Are Australian children active and eating well?

The most comprehensive survey ever taken of Australian children's diet and activity habits has revealed a picture of a generation where some children are eating a variety of healthy foods and are generally lean and active, while others are filling up on the wrong types of food and spending too long in front of the television.

To determine the links between diet, activity and excess weight gain, the 2007 Australian Children's Nutrition and Physical Activity survey - led by a team of CSIRO Preventative Health Flagship researchers and University of South Australia (UniSA) researchers - monitored children's body weight, activity levels and the type and volume of foods they eat.

UniSA Professor Tim Olds says about one quarter of the children surveyed were overweight or obese.

'This number hasn't increased over the last decade or so, and that's encouraging but it's still far too high,' Professor Olds says. 'Australian children spend very large amounts of time (3-4 hours a day on average) in front of a screen of some sort - TV, computer or videogame console. Swapping sedentary behaviours like TV watching for activities that get kids moving is a great step towards getting that number down.'

Project coordinator, Dr Jane Bowen of CSIRO's Preventative Health National Research Flagship, says since the previous surveys there have been some big changes in the Australian way of life.

'Many children are not eating enough nutritious food, which means they don't get the vitamins and minerals needed during their growth years,' she says. 'Unfortunately fruit, vegetables and dairy foods are being replaced by foods high in kilojoules, salt and saturated fat - the very dietary patterns linked to the development of type 2 diabetes, high blood pressure and heart disease in adults.'

The head of the Department of Nutrition and Dietetics at Flinders University Professor Lynne Cobiac, says the results for teenage girls are particularly worrying.

'As a group, teenage girls appeared to be getting insufficient amounts of calcium from foods. Eighty percent of 14 to 16 year old girls did not consume the recommended amounts of calcium. Girls this age also reported doing the least amount of physical activity. These two factors combined put them at risk of developing weak bones as they grow older.'

Dr Bowen says the survey involved more than 4,400 interviews with children aged 2 to 16 years and their parents.

'This information is essential because it provides the evidence governments and other organisations need to develop programs which promote good nutrition and healthy lifestyles in Australia,' she says.