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Supporting healthy behaviour. A stages of change perspective on changing
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Conference Paper · June 2016
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Supporting healthy behaviour; A stages of change perspective on changing snacking habits of children
Geke D.S. Luddena*, Laura H.J. de Ruijtera aUniversity of Twente, Department of Design *Corresponding author e-‐mail: [email protected]
Abstract: Many children today face an environment that presents them with an overabundance of high calorie foods. Combined with more sedentary lifestyles, this has led to increasing numbers of overweight children in many parts of the world. To counter this trend, we need new strategies that can positively alter health behaviours of children. In this paper, we demonstrate how taking a stages of change perspective can support designers in creating products and services that could serve as alternatives to more traditional health interventions such as promotional campaigns. Using the case of changing snacking habits of children, two ranges of product concepts were developed using the design for healthy behaviour framework. The two concept ranges were evaluated by parents of young children. From this study we tentatively conclude that using the design for healthy behaviour framework can lead to more innovative, supporting and effective health interventions.
Keywords: design for behaviour change; health; obesity; lifestyle; children
1. Introduction Anyone who has ever gone grocery shopping with a child has probably experienced how successful the food industry currently is in creating attractive but not so healthy snacks for children by, for example, linking them to popular cartoon figures. Studies have suggested that commercials increase preferences of children aged 3-‐4 years for advertised foods and that children who are frequently exposed to television are more likely to have unhealthy ideas about nutrition (Signorielli & Staples, 1997). Recently, there has been a debate about snacks (‘in-‐between-‐meals’) raised by the Dutch Centre for Nutrition. They claimed that ‘snacks’ were merely invented by the food industry, adding to the growing problem of obesity by offering people an easy (and apparently normal) way to make it a habit to eat too many calories every day. In a study on the relation between dietary variety and body fatness in men and women, Mc Crory et al (1999) found that the number of new food products
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introduced to the US food market classified as condiments, candy, snacks and bakery foods parallels the increasing prevalence of obesity. Moreover, snacks especially targeted at children often contain too many calories and are often less healthy than could be expected based on the information provided on the package or in advertisements. For example, cookies for children are often packed per two or three, portions that are just too large for young children. Also, snacks such as yoghurt raisins may seem healthy but they contain unhealthy coatings made of oil and sugar and only contain 1% yoghurt powder. The developments sketched above describe an environment where children face an overabundance of high calorie foods and where learning how to live a healthy lifestyle is a growing challenge. In her review article on obesity prevention in children, Melinda Sothern (2004) advocates to involve both parents and schools to increase awareness and promote environments that encourage physical activity and healthy nutrition.
Traditionally, raising awareness of health issues has taken the form of campaigns targeted at, for example, eating fruit and vegetables. Although these health interventions in some cases do raise awareness of the health issues that many people face, it is questionable if they will eventually help people to actively change their eating habits. In recent years, more innovative means of designing for healthy behaviour have been sought, that include monitoring and coaching systems that allow people to track their daily intake of food. We have argued before (Ludden & Hekkert, 2014) that such systems could offer valuable feedback but it generally is quite tiresome to use them for longer periods of time. Therefore, we have argued that designing for stages of change can support designers to guide people through a process of behaviour change in order to sustainably change their health behaviour. In this paper, we will apply the design for healthy behaviour framework that we have developed (Ludden & Hekkert, 2014) to the case of changing snacking habits of children and their parents. As such, this paper has two main aims. First, it will serve as a demonstration on how the design for healthy behaviour framework can be used as a design guideline. Secondly, we will evaluate to what extent the products and services that were designed are indeed particularly suitable for (and preferred by) people in specific stages of change.
In the next section, we will explain the design for healthy behaviour framework in more detail. The paper will continue to discuss the design of two concept ranges designed to support children and their parents to acquire healthier snacking habits. Next, we will present an online study that evaluated the designed concepts. Results of this study will be presented and discussed in relation to the design for healthy behaviour framework.
2. Design for stages of change From their work on health behaviour change, Prochaska and colleagues (Prochaska et al., 1992; 1997) developed the Transtheoretical Model of Health Behaviour Change (TTM). Prochaska et al. suggest that to make a durable health change, whether it is to quit smoking or to eat a healthier diet, people pass through five stages: precontemplation, contemplation,
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preparation, action and maintenance. In the first three stages people built motivation to change and in the last two stages people act. Following this theory, health interventions should have different goals for people who are in different stages of change. While interventions aimed at early stages of change should aim to raise awareness, interventions in later stages should be more focused on acting out and sustaining new behaviour.
