Plenty of research has proven that watching too much television as a child causes serious health problems years later, and raises the risk of obesity, heart disease, diabetes, high cholesterol, poor fitness and smoking.

TV and computer games interfere with children's ability to sit behind a book and concentrate as the brain get used to the fast visual stimulation and loses its ability to concentrate or do the abstract thinking required by reading a book. Aggressive behaviour in children is also related to too much TV.

The health and behavior problems will be far greater for the next generation, as children now have access to far more TV and other electronic media than they did when the research began.

Some governments are considering banning advertising - particularly for fast food - during the hours children are more likely to be watching.

The Royal Australasian College of Physicians issued the results of research into the effects of electronic media on children. It said too much television could interfere with children's growth and development.

Today, children have access to scores of satellite channels, games, videos, DVD mobile phone games and the internet.

It's not just that children who were already overweight decided to watch more television. Rather, children who watched a lot of television were likely to become overweight.

If we really want to do anything about the obesity epidemic, we have to make some hard choices like reducing the amount of TV kids watch and their access to junk food.

Recent research shows that teenagers and young adults who watch more than just one hour of television a day are more likely to get into fights and exhibit other aggressive behavior in the years ahead than their peers who spend less time in front of the TV. It does not matter what the kids are watching. TV violence was so pervasive that simply watching a lot almost guaranteed extensive exposure. Most children spend an average of 4.5 to 5 hours a day engrossed in television, video games, computers and other media, all of which often have violent content. More aggressive children grow up to be more aggressive adults.

There is a lot of pressure for kids to watch TV from their friends at school, but I think society and parents really need to think about how we can reduce it. Of course TV can be a source of good entertainment, documentaries or educational programs such as the ones on Discovery Channel for example. However, more often than not, kids are left alone to watch hours and hours of mindless cartoons and video clips which glamorize sex and violence.

You are the role model. Switch off the TV and pick up a book instead. Forget the news. There is very little news "on the news". It is mostly tragedy, disasters, wars, crimes and politicians lying to get re-elected. It is pretty depressing and stressful. You learn very little and waste your precious time. We should all be watching less TV.