The influence of health motivation and the roles of
consumer values and temporal distance on healthy
food decision-making
Renée van Dijk
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The influence of health motivation and the roles of
consumer values and temporal distance on healthy
food decision-making
by
Renée van Dijk
University of Groningen
Faculty of Economic and Business Msc Marketing Management Master Thesis June 14, 2016 Zoutstraat 29 9712 TB Groningen 0031 6 54 64 40 18 r.j.van.dijk.1@student.rug.nl Student number: S2185512
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ABSTRACT
Previous research shows inconclusive results with regard to the role of autonomous and controlled health motivation on intentions to choose and actually choosing healthy food products. It is expected that several value orientations play a different role on this relationship by strengthening or weakening the effect. Also letting consumers choose on different moments in time is expected to affect this relationship.
The regression analyses of two researches, a field study and lab experiment, revealed that controlled health motivation did not show a significant effect, while the autonomous health motivation positively influenced the choice of healthy food products. The consumer value orientations did not significantly strengthen or weaken this relationship. The difference in time reached significance on the relationship between controlled health motivation and the choice of healthy food products.
Keywords: healthy food decision-making, health motivation, egoistic value orientation, biospheric value orientation, altruistic value orientation, hedonic value orientation, temporal distance
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MANAGEMENT SUMMARY
Obesity problems are highly increasing worldwide (World Health Organization, 2015) and unhealthy food intake is one of its main causes (Bui et al., 2015; Mullan et al., 2014). People’s food intake is influenced by many factors (Verain et al., 2015), of which health concerns are increasingly important (Ronteltap et al., 2011; McSpadden et al., 2016). Nevertheless the relationship between health concerns and actually choosing healthy food products is inconclusive (Burton et al., 2015; Verain et al., 2015), which gives an opportunity for further investigation. In this research two factors are investigated that are expected to strengthen or weaken this relationship: consumer value orientations and a time difference.
With regard to the consumer value orientations, previous literature shows that there are four value orientations influencing consumers’ health-related behaviour and food motivations: egoistic, biospheric, altruistic and hedonic value orientations (Rocas & Sagiv, 2010; de Groot & Steg, 2010; Brunso et al., 2002; Ryan & Deci, 2002; de Groot & Steg, 2010). Secondly, literature also shows that as the time between choosing and receiving increases, consumers order a higher percentage of ‘should’ items (e.g., healthy food products) and a lower percentage of ‘want’ items (e.g., unhealthy food products) (Milfont & Gouveia, 2006; Milkman et al. 2010).
For this study, there was an opportunity to work with two databases of the University of Groningen, consisting of data with regard to healthy food decision-making behavior. The findings show that autonomous health motivation does influence healthy food decision-making, where controlled health motivation does not affect this relationship. The consumer value orientations did not seem to strengthen or weaken this relationship. This could possibly be explained by that egoistic individuals compute other actions to improve their health and more value price than healthiness (Magnusson et al.,2003; Verain et al., 2015), biospheric and altruistic individuals choose other beneficial food products (e.g. organic products) (Aygen, 2012; Magnusson et al. 2013; van Doorn & Verhoef, 2015; Kareklas et al. 2014) and hedonic individuals simply choose whatever they want to eat (Jun et al., 2015). A difference in time only reached significance on the relationship between controlled health motivation and the choice of healthy food products. The lack of effect could be explained by that autonomous motivated individuals do not take future consequences into account and rely on short-term benefits of unhealthy eating (Stratman et al., 1994; Mullan et al., 2014).
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PREFACE
Firstly, I would like to thank my supervisors, dr. Koert van Ittersum and dr. J. van Doorn, for providing me valuable feedback and motivating me to get the best out of this research. They quickly responded to questions and let me critically look at my work. Secondly, my parents deserve a special word. They supported me in the decisions I made during my studies and will always motivate me to get the best out of life.
