Background: 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.

Methods: 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.

Results: 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).

Conclusions: 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.