Following a study of existing health interventions in the product and service domain (Ludden & Hekkert, 2014), we have proposed the design for healthy behaviour framework that combines processes of change and stages of change with design strategies. Figure 1 shows the relationships between these concepts. In the design for healthy behaviour framework four types of design strategies have been defined that correspond with four different (design) aims: ‘raising awareness’, ‘enabling’, ‘motivating’ and ‘fading out’. These design strategies spread over multiple stages. For the present study, this framework was the starting point for the design of products and services that support children and their parents to adopt healthier snacking behaviour.
2.1 Design of stage-‐matched health interventions Two concept ranges were designed that each consisted of four separate products. For each of the concept ranges, one concept was designed that would serve as the trigger (first encounter in a public environment, see also Ludden & Offringa (2015)) for a range, one of the products was designed following the design strategy ‘raising awareness’ (addressing the earlier stages of change pre-‐contemplation and contemplation), one was designed following the strategy ‘enabling’ (addressing the middle stages of change preparation and into action) and one was designed following the strategy of motivation (addressing the later stages of change action and maintenance). For this study, we did not design interventions following the ‘fading out’ strategy. Educating parents on child nutrition has been identified as an effective strategy to adopt healthy eating habits (Schonfeld-‐Warden & Warden, 1997). Alternatively, interventions aimed at children have often tried to implement elements of fun and gaming to motivate children to use them. To be able to explore the benefits of each of these approaches, we decided to develop one of the concept ranges with a focus on providing knowledge and information on healthy snacking, while the other concept range was focused on making healthy snacking more fun.
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To make sure the products within one range were coherent, they were based on similar stories and also the graphic representation was consistent. Figure 2 shows the two ranges of products that were designed for this study. Because the purpose of these concepts was to evaluate them in an online survey the designs were made into annotated sketches that could explain how the product would be used (see Figure 3 to 6). In the following sections we will elaborate on the design of the two concept ranges.
Figure 2 Two ranges of products were designed that each included a trigger for a public environment and three products that spanned the stages of change from (pre-‐) contemplation to maintenance. Within the concept ranges, products were based on the same theme, the two themes were: ‘My body as a factory’ and ‘Healthy food made fun’.
2.2 Concept range 1: My body is a factory Concept range 1 introduces the story of seeing the body as a factory that can only work well when healthy food enters. The first product is a game that children can play at school (see Figure 3). The game board resembles a child’s body that needs healthy food to light the lamps. By placing the display parts of a factory on the body and by connecting pawns that display various types of snacks in the holes, LEDs shaping a mouth for the figure will start glowing. When healthy food is placed on the body the figure smiles, but when unhealthy food enters the factory the figure looks sad.
The second product in the ‘My body as a factory’ range is a mobile application in which a child-‐like figure can be seen (See Figure 3). The child can reconfigure the virtual figure to his or her liking and give the figure the same snacks as the child itself has eaten during the day. The figure then shows the influence that the snack has on him/her: if the figure ‘eats’ healthy snacks it will have enough energy and be happy. If the figure has been eating too many unhealthy snacks, it will be less energetic and sad. The child will be reminded that maybe the figure needs to be more active.
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Figure 3 The trigger product (left) in the theme ‘My body is a factory’ is an educational game children play at school. The product targeting the first strategy raising awareness is a mobile application.
The third concept in the ‘My body as a factory’ range consists of a book and a plate (see Figure 4). The book describes the adventures of little workers that clean up in the factory that is the child’s body. The general message in these stories is that the child’s body needs healthy nutrition to be able to play. The plate combines a small bowl for chopped, healthy snacks with the representation of a factory. The child can play with the food in the factory while listening to the story and, of course, enjoy eating the snack. In this way, eating a healthy snack is enabled and can be a more enjoyable experience.
Figure 4 The third product in the theme ‘My body is a factory’ (left hand image) is a book with stories that is combined with a plate designed to enable healthy snacking. The fourth and last product in this theme (right hand image) is a tower where parents can store healthy snacks.
