AbstractObjectivePeople with Type 1 diabetes (T1D) face an increased risk of eating disorders/disordered eating (ED/DE), with adolescents being particularly vulnerable. Empirical knowledge on the mechanisms underlying development of ED/DE in T1D is crucial for evolving prevention strategies.Research Design and MethodsFourteen semi‐structured interviews with adolescent females with T1D and ED/DE between 14 and 18 years were conducted and analyzed using reflexive thematic analysis.ResultsAnalyses identified four main themes; ‘Interconnected afflictions’, ‘Judgment’, ‘Feeling Different’, and ‘Chaos & Control’, These themes explore the interconnectedness of T1D and ED/DE, with shame and guilt emerging as common underlying mechanism. The development of a biopsychosocial model was based on the integration of these data with existing models.ConclusionsThe study extends previous developmental pathways of ED/DE in adolescents with T1D. We propose a biopsychosocial model that incorporates various factors: predisposing factors such as parental management of T1D and weight gain during adolescence; precipitating factors including comments on weight, frequency of weighing, perceptions of surveillance; the perpetuating bilateral influence of ED/DE and T1D and finally highlighting the protective mechanisms of disease acceptance encompassing parental handling of diagnosis and the contribution of healthcare professionals (HCP's) role in psychoeducation. The present study highlight the vulnerability of adolescence in the presence of T1D, particularly concerning issues related to eating, weight, and body. It offers clinically relevant insights, with the aim to improve communication and management strategies for this very specific group.