Behaviour Change

PROPAGANDA FOR CHANGE is a project created by the students of Behaviour Change (ps359) and Professor Thomas Hills @thomhills at the Psychology Department of the University of Warwick. This work was supported by funding from Warwick's Institute for Advanced Teaching and Learning.

Thursday, March 15, 2018

Do you eat enough vegetables? Probably not.

‘Have your 5 a day!’, ‘Eat your greens!’, ‘Spinach makes you strong!’

We all know that vegetables are good for us, but do we actually eat enough of them? Students are intelligent people, but university halls are packed full of ready meals and frozen chicken nuggets. We decided to try and change this, by giving students simple ways to incorporate vegetables into their meals.

Students don’t eat enough vegetables
From what we gathered from our everyday lives, a lot of our friends don’t eat vegetables, ever. However, we wanted to investigate whether this is true for most students.

·      Quantity
In a study by El Ansari et al (2011), they examined the eating behaviours of students at seven UK universities. They found that approximately 86% of the sample ate less than five portions of fruit and vegetables each day. According to a survey conducted in Northern Ireland by Devine, Lloyd and Gray (2006), 69% of students ate fresh vegetables and salad on only two or three days a week. 
Contrastingly, in Hong Kong, Lee and Loke (2005) found that 55% of female and 41% of male students ate between three and five portions of vegetables each day. This implies that there seems to be a problem with vegetable consumption among students in the UK.

·       Living away from home
In a study by El Ansari, Stock and Mikolajczyk (2012), their findings suggested that students living with their parents at home ate more vegetables than those that lived away from home. Additionally, Devine, Lloyd and Gray (2006) found that students living away from home were likely to eat fewer vegetables than they had a year earlier.

·      First years
Postgraduate students were more likely than first year students to eat enough vegetables and salad (Devine, Lloyd & Gray, 2006).

·    Stress
It has also been found that students show a decrease in ‘meal type’ foods (including vegetables) during stressful periods (Oliver & Wardle, 1999).

Students should eat vegetables

·      Health benefits
A lack of fruit and vegetables has been strongly linked to multiple serious health conditions. Vegetables provide essential nutrients such as vitamins, trace minerals, and fibre (Hanif, Iqbal, Iqbal, Hanif, & Rasheed, 2006) and it has been found that those who ate more vegetables had a lower risk of chronic disease (Lampe, 1999). High vegetable consumption has also been linked to a lower risk of certain cancers and cardiovascular diseases (Lundberg, Feelisch, Björne, Jansson, & Weitzberg, 2006), reduced coronary heart disease (Dauchet, Amouyel, Hercberg, & Dallongeville, 2006; Joshipura et al, 2001), and major reduction in strokes (He, Nowson, & MacGregor, 2006). All of these elements show how life changing a vegetable rich diet can be and why students should make an effort to increase their consumption.

·      Educational benefits
Research has also been conducted surrounding the importance of vegetables in regards to academic achievement in school children and university students. In one study (Logi Kristjánsson, Dóra Sigfúsdóttir, & Allegrante, 2010) good dietary habits were related to both high academic achievement and self-esteem, with fruit and vegetable consumption being highlighted as especially influential. Florence, Ashbridge, and Veugelers (2008) similarly found that poor diet quality was associated with poor academic achievement; again with an emphasis on fruit and vegetable consumption. These findings have also been seen in university students, with health, health awareness, and health behaviours strongly linked to educational achievement (El Ansari & Stock, 2010). This evidence again demonstrates that university students would benefit from increasing their vegetable consumption, in multiple ways.

What we did

In order to try and change the amount of vegetables that students eat, we created a poster and distributed it around campus. The poster is titled ‘Do you eat enough vegetables? Probably not.’ We included a statistic that ‘80% of adults eat less than the recommended amount of vegetables per day’ from a briefing by the Food Foundation in November 2016.  Underneath this are three ways for students to incorporate vegetables into their meals in an easy way. We put up these posters in different prime locations around campus.


·      The Elaboration Likelihood Model (Petty & Cacciopo, 1986)
Croll, Neumark-Sztainer, and Story (2001) found that adolescents do have knowledge about what healthy eating entails, but don’t act in accordance to this. This is partly due to lack of concern.  Therefore, we have used the peripheral route to persuasion, as the evidence has suggested that students seem to know that they should eat vegetables, but choose not to eat them, so the problem is not with their knowledge but with their motivation. Therefore, using an eye-catching poster would be more effective than using the central route as students already know they should eat vegetables. Firstly, the title of our poster is posed as a question, to grab an inattentive audience and make them think. Secondly, we used a statistic about the reality of the situation, which will possibly surprise and scare the audience. This was displayed very vividly on the poster in an eye catching way. As this campaign is in poster format, we knew people would not be paying great attention to it, and it will merely be viewed by those passing. This means they won’t have time to process lots of information, hence the decision to use predominantly the peripheral route.

