Technical Abstract: Background: Previous research supports a relationship between psychological stress and chronic disease, particularly in low-income minority populations. Stress may affect health, in part, through its influence on dietary and physical activity patterns. Objective: To probe this hypothesis, we examined relationships between perceived stress score, two hypothesized mediators of stress and effectors of food intake, insulin and cortisol, and dietary and activity patterns in Puerto Rican adults (age 45-75; 70% women) living in the Boston, Massachusetts area and participating in the Boston Puerto Rican Health Study. Design: Dietary intake, physical activity, serum insulin and urinary cortisol were determined in a cross-section of >1300 participants. Data were analyzed using multiple linear regression and ANCOVA. Results: A higher level of perceived stress was associated with lower intakes of fruit, vegetables, and protein, greater consumption of salty snacks and foods with high glycemic index, and lower participation in physical activity. Further, and particularly in those with type 2 diabetes, perceived stress was associated with higher intake of sweets. In those without diabetes, cortisol was higher in participants reporting more stress. Cortisol was associated with higher intake of saturated fat and, in those with diabetes, sweet foods. Stress was associated with higher circulating insulin, which was associated with more time watching television, but not with any of the examined dietary variables. Conclusion: Our findings suggest that stress, cortisol, and type 2 diabetes may interact to influence dietary and activity patterns in this population. Longitudinal research is needed to determine the causal pathway for these associations.