Planning and self-efficacy can increase fruit and vegetable consumption: a randomized controlled trial

Abstract

Fruit and vegetable consumption represents a nutritional goal to prevent obesity and chronic illness. To change dietary behaviors, people must be motivated to do so, and they must translate their motivation into actual behavior. The present experiment aims at the psychological mechanisms that support such changes, with a particular focus on dietary self-efficacy and planning skills. A randomized controlled trial compared a theory-based psychological intervention with a health education session in 114 participants. Dependent variables were fruit and vegetable consumption, intention to consume more fruit and vegetables, planning to consume more, and dietary self-efficacy, assessed before the intervention, 1 week afterwards, and at 6-week follow up. Significant group by time interactions for all four dependent variables documented superior treatment effects for the psychological intervention group, with substantially higher scores at posttest and follow-up for the experimental group, although all students benefited from participation. To identify the contribution of the main intervention ingredients (self-efficacy and planning), regression analyses yielded mediator effects for these two factors. A social-cognitive intervention to improve fruit and vegetable consumption was superior to a knowledge-based education session. Self-efficacy and planning seem to play a major role in the mechanisms that facilitate dietary changes.

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References

  1. Armitage, C. J. (2004). Evidence that implementation intentions reduce dietary fat intake: A randomized trial. Health Psychology, 23, 319–323.

    PubMed  Article  Google Scholar 

  2. Ball, K., MacFarlane, A., Crawford, D., Savige, G., Andrianopoulos, N., & Worsley, A. (2009). Can social cognitive theory constructs explain socio-economic variations in adolescent eating behaviours? A mediation analysis. Health Education Research, 24, 496–506.

    PubMed  Article  CAS  Google Scholar 

  3. Bandura, A. (1997). Self-efficacy: The exercise of control. New York: Freeman.

    Google Scholar 

  4. Betts, N. M., Amos, R. J., Georgiou, C., Hoerr, S. L., Ivaturi, R., Keim, K. S., et al. (1995). What young adults say about factors affecting their food intake. Ecology of Food and Nutrition, 34, 59–64.

    Article  Google Scholar 

  5. Betts, N. M., Amos, R. J., Keim, K., Peters, P. K., & Stewart, B. (1997). Ways young adults view foods. Journal of Nutrition Education, 29, 73–79.

    Article  Google Scholar 

  6. Brown, L. B., Dresen, R. K., & Eggett, D. L. (2005). College students can benefit by participating in a prepaid meal plan. Journal of the American Dietetic Association, 105, 445–448.

    PubMed  Article  Google Scholar 

  7. Brug, J., Lechner, L., & De Vries, H. (1995). Psychosocial determinants of fruit and vegetable consumption. Appetite, 25, 285–296.

    PubMed  Article  CAS  Google Scholar 

  8. Chapman, J., Armitage, C. J., & Norman, P. (2009). Comparing implementation intention interventions in relation to young adults’ intake of fruit and vegetables. Psychology & Health, 24, 317–332.

    Article  Google Scholar 

  9. Chung, S. J., & Hoerr, S. L. (2005). Predictors of fruit and vegetable intakes in young adults by gender. Nutrition Research, 25, 453–463.

    Article  CAS  Google Scholar 

  10. De Bruijn, G. J. (2010). Understanding college students’ fruit consumption. Integrating habit strength in the theory of planned behaviour. Appetite, 54, 16–22. doi:10.1016/j.appet.2009.08.007

    PubMed  Article  Google Scholar 

  11. de Vet, E., de Nooijer, J., de Vries, N. K., & Brug, J. (2008). Testing the Transtheoretical model for fruit intake: Comparing web-based tailored stage-matched and stage-mismatched feedback. Health Education Research, 23, 218–227. doi:10.1093/her/cym019

    PubMed  Article  Google Scholar 

  12. Franko, D. L., Cousineau, T. M., Trant, M., Green, T. C., Rancourt, D., Thompson, D., et al. (2008). Motivation, self-efficacy, physical activity and nutrition in college students: Randomized controlled trial of an internet-based education program. Preventive Medicine, 47, 369–377.