The fourth and last concept in this range is a tower to store and make available healthy snacks (See Figure 4). The child is free to take food from the lower sections of the tower and has to ask permission to take food from the upper parts of the tower.
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2.3 Range 2: Healthy food made fun The first product in this concept range, which can serve as a trigger, is a carton box (placed in or handed out in a supermarket) containing different pieces of fruit that can be used to create fruit-‐art birthday treats (see Figure 5). This box is attractive for children because it displays colourful drawings, and it is attractive for parents because it offers them an easy way to make a healthy birthday treat. On the box, there is a code that unlocks the first level of the second product in the sequence: a mobile application that shows parents information about healthy snacking, offers them they opportunity to track what snacks the family eats and offers new ways to make eating fruit more fun (see Figure 5). The parent can use other codes from separate fruit boxes to unlock new levels in the application.
Figure 5 The first product, the trigger, in the ‘Healthy food made fun’ range (left hand image) is a
carton box that contains tools and fruit or vegetables to create food art. The second product in this range (right hand image) combines physical products (fruit boxes) with a mobile application.
Higher levels in the application give parents access to the third product in the sequence which is a series of rubber tools that come in different shapes (for example a palm tree or a peacock, as displayed in Figure 6) and that enable the parents to quickly and easily make attractive fruit art for their children to bring to school. The fourth concept in this range was designed to motivate when eating fruit and vegetables already is part of the normal daily routine of children and parents (see Figure 6). It is a mobile application for tablet or smart phone that has multiple functions: first of all, the child can fill in the snacks it has eaten on a specific day and feedback will be displayed on how healthy the combination was by the representation of a healthy or not so healthy flower. Next to this, the application contains stories that explain the origin of certain fruits and vegetables. In addition, it provides examples of how fruit or vegetables can attractively be presented to a child. Figure 6 shows the example of a story about the orange of carrots related to the Dutch royal family.
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Figure 6 The third product in the theme ‘Healthy food made fun’ (left hand image) is a series of rubber tools that parents can use to create fruit art. The fourth and last product in this series (right hand image) is a mobile application that can provide feedback on daily food intake and that relates informative stories to attractive display of fruit and vegetables.
3. Evaluative study The individual concepts of the two ranges were included in an explorative online study. The aim of this study was to determine how positive parents of young children were about the various concepts. Next to this, we wanted to get an idea on how parents think their children would evaluate the concepts. In addition, we were interested to find whether the parents think the products will influence the snack preference of their children and/or have a positive effect on their awareness of the importance of healthy eating and snacking.
3.1 Method Participants were recruited via email and were asked whether they had children in the age range of 2-‐7 years old. If they responded positively, they were directed to an online survey that was made available through Google forms. In total, 18 participants responded to the survey, (1 male, ages ranged between 28-‐42). The online survey started by giving an explanation on healthy snacks for young children giving some examples that were taken from the Dutch Centre for Nutrition. Consecutively, the participants answered a questionnaire that consisted of two parts. The first part of the questionnaire was designed to be able to classify the respondents in one of two groups to indicate the stage of change that they were in. A similar approach was suggested by Rhee et al (2014). The second part of the questionnaire was aimed at evaluation of the designed concepts. In the first part of the questionnaire, two questions were asked from the Processes of Change Questionnaire (‘I give my child a maximum of two unhealthy snacks per week.’ Answer ‘yes’ or ‘no’) and ‘I am planning to give my child less unhealthy snacks in the coming 6 months.’ Answer: ‘not likely’ or ‘somewhat likely’ or ‘very likely’)) The survey continued to ask participants to rate four questions about self-‐efficacy on a 5 point scale with endpoints ‘not at all confident’ and ‘extremely confident’: ‘How confident are you that you will give your child a healthy snack in
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each of the following situations...’ (When I feel tired; When I feel I do not have time; When my child asks for candy or salty snacks; When other children do get an unhealthy snack). Next, participants were asked to rate five statements on decisional balance on 5 point scales with end points ‘do not agree at all’ and ‘completely agree’ (‘My child would feel better if he or she would only eat healthy snacks’; ‘It would make me feel good to give my child something healthy every day’; ‘Giving my child only healthy snacks is a lot of work’; ‘My child would be physically healthier when he/she would eat healthy snacks rather than unhealthy snacks’ ‘My life is too rushed to give my child healthy snacks’.
