Our Children’s Health linked with Screen Time

On average children in the UK spend 6 1/2  hours a day in front of  a screen.  How does screen time affect our children’s health?

On average children in the UK spend 6 1/2  hours a day in front of  a screen. Teenage boys spend the most time, on average 8 hours a day (compared with 3 1/2 hours in 1995). Younger children fare slightly better: in 1995, 5 to 10 year olds averaged around 2 1/2 hours of TV. Fast forward to 2014 and their screen time has risen to 4 1/2 hours.  The type of screen has changed too over this period: in 1995 TV was the main source, but this has now been overtaken by the internet viewed via mobiles, tablets and computers and games consoles. 

By the age of seven the average child will have spent a full year of 24-hour days watching recreational screen media. Over the course of childhood, children spend more time watching TV than they spend in school.

So does this matter?   Well yes

Too much screen time can make it hard for children to sleep at night, increase their risk of attention problems, anxiety and depression and put them at significant risk of obesity. 

Screen time can lead to obesity for a number of reasons; sitting and watching a screen is time not spent being physically active. TV commercials can lead to unhealthy food choices. Mostly, the foods in adverts that are aimed at children are high in sugar, salt or fats. And children eat more when they are watching TV especially if they see ads for food.

In 2015 Cambridge University researchers recorded the activities of more than 800 14-year-olds and analysed their GCSE results at 16. Those spending an extra hour a day on screens (TV, computer, games console, phone) saw a fall in GCSE results equivalent to two grades overall: on average, the 14-year-olds said they spent four hours of their leisure time each day watching TV or in front of a computer. An additional hour of screen-time each day was associated with 9.3 fewer GCSE points at 16,  the equivalent of dropping a grade in two subjects. Two extra hours of screen-time was associated with 18 fewer points, or dropping a grade in four subjects. Even if pupils spent more time studying, more time spent watching TV or online, still harmed their results, the analysis suggested.

Researchers also suggest that screen viewing early in life is likely to lead to long periods of viewing later on. The way screens are viewed when young forms habits that can persist in the long term. An early taste for entertainment screen media can lead to changes in the brain. Like other addictions, screen time creates significant changes in certain chemicals in the brain: dopamine is produced when we see something that is interesting or new. It is also the chemical involved in most addictions – it's the reward chemical.There are concerns among some scientists that producing dopamine every single day for many years, through for example playing computer games, may change the reward circuitry in a child's brain and make them more dependent on screen media. Additionally, although children who are heavy users of electronics may become adept at multitasking, they loose the ability to focus on what is most important, a trait critical to the deep thought and problem solving needed in life.

Experts advise that teenagers should have a “screen-free” hour before bedtime, after new evidence suggested too much exposure to TVs, smartphones, tablets and computers can affect their sleeping patterns: in a study of 10,000 16 to 19-year-olds, researchers in Norway found that the longer a young person spent looking at an electronic screen before going to bed, the worse quality sleep they were likely to have. They also found that excessive screen time (more than 4 hours a day) was linked to anxiety and depression and was responsible for limiting a child’s opportunity for social interaction and physical activity, both of which are key factors in reducing childhood distress.

So how much screen time should we allow?

The simple answer is not much. None for children under two. The experts suggest that babies and toddlers are kept away from all screens. Children aged 2-5 years should have no more than an hour a day and children aged 5-18 years should have no more than two hours a day. That's a tough call for teenagers, especially with homework often requiring computer time. But the real danger is non-educational, leisure screen time, so homework screen time could be discounted.

Parents should be able to decide if these strictures are too harsh, and allow some flexibility, but not caring at all about the amount of time your children spend in front of screens may be dangerous.

Dr Harriet Doyle