Governments are starting to take notice as a growing body of evidence suggests that television can harm very young viewers.
It's the telly monster
The Australian government recently announced that it would issue guidelines advising parents of children under two that their offspring should watch no television at all. This is a bold step in a country where young children spend more time watching TV than engaging in any other activity - the average four-month-old Australian is glued to the box for 44 minutes every day. And they are not alone. In the US, under-twos watch a daily average of 1.2 hours, while in Britain older children spend around five hours and 18 minutes watching television, playing computer games or online each day.
This media saturation is one of the reasons the Australian government felt compelled to act, following the example of France, where the authorities last year banned French channels from broadcasting shows aimed at children under three. And overseas cable channels screening children's TV must now incorporate a tobacco-style warning: "Watching television can slow the development of children under three, even when it involves channels aimed specifically at them," it reads ominously.
Since 1999 the American Academy of Pediatrics has advised parents of under-twos that their infants should watch no TV at all. So what compelled medical experts in three widely separated countries to issue such stringent guidelines? Jo Salmon, associate professor of epidemiology at the School of Exercise and Nutrition Sciences at Deakin University, Melbourne, was one of the researchers whose work informed the Australian government's guidelines.
She cites numerous studies that show a causal link between the time young children spend watching television and a wide range of problems, from less-developed vocabulary to poor attention spans and even aggressive behaviour. "For example, a 2001 study of 182 young children over a three-year period found that the four-year-olds who watched more TV performed significantly worse in letter, number and vocabulary skills," says Salmon.
Another study in 2007 followed more than 2,700 children from 30-33 months up to 5½ years. It found that the children who watched more than two hours of TV a day when they were younger were more likely to have sleep problems, attention problems, poor social skills and aggressive behaviour at age five. "If a child is less than two there is no evidence that TV is beneficial," says Salmon. "In fact, it could be harmful to children's health and development in the long run. I really would not put my young one under two in front of a television."
This view is backed up by thousands of high-quality, long-term studies that show screen media like video games, computers and, especially, television, can have a seriously detrimental effect on children of all ages. And for those under two, whose brains are both sensitive and growing at an astonishing rate, excessive exposure to screen media has been linked with a host of problems, from high blood pressure and obesity to ADHD, lower literacy rates and poor educational performance.
The remarkable thing is that, in the vast majority of developed countries, governments and health authorities have issued no guidance about this whatever. In fact, the British government recently introduced an Early Years Foundation Stage for zero to fives, which implies that television should be part of children's learning. And millions of caring, intelligent, well-informed parents happily plonk their tots in front of the "electronic babysitter" with no clue about the increasing concerns of doctors, researchers, child development experts and psychologists about the potential damage this may cause.
At the forefront of these experts is the clinical psychologist Aric Sigman, author of Remotely Controlled: How Television Is Damaging Our Lives. "In the US, parents are advised that children under two should not see any screen entertainment at all, because it may affect their brain development," he confirms. "It's nothing to do with the quality of programming, it's the very act of staring at the screen that causes damage."
Sigman explains that the brains of children under three are like pieces of clay being moulded in response to the stimuli they experience from the sights, sounds and other sensory data they receive from the outside world. When these delicate brains are assailed by garish, rapid-fire screen images, they may be profoundly affected. He also argues that we must differentiate between the programmes we watched as children and those broadcast now.
"Two things have changed," he says. "The editing speeds have gone up tremendously: up to 10 times faster than programmes we used to watch. There are also many more zooms, the colours are far brighter and harsher and the sound is much louder in so-called 'children's TV'. Second, when we were kids, TVs were incredibly expensive. Because they are now so cheap, when we buy a new set the old one often goes into our kids' rooms."
Sigman argues that this spells disaster, comparing it to installing a fridge in the bedroom of an obese child. He cites a recent study that found British children have up to three screens in their bedrooms and may watch two simultaneously, or flick back and forth between them. That's a far cry from the domestic scene of old, where the family gathered around a black-and-white set with a tiny screen to watch the odd programme together.
