Heavyweight campaigns failing children

The battle against childhood obesity is proving as difficult for governments as it often proves for people battling weight gain.

The evidence so far shows that many schemes to prevent childhood obesity have failed to make a significant dent in the girths of young Australians, a report by Productivity Commission researchers has found.

The report assesses 27 programs, whose titles rang from Romp and Chomp to Tooty Fruity Vegie Project and whose aims include increasing exercise, improving diet and cutting time sitting in front of screens.

While the programs may have had greater success encouraging healthier diets and exercise, ''some of the interventions are very expensive, making it unlikely that their limited benefits outweigh the costs,'' say the commission researchers, Jacqueline Crowle and Erin Turner.

Their 170-page report: Childhood Obesity: an Economic Perspective is published by the Productivity Commission but with the rider that the views in the report do not necessarily reflect those of the commission.

''On balance, governments appear yet to find a way to effectively intervene to reduce obesity prevalence among children,'' the report says.

This could reflect the inherent complexities and multiple causes of obesity and might also reflect deficient policy and evaluation.

The latest figures show that the rate of obesity among boys up to age 17 has risen dramatically in the past two decades to 10 per cent, with a further 16 per cent deemed overweight. The rise in prevalence of obesity among girls has levelled off to about 5 per cent, although a higher proportion than boys, about 18 per cent, are overweight.

The report says that while Australian children are exposed to a ''relatively high number of advertisements for energy-dense nutrient-poor foods'', evidence of cause and effect between food advertising and obesity ''is uncertain''.

A spokeswoman for the Obesity Policy Coalition, Jane Martin, said the conclusions were in contrast to the evidence-based recommendations of the government-appointed Preventative Health Taskforce.

The taskforce called for a comprehensive approach including policies to reduce junk food marketing to children and improved package labelling, Ms Martin said.