    PubMed  Article  Google Scholar 

  13. Gollwitzer, P. M., & Sheeran, P. (2006). Implementation intentions and goal achievement: A meta-analysis of effects and processes. Advances in Experimental Social Psychology, 38, 69–119.

    Article  Google Scholar 

  14. Gratton, L., Povey, R., & Clark-Carter, D. (2007). Promoting children’s fruit and vegetable consumption: Interventions using the Theory of Planned Behaviour as a framework. British Journal of Health Psychology, 12, 639–650.

    PubMed  Article  Google Scholar 

  15. Gutiérrez-Doña, B., Lippke, S., Renner, B., Kwon, S., & Schwarzer, R. (2009). How self-efficacy and planning predict dietary behaviors in Costa Rican and South Korean women: A moderated mediation analysis. Applied Psychology: Health & Well-Being, 1, 91–104. doi:10.1111/j.1758-0854.2009.01004.x

    Article  Google Scholar 

  16. Ha, E. J., & Caine-Bish, N. (2009). Effect of nutrition intervention using a general nutrition course for promoting fruit and vegetable consumption among college students. Journal of Nutrition Education and Behavior, 41, 103–109.

    PubMed  Article  Google Scholar 

  17. Hayes, A. F. (2009). Beyond Baron and Kenny: Statistical mediation analysis in the new millennium. Communication Monographs, 76, 408–420. doi:10.1080/03637750903310360

    Article  Google Scholar 

  18. Health Information System Development Office (HISO). (2006). Health status report of Thailand (in Thai). Nonthaburi, Thailand: Thai Health Promotion Foundation.

    Google Scholar 

  19. Hunter, W., McNaughton, S., Crawford, D., & Ball, K. (2010). Does food planning mediate the association between living arrangements and fruit and vegetable consumption among women aged 40 years and older? Appetite, 54, 533–537.

    PubMed  Article  Google Scholar 

  20. Kellar, I., & Abraham, C. (2005). Randomized controlled trial of a brief research-based intervention promoting fruit and vegetable consumption. British Journal of Health Psychology, 10, 543–558.

    PubMed  Article  Google Scholar 

  21. Lippke, S., & Ziegelmann, J. P. (2008). Theory-based health behavior change: Developing, testing and applying theories for evidence-based interventions. Applied Psychology, 57, 698–716. doi:10.1111/j.1464-0597.2008.00339.x

    Article  Google Scholar 

  22. Luszczynska, A., Tryburcy, M., & Schwarzer, R. (2007). Improving fruit and vegetable consumption: A self-efficacy intervention compared to a combined self-efficacy and planning intervention. Health Education Research, 22, 630–638.

    PubMed  Article  Google Scholar 

  23. MacKinnon, D. (2008). Statistical mediation analysis. New York: Erlbaum.

    Google Scholar 

  24. Ministry of Public Health (MOPH). (2000a). Health behaviors and physical activity practices among employees within the Ministry of Public Health (in Thai). Nonthaburi, Thailand: Physical Activity Division, Ministry of Public Health.

    Google Scholar 

  25. Ministry of Public Health (MOPH). (2000b). Nutrition flag manual (in Thai). Nonthaburi, Thailand: Department of Health, Ministry of Public Health.

    Google Scholar 

  26. Neumark-Sztainer, D., Wall, M., Perry, C., & Story, M. (2003). Correlates of fruit and vegetable intake among adolescents Findings from Project EAT. Preventive Medicine, 37, 198–208.

    PubMed  Article  Google Scholar 

  27. Preacher, K. J. & Hayes, A. F. (2008). Asymptotic and resampling strategies for assessing and comparing indirect effects in multiple mediator models. Behavior Research Methods, 40(3), 879–891.

    Google Scholar 

  28. Renner, B., Kwon, S., Yang, B.-H., Paik, K.-C., Kim, S. H., Roh, S., et al. (2008). Social-cognitive predictors of dietary behaviors in South Korean men and women. International Journal of Behavioral Medicine, 15, 4–13.