In the second part of the questionnaire, participants evaluated the different concepts by rating 4 or 5 statements that generally asked about whether the parent and his or her child(ren) would enjoy using the concept (liking) and if they thought it would support them to eat or give healthier snacks (effect). These statements were slightly different for each of the concepts, depending on their intended use, but were all asked on five point scales with end points ‘do not agree at all’ and ‘agree completely’ (see Table 1 and 2). Additionally, participants were asked to give comments or suggestions. Each of the participants evaluated the concepts for one of the concept ranges. Eventually, the concepts in the ‘My body is a factory’ range were evaluated by 11 participants and the concepts in the ‘Healthy food made fun’ range were evaluated by 7 participants. The questionnaire ended with 9 demographic questions about the participant and his or her children.
3.2 Results The questions in the first part of the questionnaire were used to categorize participants into one of two groups: they were either categorized as being in earlier stages of change ((pre-‐) contemplation) or in middle stages of change (preparation/action). This categorization was done as follows: for every aspect of the first part of the questionnaire (self-‐efficacy, decisional balance and Processes of Change questionnaire), we determined to which group the participants would belong. A participant was assigned to the group that matched best (confirming at least 2 of the 3 questionnaire parts). Following this procedure, 3 participants that were assigned to the ‘My body as a factory concept range’ were categorized as being in earlier stages of change and 8 were categorized as being in middle stages of change. All 7 participants that were assigned to the ‘Healthy food made fun’ concept range were categorized in middle stages of change. Because of the low number of participants that was assigned to lower stages of change it will not be very insightful to compare between the groups in different stages of change. However, this analysis has informed us about the stages of change that our participants were in overall, which was mostly at least beyond contemplation and into preparation and action. Using this information as a starting point, we can evaluate the ratings of participants for the concepts that were developed for different stages of change. To do this, we calculated mean ratings of the questions in the second part of the questionnaire per concept, Table 1 shows the results of this analysis for the concept range ‘My body as a factory’.
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Table 1. Mean ratings on liking and expected effect for the different concepts in the ‘My body as a factory’ range.
Concept aimed at Statement
m (n=11)
triggering
My child will better understand the importance of healthy snacks after playing this game 4.0 My child would rather eat healthy snacks after playing this game 2.9 It would be easier for me to give healthy snacks if my child would play this game 3.5 My child would enjoy playing this game 4.0 I would like it if my child would play this game 3.6
awareness
It would be easier for me to give healthy snacks if my child would play this game 2.5 After playing this game my child will better understand what healthy snacks are 3.7 If my child would use this app it would rather eat healthy snacks 3.5 My child would enjoy playing this game 3.9 I would let my child play this game 3.7
enabling
It will not take me much time to read a story to my child during snack time 1.9 Using this product will increase my child's awareness of the importance of healthy snacks 3.6 Reading this book together will stimulate me to give healthy snacks more often 2.6 Because of these stories my child will prefer fruit and vegetables as snacks 2.7 My child would enjoy listening to these stories 3.8
motivation
If this tower is on the table my child will have less need for unhealthy snacks 3.4 Using this product my child will ask for unhealthy snacks less often 3.7 The tower will help me to only give healthy snacks to my child 3.5
It will cost me little time to make healthy snacks for my child(ren) in this way 3.6
From Table 1, it can be seen that in general, participants were quite positive about the concepts that were created; many of the scores are above the median of 3. A more detailed look at the responses also shows that although participants reported that their children would enjoy (playing with) the concepts that were created, they are less positive about the actual effects on snacking behaviour that they will have. This is especially the case for the concepts that were created for lower stages of change such as the story book and plate that was aimed at enabling. This concept scores relatively high on questions asking about if the child would enjoy it (m = 3.8) and if the concept would raise awareness of the issue (m = 3.6) but lower on questions asking about the actual effect on behaviour of parent and child (m = 2.7 and m = 2.6). The product that was aimed at motivation, the snacking tower, did receive higher scores on both liking and effect on behaviour.
