Disordered eating behaviors (DEB) impact on health and wellbeing worldwide. This study aimed to examine sociodemographic trends in the prevalence of DEB over 20 years in the Australian general population.

Data were derived from five sequential cross-sectional surveys (1998, 2008, 2009, 2016 and 2017) with population-representative samples of adults and adolescents residing in South Australia (N = 15 075). DEBs investigated were objective binge eating (OBE), strict dieting/fasting, and purging. Sociodemographic data included gender, age, educational level, work and marital status, and residence.

OBE prevalence increased significantly. Strict dieting/fasting also increased from 1998 to 2008/9 but remained stable between 2008/9 and 2016/7. Purging prevalence did not change significantly over time. All survey years were associated with a significantly higher odds of OBE, and strict diet/fasting compared to 1998. Lower age, a higher Accessibility Remoteness Index of Australia (ARIA) score, higher body mass index (BMI), higher educational attainment, and not being in a married or de facto relationship were independently associated with greater adjusted odds for endorsing OBE. Younger age, female gender, and higher BMI were also independently associated with greater adjusted odds for endorsing strict dieting/fasting.

The increased prevalence of DEBs in various strata of Australian society has both public health and clinical implications. The results refute the stereotype that eating disorders (EDs) predominantly affect young women. They build impetus for future research on EDs among men and older individuals, with a view to developing tailored public health and clinical interventions for these populations.

We sought to provide the first point prevalence estimates of muscle dysmorphia (MD), a form of body dysmorphic disorder characterized by a preoccupation with perceived insufficient muscularity, in adolescents.

Data were taken from a survey of 3618 Australian adolescents (11.172–19.76 years; 49.3% girls). Measures captured demographic characteristics, symptoms of MD and eating disorders, psychological distress and functional impairment. Diagnostic criteria for MD developed by Pope et al. (1997, Psychosomatics, 38(6), 548–557) were applied, entailing preoccupation with insufficient muscularity causing significant levels of distress or disability that cannot be better accounted for by an eating disorder.

The point prevalence of MD was 2.2% [95% confidence interval (CI) 1.6–3.0%] among boys and 1.4% (95% CI 0.9–2.0%) among girls. Prevalence was not associated with gender (V = 0.031) or socioeconomic status (SES) (partial η2< 0.001), but was marginally associated with older age (partial η2 = 0.001). Boys with MD were more likely than girls with MD to report severe preoccupation with muscularity (V = 0.259) and a weight-lifting regime that interfered with their life (V = 0.286), whereas girls with MD were more likely to report discomfort with body exposure (V = 0.380).

While future epidemiological research using diagnostic interviews is needed to verify these estimates, the findings suggest that MD is relatively common from early to late adolescence. Gender differences in MD prevalence may be minimal; however, the symptom profile appears to diverge between boys and girls. These findings provide a platform for future, analytical research designed to inform clinical and public health interventions.

Little information is available on the prevalence of Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 eating disorders in adolescence, and eating disorders remain unique in the DSM for not systematically including a criterion for clinical significance. This study aimed to provide the first prevalence report of the full suite of DSM-5 eating disorders in adolescence, and to examine the impact of applying a criterion for clinical significance.

In total, 5191 (participation rate: 70%) Australian adolescents completed a survey measuring 1-month prevalence of eating disorder symptoms for all criterial, ‘other specified’ and unspecified eating disorders, as well as health-related quality of life and psychological distress.

The point prevalence of any eating disorder was 22.2% (12.8% in boys, 32.9% in girls), and ‘other specified’ disorders (11.2%) were more common than full criterial disorders (6.2%). Probable bulimia nervosa and binge eating disorder, but not anorexia nervosa (AN), were more likely to be experienced by older adolescents. Most disorders were associated with an increased odds for being at a higher weight. The prevalence of eating disorders was reduced by 40% (to 13.6%) when a criterion for clinical significance was applied.

Eating disorders, particularly ‘other specified’ syndromes, are common in adolescence, and are experienced across age, weight, socioeconomic and migrant status. The merit of adding a criterion for clinical significance to the eating disorders, similar to other DSM-5 disorders, warrants consideration. At the least, screening tools should measure distress and impairment associated with eating disorder symptoms in order to capture adolescents in greatest need for intervention.