PROJECT SUMMARY/ABSTRACT Rates of obesity for Black adolescents are among the highest of any racial or ethnic group in the United States, and loss of control over eating (LOC; being unable to control what or how much one is eating) confers greater risk for the development and maintenance of excess weight. LOC occurs in 25-44% of Black youth with overweight and obesity, and Black youth eat more calories than their White counterparts during LOC episodes, compounding the risk of excess weight gain. Nevertheless, existing explanatory models of LOC do not capture the unique social contexts in which LOC occurs in Black youth, specifically the social nature of LOC in this population and the role of minority-specific social stressors, such as racial discrimination. Using a synthesis of qualitative data and ecological momentary assessment, this K23 proposal seeks to understand the social contexts in which LOC occurs in Black adolescents, and specifically to probe the association between racial discrimination and LOC. Focus groups (N = 4-5) will first be employed to gain a qualitative understanding of the contexts in which LOC occurs, the specific language that Black youth use to describe it, and how it may be linked to racial discrimination. Data from these groups will then be used to inform the EMA protocol in a second set of adolescents with concurrent OWOB and LOC (N = 30), which will assess the interplay between individual vulnerabilities for LOC and the larger social context, including racial discrimination. To carry out this K23, I will receive mentorship from a leading team of experts in the areas of obesity and eating disorders, health disparities, and ecological momentary assessment. This K23 will specifically facilitate my training in culturally sensitive assessment of both LOC and racial discrimination, engagement in community-involved research, and design and conduct of EMA research. This training will enable me to achieve my long-term goal of becoming a leading independent investigator focused on understanding the large-scale contextual factors that drive obesity related health disparities in racial and ethnic minority youth. Additionally, executing this K23 will also enable me to achieve two short-term goals: 1) submitting a subsequent R03 to create a culturally adaptive measure of LOC that can be used to identify this problematic behavior in both research and clinical settings and 2) integrating the findings from this K23 to create an intervention program targeting LOC and obesity in Black adolescents in a subsequent R01. Therefore, in addition to aligning with NIH’s UNITE initiative aimed at addressing structural racism and promoting health equity within biomedical research, this K23 proposal will serve as a launching point for my career as I leverage the training and research skills afforded by this award to become a leader in the field of adolescent obesity prevention and intervention for racial and ethnic minority youth.