Too many parents have ceded control over their children's daily media diet, he says. And the result? "Attention damage is the main problem," says Sigman. "That's not just ADHD [attention deficit hyperactivity disorder]. We're talking about their ability to focus on a task, their performance at school and literacy level. Studies have shown that increasing time spent in front of screen technology is strongly linked to a decline in time spent reading books - preschool kids spend three times longer in front of a TV or computer than they do reading."
This compulsive relationship with screens of all kinds also has an impact on children's physical health. A study published this year in the Archives of Pediatrics and Adolescent Medicine found that children who spent the least amount of time in front of a screen had significantly lower blood pressure than those who spent the most. The study looked at 111 children aged between three and eight. On average, they spent 1.5 hours in front of screen media, although some were glued to their screens for considerably longer.
The researchers, from Iowa State University, believed that the main reason for the raised blood pressure - one of the risk factors in developing life-threatening conditions such as coronary heart disease and stroke - was that too much screen time kept children away from more active pursuits and sport. Dr Victor Strasburger, professor of paediatrics at the University of New Mexico School of Medicine, is a strong advocate of rationing the screen diet of children and adolescents. One of his main concerns is the link between excessive screen time and obesity.
"Numerous longitudinal studies - several conducted over a period of 25-30 years - shows that media use is contributing to the current epidemic of obesity worldwide," he says. "But we don't know why. It's probably a combination of things, including food advertising - in the US, young children see over 7,000 food ads a year, mostly for junk or fast food. Eating habits also change when you watch TV, so kids eat higher-fat, higher-calorie meals and snacks than they do when eating at the dining table with their family."
What about the most obvious reason - that spending all day slumped in front of the TV means youngsters are not out running around? "Everyone thought that was the key element, and there are some studies which lean that way," says Strasburger. "But others suggest that sedentary kids and teenagers would be so whether watching TV, reading a book or talking on the phone, so the evidence is inconclusive."
What is conclusive is the American Academy of Pediatrics' recommendation that young children should watch no TV at all. Strasburger explains why he and his colleagues made this decision - a decade before the French and Australians - and why parents should implement it with a dash of common sense. "Since 1999, we have recommended that parents avoid screen time for babies under two. That doesn't mean if you need to take a shower and want to park your kid in front of Sesame Street for 20 minutes it will do them irreparable harm, because clearly it won't. But it does mean they should avoid it."
Strasburger's reasoning echoes that of his European and Australian peers. "What we know about early brain development is that the infant brain is plastic and grows in response to environmental cues," he says. "So, quite literally, the nerves grow based on the environmental stimuli the baby is exposed to. If they are exposed to a real, live person, who can interact with them and interpret their cues accurately, that's great. If they're exposed to a person who looks real but is on a TV screen, it's not so good."
Sigman takes this argument one step further. "Kids under three should never, or very rarely, watch TV - and then only in the living room with their family. This is because a growing body of evidence strongly suggests that exposing young children to electronic media may pose problems for their development - especially their ability to pay sustained attention." Sigman also argues that older children, although less susceptible to damage, are still at risk. "There have been two studies recently looking at kids from five to 11 and 14 to 22. And the attention damage holds true - the amount of TV they watch is still linked with poorer school performance and educational outcomes."
As if this weren't reason enough to restrict your children's viewing, consider this: nearly 3,000 studies and reviews have found a significant relationship between media violence and real-world aggression; hundreds of studies show that tobacco advertising gives preteens and teenagers favourable opinions about smoking; and there is continuing research into the connection between television-watching and eating disorders, suicide and depression.
None of the experts quoted here is calling for an outright ban on TV or other screen media. What they are saying is that there is a direct link between screen time and a host of physical and psychological problems, especially for the very young. As Sigman puts it: "I'm not in favour of outlawing TV for kids. What should happen is that all governments and health authorities should inform us that there is growing concern about its effect on children - then it should be up us to decide what we want to do."