    PubMed  Article  Google Scholar 

  29. Reuter, T., Ziegelmann, J. P., Wiedemann, A. U., & Lippke, S. (2008). Dietary planning as a mediator of the intention-behavior relation: An experimental-causal-chain design. Applied Psychology. Special Issue: Health and Well-Being, 57, 194–207.

    Google Scholar 

  30. Richert, J., Reuter, T., Wiedemann, A. U., Lippke, S., Ziegelmann, J., & Schwarzer, R. (2010). Differential effects of planning and self-efficacy on fruit and vegetable consumption. Appetite, 54, 611–614. doi:10.1016/j.appet.2010.03.006

    PubMed  Article  Google Scholar 

  31. Satheannoppakao, W., Aekplakorn, W., & Pradipasen, M. (2009). Fruit and vegetable consumption and its recommended intake associated with sociodemographic factors: Thailand National Health Examination Survey III. Public Health Nutrition, 12(11):2192–2198.

    Google Scholar 

  32. Schwarzer, R. (2008). Modeling health behavior change: How to predict and modify the adoption and maintenance of health behaviors. Applied Psychology, 57, 1–29. doi:10.1111/j.1464-0597.2007.00325.x

    Google Scholar 

  33. Schwarzer, R., Lippke, S., & Luszczynska, A. (2011). Mechanisms of health behavior change in persons with chronic illness or disability: The health action process approach (HAPA). Rehabilitation Psychology. doi:10.1037/a0024509.

  34. Shaikh, A. R., Yaroch, A. L., Nebeling, L., Yeh, M. C., & Resnicow, K. (2008). Psychosocial predictors of fruit and vegetable consumption in adults: A review of literature. American Journal of Preventive Medicine, 34, 535–543.

    PubMed  Article  Google Scholar 

  35. Sniehotta, F. F. (2009). Towards a theory of intentional behaviour change: Plans, planning and self-regulation. British Journal of Health Psychology, 14, 261–273.

    PubMed  Article  Google Scholar 

  36. Sniehotta, F. F., Schwarzer, R., Scholz, U., & Schüz, B. (2005). Action planning and coping planning for long-term lifestyle change: Theory and assessment. European Journal of Social Psychology, 35, 565–576.

    Article  Google Scholar 

  37. Stadler, G., Oettingen, G., & Gollwitzer, P. M. (2010). Intervention effects of information and self-regulation on eating fruits and vegetables over two years. Health Psychology, 29(3), 274–293.

    PubMed  Article  Google Scholar 

  38. Wiedemann, A. U., Lippke, S., Reuter, T., Ziegelmann, J. P., & Schüz, B. (2011). The more the better? The number of plans predicts health behaviour change. Applied Psychology: Health and Well-Being, 3, 87–106. doi:10.1111/j.1758-0854.2010.01042.x

  39. Wiedemann, A. U., Lippke, S., & Schwarzer, R. (2011). Multiple plans and memory performance: Results of a randomized controlled trial targeting fruit and vegetable intake. Journal of Behavioral Medicine. Published online 25 June 2011. doi: 10.1007/s10865-011-9364-2

  40. World Health Organization (WHO). (2003). Diet, nutrition and the prevention of chronic diseases (Report of a Joint WHO/FAO Expert Consultation. WHO Technical Report Series No. 916). Retrieved from https://www.who.int/dietphysicalactivity/publications/trs916/en/gsfao_introduction.pdf.

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Correspondence to Ralf Schwarzer.

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Kreausukon, P., Gellert, P., Lippke, S. et al. Planning and self-efficacy can increase fruit and vegetable consumption: a randomized controlled trial. J Behav Med 35, 443–451 (2012). https://doi.org/10.1007/s10865-011-9373-1

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Keywords

  • Fruit and vegetable consumption
  • Self-efficacy
  • Intentions
  • Planning
  • Dietary changes