De Bruijn, G. J., Kremers, S. P. J., De Vries, H., Van Mechelen, W., & Brug, J. (2007). Associations of social-environmental and individual-level factors with adolescent soft drink consumption: results from the SMILE study. Health Education Research, 22, 227-237.

Abstract: Adolescent obesity is positively associated with soft drink consumption. We investigated the association of social-environmental and individual-level factors with soft drink consumption in a Dutch adolescent sample. Data were gathered in a longitudinal Dutch adolescent sample (n = 208, 62% girls). Soft drink consumption, social cognitions from the Theory of Planned Behaviour and parenting practices towards limited soft drink intake, and Big Five personality dimensions were assessed. Data were analyzed using three-step linear regression analyses. Effect sizes were used as the informational source for the explanatory value of the model. Interaction terms were computed to test the individual-environment interaction. Attitude and subjective norm were significantly associated with soft drink consumption. When controlling for social cognitions, the distal variables parenting practices and the personality dimension Agreeableness remained significantly associated with soft drink consumption. Agreeableness moderated the association of parenting practices with adolescent soft drink consumption. Standardized regression coefficients ranged from 0.16 to 0.24 and explained 14% of the variance in soft drink consumption, indicating a medium effect size. Stricter parenting practices were associated with less soft drink consumption and these effects were moderated by adolescent personality. The direct effects of practices and personality are noteworthy from a theoretical perspective. Implications for obesity prevention interventions are discussed.