Latinos are disproportionately affected by multiple chronic diseases, including obesity, type 2 diabetes (T2D), non-alcoholic fatty liver disease (NAFLD), and dyslipidemia, and this begins in early life. Understanding and eliminating these disparities is a national priority given the clinical and public health burden associated with these co-existing chronic diseases. Our work over the last 20 years in Latino infants and children has identified 3 recurring risk factors for these chronic diseases that emerge early in life: 1) formula feeding rather than breastfeeding, as well as formula type (i.e., formula with added sugar); 2) early introduction of sugar sweetened beverages and juices (SSB/J), and 3) environmental exposure to air pollution. Despite this, prior work in young Latino children is limited to assessment of obesity outcomes based on height and weight and lacks robust measures of adiposity and other sub-clinical markers of future chronic disease risk. In addition, no prior study has holistically examined these risk factors in the context of broader environmental factors and social determinants of health (SDOH) that may exacerbate their impact on health outcomes. We propose a comprehensive study in Latino children to examine the contributions of early-life nutrition, exposure to environmental toxins, and SDOH on subclinical markers of chronic disease risk at 5y of age. We will leverage 2 NIH-funded birth cohorts led by Dr. Goran (R01DK110793; R01DK109161), which have already thoroughly characterized early-life exposures in Latino infants from Los Angeles County, with repeated assessments in the first 2y of life. We will combine these cohorts and collect new outcome measures at 5y of age in the proposed Early Life Social, Environmental, and Nutritional Determinants of Disease (ELSEND) study. In ELSEND, we will collect follow-up measures from 190 children at 5y of age using robust subclinical markers of progressive disease, including non-invasive assessments of fat distribution by magnetic resonance imaging (MRI), liver fat and fibrosis by MRI and elastography, and blood glucose regulation by continuous glucose monitoring (CGM) over 7 days. We will update nutritional information and current and cumulative environmental exposures (air pollution, CalEnviroScreen Index), and will collect new data on broader SDOH, including geospatial assessments of social and structural factors such as the neighborhood and built environment. This project will address the following aims: 1) Assess whether early nutrition and/or exposure to environmental toxins is associated with child growth and/or risk for chronic disease at age 5y; 2) Assess if the food environment and broader SDOH is associated with subclinical markers of disease and if they exacerbate the adverse effects of poor nutrition and/or environmental toxins. In addition, by combining data from children across all 3 Center projects, we will also examine the associations between social and environmental exposures and childhood diet with risk factors for chronic disease in 530 children across Southern California, and explore whether the efficacy of 3 different family- based interventions is impacted by individual and/or community level environmental factors.