Previous studies have documented that early adversity increases young adults’ risk for diabetes resulting in morbidity and comorbidity with adverse health conditions. However, less is known about how inter-related physiological (e.g., body mass index [BMI]), psychological (e.g., depressive symptoms), and behavioral mechanisms (e.g., unhealthy eating and sedentary behavior) link early adversity to young adults’ diabetes outcomes, although these mechanisms appear to stem from early stressful experiences. The current study tested the patterning of these longitudinal pathways leading to young adults’ diabetes using a nationally representative sample of 13,286 adolescents (54% female) over a period of 13 years. The findings indicated that early adversity contributed to elevated BMI, depressive symptoms, and stress-related health behaviors. The impact of these linking mechanisms on hierarchical diabetes outcomes (i.e., prediabetes and diabetes) remained significant after taking their associations with each other into account, showing that these mechanisms operate concurrently. The findings emphasize the importance of early detection for risk factors of young adults’ diabetes in order to minimize their detrimental health effects.