Prof Sawyer's comments come as a report released by the Butterfly Foundation estimated almost a million Australians suffered from eating disorders, costing the economy billions of dollars.
The Paying the Price report, compiled by Deloitte Access Economics, estimated there were currently 913,986 Australians with an eating disorder.
The report suggested 1829 people died from eating disorders in 2012, a far higher figure than the 14 the ABS estimated to have died in 2010.
Prof Sawyer said the report highlighted the difficulties sufferers and their families faced in accessing specialist treatment services.
It also demonstrated the lack of reliable data available in Australia on eating disorders.
"This report will help bring visibility to the burden of eating disorders on sufferers, their families and the community which due to personal shame and community stigma, continue to be a highly invisible group of conditions," she said.
The report found binge eating disorder (BED) was the most common type of eating disorder for both men and women. Almost half of those with BED are estimated to be obese.
An unspecified eating disorder was the second most common, followed by bulimia and anorexia.
The disorders were estimated to cost the nation's health system $100 million annually and account for $15.1 billion in lost productivity.
- AAP
For help or support for an eating disorder or body image issue call Butterfly 1800 334 673 or email support@thebutterflyfoundation.org.au.