As my time in Groningen is coming to an end, I can look back with a great smile. I have learned a lot, got to know many new and interesting people, personally developed myself and enjoyed my student life. This Master’s Thesis is the end of a great period of my life, but also the beginning of a new, exiting period. I look forward to bring all my learned skills and knowledge into practice.
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1. INTRODUCTION
Obesity is an increasingly important worldwide problem, as it is a causative factor for many diseases, such as diabetes, coronary heart diseases and some types of cancer (World Health Organization, 2015). One of its main causes is people’s unhealthy food intake (Bui et al., 2015; Mullan et al., 2014). Given the importance of fruit and vegetable consumption and limiting saturated fat intake in preventing obesity (Mullan et al., 2014), it is important to understand consumers’ motivation to purchase food products.
Consumers’ interest in purchasing food products is influenced by many factors (Verain et al., 2015). Most influencing factors are consumers’ level of personal disposable income, the presence of children, a predominant age-range, the taste and the appearance of nutrition labels (Verain et al., 2015; Titterington & Cochrane, 1995; Zhu et al., 2016). Moreover, health concerns are an important reason. An increasing amount of consumers desire healthier food (van Doorn & Verhoef, 2011; Titterington & Cochrane, 1995) and consumer research has shown that is among the most important motives for food choice (Ronteltap et al., 2011; McSpadden et al., 2016). Therefore, many food companies are offering more healthy products and healthiness became a critical factor influencing the success of food-related businesses (Bui et al., 2015).
Thus, there is an increasing trend towards consumers’ intentions to engage in health behaviors. Research regarding consumers’ intentions to engage in health behaviors and their actual behavior is widely discussed and the majority shows a positive relationship (Kraus & Piqueras-Fiszman, 2016). However, these results are not always valid (Burton et al., 2015; Verain et al., 2015). In practice, when consumers select the food that they will consume, they often do not make this choice due to perceived barriers (Aschmann- Witzel & Niebuhr Agaard, 2014). Therefore, the relationship between consumers’ health intentions and their actual behavior gives an opportunity for further investigation of the antecedents that influence this relationship.
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2015; Kotler, 2002) and that consumer values strengthen their motivation to show a certain behavior (Brunso et al., 2002; de Groot & Steg, 2010). Values are defined as stable constructs that do not change easily, and therefore can serve as predictors of behaviour over extended periods of time (Krystalis et al., 2012). Schwartz (1992) identified ten basic values, which serve as guiding principles in the life of a person or group. Consumers differ in terms of importance of these values (Verain et al., 2015; Bardi & Schwartz, 2003) and it is highly important to take this consumer heterogeneity into account in order to better understand and influence consumer food choices (Dagevos, 2005). In the literature, the influence of specific consumer value orientations on the relationship between health interest and behaviour remains unclear.
Besides that, the consideration of future consequences plays an important role. Research has shown that the explanation for what influences consumer interest and when the consumer considers to purchase the food product, differs when individuals have to make a choice now versus later (Trope et al., 2007). Also research of Milkman et al. (2010) has shown that customers spend less, order a higher percentage of ‘should’ items (e.g., healthy food products) and order a lower percentage of ‘want’ items (e.g., unhealthy food products) the further in advance of delivery they place a grocery order.
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(Milkman et al., 2010). Therefore, the following research questions will be the point of focus of this paper:
1. What is the influence of autonomous and controlled health motivation on the choice of healthy food products?
2. What is the effect of consumer value orientations on the relationship between autonomous and controlled health motivation and choice of healthy food products? 3. What is the effect of making a decision now or in the distant future on the relationship
between autonomous and controlled health motivation and the choice of healthy food products?
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2. THEORETICAL FRAMEWORK
In this chapter an overview of the available literature will be provided. Currently, obesity is a worldwide problem (World Health Organization, 2015). Individuals are intrinsically or extrinsically encouraged to consume healthy food, as these food products provide nutrients to stay healthy and have a positive effect on well-being (Ronteltap et al., 2011; McSpadden et al., 2016; Netherlands Nutrition Centre, 2016; Niermann et al., 2015). Firstly, the definition and the importance of health motivation on decision-making behavior will be given. Then the different consumer values and their relevance towards consumers’ food choice will be discussed. Next the influence of time on the relationship between health motivation and the choice of healthy food products will be a focus point. Several hypotheses will be formed, which will be examined in the following chapters.
