Effects of Self-Efficacy on Healthy Eating Depends on Normative Support: a Prospective Study of Long-Haul Truck Drivers
- 192 Downloads
Fruit and vegetable intake (FV) is insufficient in industrialized nations and there is excess of discretionary food choices (DC; foods high in fat, sugar, and salt). Long-haul truck drivers are considered a particularly at-risk group given the limited food choices and normatively reinforced eating habits at truck rest-stops. Self-efficacy and normative support are key determinants of eating behavior yet the processes underlying their effects on behavior are not well understood. We tested the direct and interactive effects of self-efficacy and normative support on healthy eating behaviors in long-haul truck drivers in a prospective correlational study.
Long-haul truck drivers (N = 82) completed an initial survey containing self-report measures of behavioral intentions, perceived normative support, and self-efficacy for their FV and DC behaviors. Participants completed a follow-up survey 1 week later in which they self-reported their FV and DC behavior.
A mediated moderation analysis identified an interactive effect of self-efficacy and normative support on behavior mediated by intention for FV and DC behavior. Specifically, we confirmed a compensation effect in which self-efficacy was more likely to have an effect on FV and DC behavior through intentions in participants with low normative support.
Results indicate the importance of self-efficacy in predicting FV and DC intentions and behavior in the absence of a supportive normative environment. The compensatory effect of self-efficacy beliefs on behavior through intentions when normative support is low should be confirmed using experimental methods.
KeywordsSelf-confidence Social support Group norms Fruit and vegetable intake Discretionary choices Nutrition
We thank Caitlin Vayro and Daniel Brown for their help in data collection.
Martin S. Hagger’s contribution was supported by a Finland Distinguished Professor (FiDiPro) award from Tekes, a Finnish funding agency for innovation.
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Informed consent was obtained from all individual participants included in the study.
- 1.Katz DL, Meller S. Can we say what diet is best for health? Annu Rev Public Health. 2014;24:83–103. https://doi.org/10.1146/annurev-publhealth-032013-182351.CrossRefGoogle Scholar
- 2.WHO. Obesity and overweight. Geneva: World Health Organization; 2016. Retreived from http://www.who.int/mediacentre/factsheets/fs311/en/ Google Scholar
- 3.WHO. Healthy diet. Geneva: World Health Organization; 2015. Retreived from http://www.who.int/mediacentre/factsheets/fs394/en/ Google Scholar
- 4.NHMRC. Australian dietary guidelines. Canberra: National Health and Medical Research Council; 2013.Google Scholar
- 7.Bandura A. Self-efficacy: the exercise of control. New York: Freeman; 1997.Google Scholar
- 8.Burg J. Determinants of healthy eating: motivation, abilities and environmental opportunities. Fam Pr. 2008;25:150–5.Google Scholar
- 15.Hamilton K, Kirkpatrick A, Rebar A, Hagger MS. Child sun safety: application of an integrated behavior change model. Health Psychol. 2017; https://doi.org/10.1037/hea0000533.
- 18.Stevenson M, Sharwood LN, Wong K, Elkington J, Meuleners L, Ivers RQ, et al. The heavy vehicle study: a case-control study investigating risk factors for crash in long distance heavy vehicle drivers in Australia. BMC Pub Health. 2010;10:162. https://doi.org/10.1186/1471-2458-10-162.CrossRefGoogle Scholar
- 20.Hayes AF. Introduction to mediation, moderation, and conditional process analysis: a regression-based approach. Methodology in the social sciences. New York: Guildford Press; 2013.Google Scholar
- 22.Hagger MS, Luszczynska A, de Wit J, Benyamini Y, Burkert S, Chamberland P-E, et al. Implementation intention and planning interventions in health psychology: recommendations from the synergy expert group for research and practice. Psychol Health. 2016;31:814–39. https://doi.org/10.1080/08870446.2016.1146719.CrossRefPubMedGoogle Scholar