PROJECT ABSTRACT The overall goal of this K01 award is to provide Gina Tripicchio, PhD, MSEd, with the training and mentorship to establish an independent program of research focused on innovative behavioral interventions to improve dietary intake in high-risk adolescents. Added sugar (AS) is a prime target for dietary intervention in adolescents; it contributes excess calories with no nutritional benefits, and adolescents consume more AS than any other age group. High-risk adolescents (e.g., racial/ethnic minorities from low-income communities), experience disproportionately higher rates of obesity and diet-related chronic diseases yet remain understudied. A key limitation in developing efficacious trials for this high-risk group is the dearth of information about key factors associated with AS intake. To address this gap, this project aims to characterize key drivers of AS intake in high-risk adolescents using ecological momentary assessment (EMA). EMA allows for the examination of contextually specific dietary influences in real-time, while reducing recall bias and participant burden. This rich information can be used to guide the development of a tailored, salient behavioral intervention. Additionally, an objective carbon stable isotope ratio (CIR) biomarker of AS has recently emerged and can be used to address key limitations of self-reported outcomes in dietary interventions. Two studies will be employed to meet the aims of this project. Study 1 (years 1-2), will collect EMA from 40 adolescents and examine the feasibility and acceptability of the CIR biomarker in the target sample. Study 2 (years 3-5), will implement a pilot RCT to test a contextually tailored, technology-enriched intervention in a sample of 70 adolescents, 12-16 years of age, from a low-income community in north Philadelphia. A 3-month behavioral intervention, including group-based sessions, interactive text messaging and parent support, will aim to reduce AS intake compared to an educational comparison group. Changes in AS, as measured by the CIR biomarker, will be assessed as the primary outcome and total changes in diet quality will be examined as a secondary outcome. A rigorous training plan complements the proposed research and is facilitated by mentors who are experts in nutrition, eating behavior, digital interventions, statistics, and behavioral trials in pediatric populations. Specific training objectives include: 1) ecological momentary assessment, 2) multi-level statistical modeling, 3) assessment of objective nutritional biomarkers and 4) designing and implementing behavioral interventions to address disparities. Temple University's Center for Obesity Research and Education is an ideal setting for this work as it provides extensive research resources and access to a population of diverse, high- risk youth. This award holds significant potential for public health impact and will enable Dr. Tripicchio to establish a rigorous program of research to improve dietary...