When it comes to weight issues and health, it is the rise in obesity that has the focus of many of Australia's health experts. The figures are concerning.

Obesity rates have doubled in the past 20 years and the rates of adult onset diabetes are growing as a result.

But there is another weight-related health problem that has received less attention, and that is eating disorders. It is estimated eating disorders affect as many as one in 10 Australian women.

The latest research shows that levels of concern about body image are showing up in younger children.

Child psychiatrist Dr Sloane Madden suggests that half of all 10 and 11-year-old girls are unhappy with their body.

"Being overweight is seen as being lazy, even by younger children," he said.

Eating disorders are the third most common chronic illness in young people, preceded by obesity and asthma.

"We estimate that one in 200 women have anorexia while as many as 20 per cent have disordered eating," Dr Madden said.

"One-quarter of the cases are in children under 12."

The average duration of an eating disorder is six years, and less than half of the women diagnosed with an eating disorder will get better.

But the outcomes in children are better. Dr Madden says 70 per cent of children who receive family therapy will recover, and the earlier treatment is started the better.

The illness is showing up in more young boys who aspire to have more muscles rather than be thin.

Experts say many patients with eating disorders suffer other mental health problems. As many as 80 per cent suffer from depression and 75 per cent have signs of anxiety.

Patients suffer a range of physical complications, such as cognition, osteoporosis, infertility and growth delay in children.

Brains shrink

Dr Madden says the brains of patients with anorexia shrink.

"Patients who are starved have impaired attention, they think more slowly and their thinking becomes more concrete and rigid," he said.

He says there are some early warning signs parents can look for.

Cutting food into small pieces or cutting out food they enjoy, avoiding sharing meal times and making excuses for missing meals, are all potential warning signs.

Also having an increased interest in food preparation can also be a sign of an eating disorder.

Dr Madden says by the time most children and teenagers with eating disorders get treatment, 60 per cent have life-threatening physical complications from their illness.

He says there is a lack of specialist services to treat children and young people, particularly in rural and regional areas.

The National Eating Disorders Collaboration is a Federal Government initiative aimed at developing a national approach to eating disorders.

This week, the NEDC's media advisory group held its first meeting.

It aims to develop media industry guidelines for reporting and depicting eating disorders, disordered eating and negative body image in the media.