Table 2 shows the mean scores for the concept range ‘Healthy food made fun’. From Table 2 the image arises that in general, the score for the concepts in the range ‘Healthy food made fun’ are somewhat lower than those for the range ‘My body is a factory’. Similar to what was found for the ‘My body as a factory’ concept range, scores for liking of the concepts are somewhat higher than scores for statements about the actual effects on behaviour. Interestingly, for this concept range, this is not only true for the concepts that were
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developed for earlier stages of change but also for the concept that was designed for the motivation stage. We will come back to these findings in the discussion.
Table 2. Mean ratings on liking and expected effect for the different concepts in the ‘Healthy food made fun’ range.
Concept aimed at Statement
m (n=7 )
triggering
With this product, my child will like to eat fruit as a treat 4.0 My child would enjoy handing out fruit treats using this product 4.1 I myself would like to hand out healthy treats using this product 3.7 It is not too much work to make healthy treats for my child in this way 3.6 After using this product, my child would more often want to eat fruit and vegetables 2.3
awareness
This way of packaging fruit motivates me to make a healthy snack for my child 2.3 I do not think it is too much work to make a healthy snack for my child in this way 3.1 The application is useful to get more tips on making fun snacks 3.4 Because of this packaging my child would prefer to eat fruit over an unhealthy snack 2.1
enabling
I would enjoy using this box to make healthy snacks 2.7 My child would like to take the fruit box to school 3.3 Because of this product, my child would enjoy eating fruit and vegetables more 2.9 The fruit box gives me a fast and easy way to make a correct portion of fruit 2.6 I would save for different rubber shapes 2.0
motivation
Because of this application my child will be motivated to eat healthy snacks 2.4 The new ideas for fruit figures that the application provides are fun 3.3 Using this application, my child would have less need for unhealthy snacks 2.4 The application helps me to determine the correct portion size for my child 2.4 The application would motivate me to give less unhealthy snacks to my child 1.4
As a final remark for this section we would like to point out that it seems that the amount of time that parents need to spend on making the snacks or are required to play a role in using the intervention limits their expected adoption.
3.3 Discussion Generally, it seems that our participants favoured the products in the ‘My body as a factory’ concept range over the ‘Healthy food made fun’ concept range. The reason for this could possibly be traced back to the difference in approach of both concepts. Whereas the concept range ‘My body as a factory’ focusses on teaching about healthy eating, the concept range ‘Healthy food made fun’ only aims at making eating heathy snacks more fun and attractive. As we have discussed, most of our participants (15 out of the total of 18) were in middle or later stages of change. People in these stages of change highly value learning about good behaviour rather than just a fun and enjoyable product. Moreover, the same 15 out of 18 respondents had a higher education diploma, this may also have had an effect on
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the results obtained here. Several studies have found that in general, people with higher levels of education are generally less prone to unhealthy behaviour (Devaux et al., 2011). Possibly, the concepts in the ‘Healthy food made fun range’ would be more attractive to a different audience that is in earlier stages of change. Another reason for the higher scores that participants gave to concepts in the ‘My body as a factory’ range could be that the concepts that were developed for later stages of change in this range were more aimed at activating and providing support (and actual physical tools) in action. We tried to do the same for the ‘healthy food made fun’ concept range but were probably less successful here, the concepts developed for this range still relied on providing information quite a bit.
Another important conclusion to draw is that although parents value healthy snacking and learning about healthy eating behaviour, they are not willing or capable of investing a considerable amount of time in that.
4. General discussion The design case presented in this paper has provided an example of how the Design for healthy behaviour Framework may aid designers in developing interventions that are targeted at multiple stages of change. From the evaluative online study we found that participants expected that some of these examples would have an influence on their (and their children’s) awareness of the importance of healthy snacking. Furthermore, they expected a few of these examples to have an effect on their actual snacking behaviour. Further studies, that include the actual use of new products and services, could be aimed at providing evidence that designing for various stages of change can result in products and services that are able to change people’s eating behaviour.
It is, however, important to note here that in our society, people constantly face an environment that persuades them towards unhealthy behaviour. Think, for example of standing in line at a cash register and being confronted with unhealthy snacks. Or, think of the many cities in which it is almost impossible to use other forms of transportation than a bike. See in this light, supporting healthier behaviour through products and services may seem like a mere drop in the ocean.
