Hidden Risks of Ultra-Processed Foods: How Health and Environmental Risk Perceptions Drive Sustainable Dietary Intentions in Taiwan

Background/Objective: Ultra-processed foods (UPFs) have become deeply embedded in global dietary patterns. However, their widespread consumption conceals the dual hidden risks of delayed physiological health effects and long-overlooked environmental externalities. Prior research has largely centered on health-driven dietary behaviors, with insufficient understanding of how perceptions of the environmental burden shape consumer choices, particularly in highly convenient, eating-out-dominated food environments. To address this gap, this study extends the theory of planned behavior (TPB) to examine how dual-risk perceptions influence intentions to reduce UPF consumption. Methods: Drawing on survey data from 362 Taiwanese consumers, this study analyzed the proposed theoretical model using structural equation modeling. Results: The findings show that (1) both health and environmental risk perceptions significantly and positively shape attitudes toward reducing UPF intake; (2) attitude, subjective norms, and perceived behavioral control (PBC) significantly increase reduction intentions, with subjective norms and attitude emerging as the strongest predictors; and (3) environmental awareness produces a counterintuitive diminishing marginal effect, negatively moderating the relationship between environmental burden perception and behavioral intention. Conclusions: These results extend the empirical foundation of the “green TPB” by demonstrating that the internalization of environmental costs complements traditional health motivations. The findings offer actionable implications for public health policy, including the implementation of front-of-pack warning labels and the use of the NOVA food classification system to advance sustainable diets.