Background/Objectives: Adherence to the Mediterranean Diet (MD) is associated with substantial physical and psychological health benefits, yet its adoption remains challenging during emerging adulthood. Although previous research has identified motivational and socio-cognitive determinants of specific eating behaviors, less is known about the psychological processes underlying adherence to the MD as a whole in youth. The present study examined the role of motivational factors derived from Self-Determination Theory (SDT) and key socio-cognitive variables from the Theory of Planned Behavior (TPB) in explaining adherence to the MD in young adults. Methods: A sample of 365 young adults (50.1% female; mean age = 21.74 years, SD = 5.86) completed an online questionnaire assessing motivational regulations, perceived behavioral control (PBC), behavioral intention, and adherence to the MD. Results: Structural equation modeling showed an excellent fit of the hypothesized model. Adherence to the MD was directly associated with behavioral intention (β = 0.18, p < 0.05), PBC (β = 0.24, p < 0.01), and intrinsic motivation (β = 0.22, p < 0.05). Behavioral intention was positively associated with PBC (β = 0.48, p < 0.001) and intrinsic motivation (β = 0.21, p < 0.05) and negatively associated with amotivation (β = −0.23, p < 0.05). Integrated regulation showed a significant indirect effect on intention via PBC. The model accounted for 40% of the variance in intention and 16% of the variance in adherence. Conclusions: The results suggest that interventions targeting this population should strengthen dietary intentions, enhance PBC, and foster autonomous motivation. The integrated model provides a useful framework for designing healthcare and public health interventions aimed at promoting healthy eating during emerging adulthood.
Gentile et al. (Tue,) studied this question.