TV, computer, smartphone, tablet… With the digital revolution, screens have taken an important place in our professional and personal living spaces, whether with the youngest or the oldest. But the omnipresence of screens on a daily basis can be harmful to our health, with in particular theappearance of visual disturbances (myopia, loss of vision from afar, etc.) or a too pronounced sedentary lifestyle. On this subject, a study carried out by researchers at Bristol University issues a warning to big fans of television: it is better to take regular breaks when you watch it excessively to avoid blood clots.
Their study published in the European Journal of Preventive Cardiology explains that watch television for four hours a day or more is associated with a 35% higher risk of blood clots compared to watching television less than 2.5 hours a day. Specifically, the researchers looked at the association between television viewing and the risk venous thromboembolism. This includes deep vein thrombosis and pulmonary embolism. In the first case, it is an obstruction of a deep vein by a thrombus (clot). This thrombus can migrate into the pulmonary arteries causing a pulmonary embolism.
No more than 2.5 hours of television per day
To conduct the study, they proceeded to a systematic review to collect all available published evidence on the subject, and then combined the results 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 results of an individual study. explains the lead author of the study, Dr. Setor Kunutsor. The analysis included three studies with a total of 131,421 participants aged 40 years and older without venous thromboembolism pre-existing condition, whose time spent watching television each day was assessed by means of a questionnaire.
The answers were used to classify the participants into viewers watching television at least four hours a day or viewers watching television less than 2.5 hours a day. The average duration of follow-up in the three studies ranged from 5.1 to 19.8 years and during this period, 964 participants developed a venous thromboembolic disease. The researchers analyzed the relative risk of developing this pathology in so-called “extended” viewers compared to “occasional” viewers. They then found that the former were 1.35 times more likely to develop venous thromboembolic disease than the latter.
“Physical activity does not eliminate the increased risk of blood clots”
The association was independent of age, gender, body mass index (BMI) and physical activity. “The results indicate that regardless of physical activity, BMI, age and gender, watching television for many hours is a developmentally risky activity. blood clots. “says Dr. Setor Kunutsor. “The results also suggest that physical activity does not eliminate the increased risk of blood clots associated with prolonged television viewing. That’s why you need to take breaks: you can stand and stretch every 30 minutes or use a stationary bike. »
Regarding the hypothesis to explain this causal link, the researchers believe that prolonged viewing television involves being immobile, a risk factor for venous thromboembolic disease. Which is why people are encouraged to move around after surgery or on a long-haul flight. Moreover, in a prolonged sitting position, blood tends to pool in the extremities instead of circulating, which can cause blood clots. Finally, binge-watchers also tend to eat unhealthy snacks which can lead to obesity and hypertension, increasing the risk blood clots.
“We should limit the time we spend in front of the television. Long periods of television should be interspersed with movement to maintain blood circulation. Generally speaking, if you sit a lot in your daily life, for example if your job is to sit in front of a computer, make sure to get up and move sometimes. concludes Dr. Setor Kunutsor. It is therefore advisable to walk for a few minutes and to stretch after 2 hours in a row in a seated or lying position, knowing that “anti-sedentary” tips exist: put a reminder on his phone, get up to make a coffee or drink a glass of water…