Using an integrated model of the extended theory of planned behavior and the temporal self-regulation theory to explain the sugar-sweetened beverage consumption in college students

Excessive consumption of sugar-sweetened beverages (SSBs) poses a significant threat to public health, with college students representing a major consumer group. Using the extended Theory of Planned Behavior (TPB) and Temporal Self-Regulation Theory (TST), this study examined the extent to which attitude, subjective norms, perceived behavioral control, delay discounting, habit, and self-control influence the intention and behavior of SSB consumption. A cross-sectional study was conducted in Jiangsu Province in 2024, involving 1236 college students. Data were collected using instruments based on the TPB-TST model, and delay discounting was assessed with a custom-designed computer program. Structural equation modeling was performed using Smart PLS software. The results showed that the integrated model explained 36.9 % of the variance in intention and 20.4 % in actual behavior. Delay discounting significantly influenced students' intention to consume SSBs. Attitudes, subjective norms, and perceived behavioral control also had significant positive effects on intention. Habit, self-control, and intention directly influenced SSB consumption, with habit moderating the intention-behavior relationship (β = -0.053, p < 0.05), weakening the impact of intention on behavior. In conclusion, the integration of the extended TPB and TST provides a robust framework for understanding SSB consumption among college students. Policy efforts and school-based interventions should target students' cognitive and psychological factors while regulating the availability of SSBs in campus environments to promote healthier behaviors. © 2025 Elsevier Ltd.