Australia's obesity problems are far from over as health experts were shocked to find new evidence that indicated 40 per cent or 4 out of 10 Australians are now dangerously fat or obese.

The Baker IDI Heart and Diabetes Institute tracked 11,000 Australians and monitored their waist circumference for 12 years. The results of the study surprised experts, according to Anna Peeters, President of the Australian and New Zealand Obesity Society.

She said a man should not have a waist more than 102 cm and a woman not more than 88 cm. Associate Professor Peeters will present the scientific findings of the obesity society in Melbourne on Oct. 17. She expressed her approval of the government's growing interest in fighting obesity but she still urged parents to intervene for the sake of their children.

Ms Peeters also spoke of the need for an early intervention to prevent obesity in children. She said Australia can learn from the U.S. with a declining rate of obesity.

Only a few schools in Australia strictly observe the dietary guidelines. Ms Peeters also recommends offices and other workplaces to rethink their food options including those inside their vending machines. Ms Peeters, who is also the head of obesity and population health at Baker IDI, defined obesity as a health condition of an inactive but wealthy society that "consumes in excess."

Obesity studies have found that Aussies with less income and education who are living in rural areas are most at risk to the dangerous effects of obesity because of cheaper and less nutritious food.

She was concerned about people who are a little overweight and thinking too much about weight loss. She said Australians should be more concerned on how to prevent weight gain. A person who is a little overweight at 30 years old will be more likely to be overweight at 50 years of age.

Associate Professor Tim Gill from the University of Sydney said parents should restrict the sugar intake of children to prevent them from growing up obese. Australians may be burning only a few calories a day that every calorie should only be from healthy and nutritious food.

Professor Gill said sweets should not entirely be banned from the child's diet but parents are advised to only allow two small sweet treats a day. He said sugary drinks should only be given once a week.