Scientists are warning that that watching TV for four hours a day or more is associated with a 35% higher risk of blood clots compared with less than 2.5 hours.
“Our study findings also suggested that being physically active does not eliminate the increased risk of blood clots associated with prolonged TV watching,” said lead author Dr. Setor Kunutsor of the University of Bristol, UK. “If people are going to binge on TV they need to take breaks. They can stand and stretch every 30 minutes or use a stationary bike, and they need to avoid combining television with unhealthy snacking.”
A meta-analysis included three studies with a total of 131,421 participants aged 40 years and older without pre-existing VTE. The amount of time spent watching TV was assessed by questionnaire and participants were categorised as prolonged viewers (watching TV at least four hours per day) and never/seldom viewers (watching TV less than 2.5 hours per day).
The average duration of follow-up in the three studies ranged from 5.1 to 19.8 years. During this period, 964 participants developed VTE. The researchers analysed the relative risk of developing VTE in prolonged versus never/seldom TV watchers. They found that prolonged viewers were 1.35 times more likely to develop VTE compared to never/seldom viewers. The association was independent of age, sex, body mass index (BMI) and physical activity.
Regarding the possible reasons for the observed relationship, Dr. Kunutsor commented: “Prolonged TV viewing involves immobilisation which is a risk factor for VTE. This is why people are encouraged to move around after surgery or during a long-haul flight. In addition, when you sit in a cramped position for long periods, blood pools in your extremities rather than circulating and this can cause blood clots. Finally, binge-watchers tend to eat unhealthy snacks which may lead to obesity and high blood pressure which both raise the likelihood of blood clots.”
Dr. Kunutsor concluded: “Our results suggest that we should limit the time we spend in front of the television. Long periods of TV watching should be interspersed with movement to keep the circulation going. Generally speaking, if you sit a lot in your daily life – for example your work involves sitting for hours at a computer – be sure to get up and move around from time to time.”
The research has been published in the European Journal of Preventive Cardiology, a journal of the ESC.1
1. Kunutsor SK, Dey RS, Laukkanen JA. Television viewing and venous thrombo-embolism: a systematic review and meta-analysis. Eur J Prev Cardiol. 2022. doi:10.1093/eurjpc/zwab220.
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