By Dr Harry
“Screen time” is the term used to describe time spent in front of your TV, computer games, iPad, Nintendo DS, etc.
Recent research suggests that the more time we spend in front of a screen, the higher the risk of adverse health outcomes.
The average American child spends 7.5 hours per day in front of a screen (Canadians slightly more and for British children the figure is 6 hours per day). This is mostly discretionary screen time – in other words not related to school work. For adults the figure is higher, with more time spent in front of a screen than spent sleeping. In one study, more than 2 in 3 of us actively engage more than one screen simultaneously – such as watching TV and using a laptop.
Screen time is apparently much worse for your health than other sedentary behavior like reading a book or drawing/painting.
One reason is that average blood pressure readings on individuals watching TV or playing computer games is higher than those engaging in other sedentary behavior which does not involve a screen. This is thought to be due to the TV and video game content, which is more stressful or exciting and hence raises blood pressure.
Another reason is altered sleep patterns. Children who engage in more than 2 hours of screen time per day are less likely to sleep well and more likely to have sleep disorders and daytime tiredness, with the problems associated with this such as lack of attention and poor school performance.
Screen time is also very distracting. You have probably read in earlier blogs that eating while watching TV is not advised because you end up eating more because you are failing to notice signals from your body which let you know you are full. This effect also has an impact on memory, which makes you more likely to eat again a few hours later, simply because you have “forgotten” just how much food you ate at the last meal.
This effect on attention is obvious when you come home from work to greet your spouse and children only to find your greetings totally ignored because these family members are “engrossed” in screen time.
You would not find it surprising therefore to learn that the increase in screen time is having negative effects on our social interaction. Far from “social networking” being social, as the name implies, it is having the opposite effect with real world relationships suffering. This lead to low self-esteem and negative psychological outcomes, such as depression, anxiety and stress disorders as we zone out of reality and rely more and more on a network of virtual “friends”.
Obesity is on the increase due to many factors – one of which is less time spent on moderate to vigorous physical activity. The trend of increased screen time has a major effect on obesity promotion for the obvious reason that if you are spending a lot of hours in front of a screen, this is time which you are not able to use effectively at the gym, or outside the house exercising. Another fact is that your metabolic rate is slower during TV watching than during sleep. So when you think you are relaxing in front of the TV after a hard days work, perhaps you could just go to sleep instead – you could be burning more calories!