��One in 10 people in Australia aged 15 and older have an eating disorder, but fewer than 20% seek appropriate treatment. This is among several grave insights revealed by an extensive and long-running work by 91����’s Eating Disorders and Body Image (EDBI) group.

“Reducing delays in seeking treatment, and barriers to care, are my biggest challenges,” says Professor Phillipa Hay, EDBI leader.

To better pinpoint who needs treatment and help them access it, Hay and her team of clinicians and researchers are unmasking the many and varied types of eating disorders in Australia, and evaluating what therapeutic techniques work.

The field first piqued Hay’s interest when, as a trainee psychiatrist in New Zealand, a mentor encouraged her to explore research into eating disorders.

At the time, the mental health field recognised one eating disorder: anorexia nervosa, which was defined by restrictive eating and an intense fear of gaining weight, despite being severely underweight. Its formal description can be traced back to the 1870s, but Hay realised that, more than a century later, anorexia treatment techniques were still not based on evidence.

Anorexia nervosa has one of the highest fatality rates of any non-substance-abuse psychiatric disorder, even greater than major depressive disorder, but early treatment regimes were crudely designed. “Looking back on it now, they were quite punitive, restrictive behavioural programmes,” Hay says.

“People were admitted to hospital and only given privileges if they gained weight, with very little psychological understanding of what they were experiencing.”

Hay later completed a PhD on the features of emerging eating disorders, bulimia nervosa and binge eating disorder, and in 1995, set in motion one of the world’s few large-scale longitudinal projects in the field.

In the study, which is part of the annual South Australia Health Omnibus Survey and continues today, thousands of people aged 15 years and older are questioned about, among other health aspects, eating behaviours and treatment for disorders. Their responses often contradict the eating disorder stereotype of the thin, white, affluent teenage girl.

The latest survey snapshots, published in 2017, showed that a binge eating disorder, characterised by uncontrolled rapid consuming of large quantities of food, was the most common major eating disorder, affecting one in 70 respondents.

In comparison, bulimia nervosa, anorexia nervosa (broadly defined) and avoidant/restrictive food intake disorder were each reported by one in 100, 200 and 300 people, respectively.

People with an eating disorder who did not meet full threshold criteria to be classified under the major types of eating disorders were much more prevalent. These ‘unspecified’ and ‘other specified’ eating disorders made up around 10% and 3% of the surveyed population, respectively.

Hay’s survey also showed that eating disorder rates have, over time, become more evenly distributed across sociodemographic sectors. For instance, even though eating disorders develop most often in young women, they’re rising on a faster trajectory in women over 45 years old and men.

But the group with both high body mass index (BMI), and disordered eating, is increasing faster than either factor alone, Hay says.

Hay says that incidences of eating disorders in Aboriginal and Torres Strait Islander people are as high, or higher than in the general population, but they don’t fit the generally accepted profile.

Behaviours behind this high eating disorder prevalence in 91���� Australians are not clear cut, according to Dr Deb Mitchison, an EDBI research fellow, who found a similar incidence in a survey of adolescents.

“First Australians in general usually have a higher BMI, so you might think the behaviours are all about binge eating. But it’s other types of disordered eating too, like extreme dieting and purging.”

In addition to revealing the true extent of eating disorders, Hay’s group develops and evaluates treatment techniques and strategies. Their work informs clinical practice guidelines locally and abroad.

“Her clinical leadership has been enormous in Australia and internationally,” says Professor Susan Paxton, a psychologist from La Trobe University.

Hay and Paxton have collaborated on evaluations of eating disorder treatments and interventions and have shown that not all people with an eating disorder necessarily need specialist intervention.

For instance, findings from a randomised clinical trial showed guided self-help, provided by a GP to people with bulimia nervosa, an eating disorder defined by cycles of binge eating followed by compensatory behaviours such as vomiting, had similar outcomes to psychological therapies delivered by specialists.

Other treatment trials show cognitive behavioural therapy, delivered by a psychologist or psychiatrist, is most effective for recovery from long-term anorexia nervosa.

“Vital to knowing what works in treatment interventions for eating disorders, is speaking with people with an eating disorder about their lived experiences,” EDBI researcher and clinical psychologist Dr Janet Conti says.

“Aspects of Phillipa’s research are dedicated to understanding eating disorders from the perspective of the person with a lived experience, and using these insights to inform treatment.”

Clinicians now know that treating the person with respect, and keeping their normal life as intact as possible rather than a “doctor knows best” paternalism, is crucial to long-term recovery. Current treatment approaches for people with an eating disorder focus on providing a personalised out-patient treatment plan, so patients don’t lose connections with people, school or work – an approach used at Wesley Hospital Ashfield, where Hay is director of the Wesley Eating Disorders Centre and involved in a day programme. “People come in, get peer therapy, and group therapy, and dietetic support while continuing with their lives,” Hay says.

“Change might be slower than an intensive inpatient programme, but it’s far more likely to be sustained in a person, who can also maintain other important parts of their life.”

Identifying those with an eating disorder, and facilitating recovery is of critical importance, but with so few people accessing treatments, how can interventions reach those who need them?

This is the question that plagues Hay. Behaviours such as binge eating and strict dieting in the general population have increased over time, and one in five people with an eating disorder are, according to the BMI metric, considered overweight or obese.

A significant barrier to overweight people receiving eating disorder treatment is the skinny stereotype, which endures not only in patients’ minds but also, frequently, in the perception of doctors. “Often when a person presents to a GP, the GP doesn’t see someone who’s not very thin as having an eating disorder,” Hay says.

“The person might also think ‘I can’t have bulimia nervosa because I have a high BMI’.”

GPs asking the right questions, too, seem to influence the likelihood of people accessing treatment. In 2019, Hay, Conti and colleagues found people with an eating disorder were likely to seek specialist mental health intervention when a GP asked about their mental health, but not if the GP enquired about their diet or eating habits.

Like all mental health conditions, early intervention in eating disorders is important. Left too long, treatment becomes more difficult, but it’s never too late to seek help. Hay says: “I’ve seen people recover from eating disorders who have had the illness for 20 or 30 years. There is always hope.”