New research has revealed that children who have a TV in their bedroom are, on average, more likely to be overweight than their counterparts with no television access in their rooms.
The study was carried out by researchers from Dartmouth College in the US, and observed the habits of 3,000 10 to 14-year-olds over four years.
They found that children with a television in their bedroom gained weight at the rate of approximately one pound per year more than their peers without a TV in their room.
The link between the presence of a bedroom TV and faster weight gain held up even after researchers had controlled factors such as socio-economic status, education levels and parenting styles.
Most surprisingly, the correlation remained in evidence regardless of how much time the child spent actually watching the television - and even when the TV was not used at all. This may suggest that owning a personal TV might be a signal of a more sedentary lifestyle.
Researchers also warned that faster weight gain, particularly the 'belly fat' associated with sedentary TV viewing and the associated consumption of fatty, high-sodium snack food, meant a higher risk of developing diabetes and heart disease in later life.
Studies have shown owning a personal TV is increasingly the norm for young people, with one paper concluding that 71 had a computer with access to the internet.
However, although American paediatricians recommend limited 'screen time' for children - no more than two hours per day - a new study purports to show that giving children access to motion-sensing games consoles such as the Nintendo Wii and the Xbox Kinect increases their activity.
This study claims that, over a four-month period, overweight children who played these consoles lost twice as much weight as those enrolled on a weight management programme, suggesting that the link between screen-based entertainment and unhealthy lifestyles is far from clear-cut.