Associations between muscle dysmorphia symptoms and sexual functioning among sexually active boys and young men

Muscle dysmorphia is characterized by a pathological pursuit of muscularity, pronounced body dissatisfaction, and functional impairment. Although muscle dysmorphia symptoms have been linked with numerous adverse health and psychosocial correlates, its association with sexual functioning among boys and young men remains underexplored. This study examined associations between muscle dysmorphia symptoms and sexual dysfunction among sexually active boys and men (N = 1116). Data were drawn from The Study of Boys and Men, an online survey of males aged 15-35 years recruited via social media advertisements in 2024. Muscle dysmorphia symptoms were assessed using the Muscle Dysmorphic Disorder Inventory (MDDI), and eight domains of sexual functioning (e.g., anxiety, lack of arousal, physical pain, erectile dysfunction) were assessed using items from the National Survey of Sexual Attitudes and Lifestyles Sexual Functioning measure. Multiple logistic and linear regression models tested associations between MDDI scores (Drive for Size, Appearance Intolerance, Functional Impairment, and total score) and eight forms of sexual dysfunction, as well as an aggregate count of sexual dysfunction, adjusting for sociodemographic covariates. Greater muscle dysmorphia symptoms, particularly Appearance Intolerance and the MDDI total score, were consistently associated with a broad range of sexual dysfunction and a greater number of sexual dysfunctions. Drive for Size and Functional Impairment showed fewer, smaller, significant associations. These findings suggest that sexual dysfunction may co-occur with muscle dysmorphia among sexually active boys and young men, underscoring the importance of assessing and addressing sexual health within clinical and preventive interventions targeting boys' and men's body image.