·    Theory of Planned Behaviour (Ajzen, 1985)
This theory states that there are three elements that combine to produce someone’s intentions and behaviour. These are: attitude towards the behaviour, subjective norm, and perceived behavioural control. Our poster mainly attempts to implement the latter of these elements, but we will address all three.
·         Attitude: As we have stated, it seems that most people know that eating vegetables is good, so their attitude towards the behaviour should be reasonably positive already. Simply by seeing the poster we hope that people will be reminded of the issue and their positive attitude towards it, and this will enforce that attitude and hopefully increase the behaviour.
·         Subjective Norm: Our poster doesn’t attempt to show people that eating vegetables is the norm, it actually portrays the opposite. We state that not eating vegetables is more common, but hope that people will feel dissonance about this, as they know they should eat vegetables. Therefore, we hope that by showing people that most people (probably including them) don’t do this positive and important behaviour, those who see the poster will be shocked and try to change this.
·         Perceived Behavioural Control: This was the main component of this model we addressed. On the poster we included three practical ideas for how to increase one’s vegetable consumption in day to day life. By giving these specific and simple suggestions, we hope that people will feel that it is easy to change their eating behaviours and therefore feel that they have control over their diet. According to the model, this should increase the behaviour we are trying to encourage. 


We hope that the posters will be viewed by many students as they pass them and this will affect at least some people’s eating habits. Hopefully our posters will remind students to think about their eating habits, increasing awareness and eventually resulting in some behaviour change. Unfortunately, we are unable to measure any potential behaviour change resulting from our project. However, as we have given people easy suggestions as to how to implement the behaviour change we are hoping to see, we feel this will make it easier for them to do so.

Remember to eat your greens!


Ajzen, I. (1985). From intentions to actions: A theory of planned behavior. In Action control (pp. 11-39). Springer Berlin Heidelberg.
Croll, J. K., Neumark-Sztainer, D., & Story, M. (2001). Healthy eating: what does it mean to adolescents?. Journal of nutrition education, 33(4), 193-198.
Dauchet, L., Amouyel, P., Hercberg, S., & Dallongeville, J. (2006). Fruit and vegetable consumption and risk of coronary heart disease: a meta-analysis of cohort studies. The Journal of nutrition, 136(10), 2588-2593.
Devine, P., Lloyd, K., & Gray, A. M. (2006). University Student Food Attitudes and Behaviour Survey. Northern Ireland Social and Political Archive, 61-70.
El Ansari, W., Stock, C., John, J., Deeny, P., Phillips, C., Snelgrove, S., ... & Mabhala, A. (2011). Health promoting behaviours and lifestyle characteristics of students at seven universities in the UK. Central European journal of public health19(4), 197.
El Ansari, W., & Stock, C. (2010). Is the health and wellbeing of university students associated with their academic performance? Cross sectional findings from the United Kingdom. International journal of environmental research and public health, 7(2), 509-527.
El Ansari, W., Stock, C., & Mikolajczyk, R. T. (2012). Relationships between food consumption and living arrangements among university students in four European countries-a cross-sectional study. Nutrition journal11(1), 28.
Florence, M. D., Asbridge, M., & Veugelers, P. J. (2008). Diet quality and academic performance. Journal of school health, 78(4), 209-215.
Hanif, R., Iqbal, Z., Iqbal, M., Hanif, S., & Rasheed, M. (2006). Use of vegetables as nutritional food: role in human health. J Agric Biol Sci, 1(1), 18-22.
He, F. J., Nowson, C. A., & MacGregor, G. A. (2006). Fruit and vegetable consumption and stroke: meta-analysis of cohort studies. The Lancet, 367(9507), 320-326.
Joshipura, K. J., Hu, F. B., Manson, J. E., Stampfer, M. J., Rimm, E. B., Speizer, F. E., ... & Willett, W. C. (2001). The effect of fruit and vegetable intake on risk for coronary heart disease. Annals of internal medicine, 134(12), 1106-1114.
Lampe, J. W. (1999). Health effects of vegetables and fruit: assessing mechanisms of action in human experimental studies–. The American journal of clinical nutrition, 70(3), 475s-490s.
Lee, R. L., & Loke, A. J. (2005). Health‐promoting behaviors and psychosocial well‐being of university students in Hong Kong. Public health nursing22(3), 209-220.
Logi Kristjánsson, Á., Dóra Sigfúsdóttir, I., & Allegrante, J. P. (2010). Health behavior and academic achievement among adolescents: the relative contribution of dietary habits, physical activity, body mass index, and self-esteem. Health Education & Behavior, 37(1), 51-64.
Lundberg, J. O., Feelisch, M., Björne, H., Jansson, E. Å., & Weitzberg, E. (2006). Cardioprotective effects of vegetables: is nitrate the answer?. Nitric Oxide, 15(4), 359-362.
Oliver, G., & Wardle, J. (1999). Perceived effects of stress on food choice. Physiology & behavior, 66(3), 511-515.
Petty, R. E., & Cacioppo, J. T. (1986). The elaboration likelihood model of persuasion. In Communication and persuasion (pp. 1-24). Springer New York.

Annabel Moore and Claire Slater

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.