bristol and his team have already studied how to best prevent cardiovascular disease such as VTE. So they wanted to better understand the connection between TV viewing and VTE by reviewing and jointly analyzing the few studies that have specifically looked at the subject.
They analyzed data from three previous observational studies involving more than 130,000 participants 40 years of age and older who had not been diagnosed with VTE at the start of the study. Their health was tracked for over several years, sometimes for up to 20 years, and they were also asked about their lifestyle habits, including their TV viewing time.
In total, about 1,000 people were diagnosed with VTE at some point during the study period. Those who met the criteria to be long-term TV viewers - four or more hours a day on average - were 35% more likely to develop VTE than those who never or rarely watched TV. The team's results were published Wednesday in the European Journal of Preventive Cardiology.
The authors are careful to note that this type of research can only show a link between TV viewing and VTE, not proving that the former helps cause the latter. And because there have been only a few studies of this connection, the authors say, further research is needed to clarify how harmful prolonged television viewing can be to our veins. But the connection was found even when other factors that could increase or decrease the risk of VTE were taken into account, which further supported the idea that binge-watching in itself is a unique danger.
"The association was independent of age, gender, body mass index and physical activity, which is strongly related to the risk of VTE," Kunutsor told Gizmodo in an email. "This means that the relationship we observed between TV viewing and VTE risk cannot be explained by age, gender, body mass index, and physical activity. The relationship does not depend on these factors."
Long periods of sedentary behavior are obviously the strongest plausible explanation for why bingewatching may increase VTE risk. And it already is known that TV watching is associated with heart disease for the same reason. But there is also the possibility that people's diets while binge watching TV are likely to be unhealthier in general, leading to other conditions such as high blood pressure that further increase this risk.
While the relationship between television and the risk of blood clots may exist even for people who stay in shape, it does not mean that physical activity is worthless. Kunutsor and his team have previously found that exercise has a protective effect by preventing VTE, regardless of body mass index. And even if you'm committed to your marathon of addictive shows, you can probably still lower your risk of VTE by taking the time to stay active.
"If you want to focus on watching TV, take regular breaks in between. You can stand and stretch every 30 minutes," said Kunutsor, noting that the same advice applies to those who sit at work for long hours every day. .
If you are already physically active but still need to sit at work and / or love to binge, he added, "now is the time to increase your level of physical activity as there is evidence to show that higher amounts of moderate and vigorous activity can reduce or even eliminate the negative risks associated with sedentary behavior. "