Abstract Eating disorders (ED) are serious psychiatric illnesses associated with various medical and functional complications. It is unknown which specific cognitive-affective mechanisms driving EDs impact the development of medical and functional complications, and whether targeting these mechanisms through personalized treatment leads to better outcomes than existing “one-size-fits-all” interventions. Furthermore, it is unclear how social determinants of health (SDOH) impact the heterogeneity of EDs and how they should best be integrated into treatment. The long-term research goal of the diversity supplement candidate, Mr. Juan Hernandez, is to created new innovative, efficacious, and cost-effective personalized ED treatments for diverse communities. Consistent with this goal, the current Diversity Supplement proposes to use idiographic network modeling to examine individual differences in ED symptom presentations and test whether a personalized intervention approach outperforms existing front-line treatments (i.e., CBT-E). The current proposal builds on the parent grant (DP2MH136495) and will uniquely contribute to the literature by examining how individual differences in EDs are associated with medical and functional complications and SDOH, each of which directly impact longevity and quality of life. Grounded in existing literature, we hypothesize that central cognitive- affective mechanisms will vary across individuals and will be more associated with medical disorders and functional outcomes (i.e., health-related quality of life, physical functionality and vitality, health perceptions, achievement of self-defined goals) than behavioral symptoms. We also hypothesize that more disadvantaged SDOH (e.g., more severe food insecurity, more experiences of marginalization) will also be associated with more medical disorders and worse functional outcomes. As per treatment effects, we hypothesize that at post- treatment, the personalized treatment condition will be associated with less medical disorders and better functional outcomes compared to the front-line treatment condition. Lastly, we hypothesize that at post- treatment, the personalized treatment condition will not be as impacted by SDOH as front-line treatments across medical and functional outcomes. This study will be the first to examine (a) individual differences in EDs impact on medical and functional complications and (b) how to best incorporate SDOH into ED treatment to address medical and functional complications. Results will inform important etiological and treatment questions that will directly inform efforts to promote longevity and quality of life among those experiencing an ED. The conceptual, quantitative, and professional rigor of the training plan will prepare Mr. Hernandez to meet his long-term goal of conducting clinical ED research at a Research 1 University. With the post-doctoral training from this supplement, Mr. Hernandez will increase diversity of the field and fill ...