It is only fair to say that any kind of change is extremely difficult to accomplish and as of yet, we have no experimental evidence that following the proposed design framework will make it any easier. However, targeting design interventions to people’s motivational state and, thereby, addressing how ready and willing to change people really are, seems like a logical approach. Moreover, there is evidence that changing our environment through design can have positive effects on healthy behaviour. For example, Wansink and colleagues have showed how many elements in the design of our environments, including the size of our plates (Wansink & van Ittersum, 2013) and the shapes of our glasses (Wansink & van Ittersum, 2007) influence food and drink intake in both adults and children. Moreover, much in line with what Lambrick et al (2014) advocate, we would like to argue that especially in
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the health challenging environment that we face today, all possible efforts to support the vulnerable but also promising group that children are, are desperately needed.
5. References Devaux, M., Sassi, F., Church, J., Cecchini, M., & Borgonovi, F. (2011). Exploring the relationship
between education and obesity. OECD Journal: Economic Studies, 5(1), pp. 1-‐40. Lambrick, D. M., Stoner, L., Faulkner, J., & Hamlin, M. J. (2014). Preventive Medicine Needs to Begin
with Our Children. International Journal of Preventive Medicine, 5(1), pp. 129-‐131. Ludden, G.D.S. & Hekkert, P. (2014) Design for healthy behavior. Design interventions and stages of
change. Proceedings of the Colors of Care: The 9th International Conference on Design & Emotion. Bogotá, Colombia, October 6-‐10, pp. 482-‐488.
Ludden, G.D.S. & Offringa, M. (2015) Triggers in the environment. Increasing reach of Behavior Change Support Systems by connecting to the offline world. Proceedings of the Third International Workshop on Behaviour Change Support Systems co-‐located with the 10th International Conference on Persuasive Technology (PERSUASIVE 2015), Chicago, IL, USA, June 4-‐5, pp. 7-‐16.
McCrory, M. A., Fuss, P. J., McCallum, J. E., Yao, M., Vinken, A. G., Hays, N. P., & Roberts, S. B. (1999). Dietary variety within food groups: association with energy intake and body fatness in men and women. American Journal of Clinical Nutrition, 69(3), pp. 440-‐447.
Prochaska, J. O., DiClemente, C. C., & Norcross, J. C. (1992). In Search of the Structure of Change. In Y. Klar, J. D. Fisher, J. M. Chinsky & A. Nadler (Eds.), Self Change -‐ Social Psychological and Clinical Perspectives (pp. 87-‐114 ). New York: Springer -‐ Verlag.
Prochaska, J. O., & Velicer, W. F. (1997). The Transtheoretical Model of Health Behavior Change. American Journal of Health Promotion, 12(1), pp. 38-‐48.
Rhee, K., McEachern, R., & Jelalian, E. (2014). Parent readiness to change differs for overweight child dietary and physical activity behaviors. Journal of the Academy of Nutrition and Dietetics, 114(10), pp. 1601-‐1610.
Schonfeld-‐Warden, N., & Warden, C. H. (1997). Pediatric obesity. An overview of etiology and treatment. Pediatr Clin North Am, 44, pp. 339-‐361.
Signorielli, N., & Staples, J. (1997). Television and children's conceptions of nutrition. Health Communications, 9(289).
Sothern, M. S. (2004). Obesity prevetion in children: physical activity and nutrition. Nutrition, 20, pp. 704-‐708.
Wansink , B., & van Ittersum, K. (2007). Do children really prefer large portions? Visual illusion bias their estimates and intake. Journal of the American Dietetic Association, 107(7), pp. 1107-‐1110.
Wansink, B., & van Ittersum, K. (2013). Portion size me: plate-‐size induced consumption norms and win-‐win solutions for reducing food intake and waste. J Exp Psychol Appl., 19(4), pp. 320-‐332.
About the Authors:
Geke Ludden is assistant professor in the Interaction Design group at the University of Twente. Her work focuses on the (theoretically informed) development and evaluation of products and services that
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support healthy behaviour or that otherwise contribute to people’s wellbeing.
Laura de Ruijter received her masters’ degree in industrial design engineering in 2016. She is interested in developing products and services that influence people’s behavior. Her latest work investigated the impact of consumer behaviour on the success of new developments in the circular economy.
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