2.1 Research on the relationship between health motivation and the choice of healthy food products
Consumers interpret healthful food in various ways. It can be discussed either in “specific terms, proportions of proteins, grains, vegetables and carbohydrates that should be consumed, or by using general terms such as a ‘balanced’ diet or eating ‘proper meals’ and variety” (Ronteltap et al., 2011, p. 334). Generally, health foods are defined as low calorie foods, with a limited amount of fats, salt and simple sugars (Jun et al., 2015; Hensen et al., 2010). Organizations promoting a healthy diet suggest decreasing energy-dense, high calorie foods and drink, and increasing consumption of fruits, vegetables and whole grains (Brouwer & Mosack, 2015).
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The antecedent factors and processes that underpin people’s motivation to engage in health-related behavior are widely discussed in different theories. The most important theories are the theory of planned behavior, the self-determination theory and the health action process approach (Girilli et al., 2015). In this study the self-determination theory will be discussed. Here, Deci & Ryan (2002) state that there are two types of motivation, autonomous and controlled, to predict long-term maintenance of motivated behavior change. Firstly, “autonomous behavior are ones for which the regulation is experienced as chosen and as emanating from one’s self” (Williams et al., 1996). Here, individuals experience a sense of personal choice and autonomy in the implementation of a certain behavior (Girilli et al., 2015). Research has shown that autonomous motivation positively relates with eating healthy foods and is likely to facilitate healthier food habits (McSpadden et al., 2016; Mullan et al., 2014).
Secondly, controlled behaviors are one for which the regulation is experienced as pressured or coerced by some interpersonal force, perceived or real (Williams et al., 1996; Girilli et al., 2015). More controlled forms of motivation include engaging in a behavior to achieve social approval, to earn rewards or to avoid self-inflicted feelings of guilt (McSpadden, 2016). Besides that, there is evidence that controlled motivation is associated with subjective norms (Girilli et al., 2015). Subjective norms reflect social pressure to engage in behavior, as “individuals perception of whether significant others want them to perform the behavior will predict their intention to undertake the behavior” (Chan et al., 2016, p. 17). According to the research of Chan et al. (2016) the subjective norm supporting healthy eating positively relates to people’s intention to engage in healthy eating. McEachen et al. (2010) also found that healthy food consumption decisions are more likely to be influenced by consumers’ perceived social pressure and judgments.
H1a. Autonomous health motivation has a positive effect on the choice of healthy food products.
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2.2 Research on the influence of consumer values on the relationship between both health motivations and the choice of healthy food products
Previously, the relationship between autonomous and controlled health motivation and the choice of healthy food products is discussed. Now it will be argued to what extent this relationship is strengthened or weakened by consumer values.
2.2.1. Consumer values
Values are widely defined as concepts or beliefs about desirable transsituational goals, varying in importance, that serve as guiding principles in the life of a person or other social entity (Schwartz, 1992). Briefly, values point out desirable goals that motivate action. There are ten basic values: self-direction, stimulation, hedonism, achievement, power, security, conformity, tradition, benevolence and universalism. Schwartz value theory is extensively used to examine the relationship between values and consumer behaviour. This theory shows that there are two dimensions. The vertical dimension of ‘self-enhancement (i.e., egoistic) – self-transcendence (i.e., altruistic or biospheric)’ contrasts the values of power and achievement with the values of universalism and benevolence. The horizontal dimension of ‘openness to change – conservation’ contrasts the values of self-direction and stimulation with the values of security, conformity and tradition (Krystallis et al. 2012; Groot & Steg, 2007). In most research the self-transcendence items can be divided into an altruistic value orientation and a biospheric value orientation, where the items of self-enhancement are clustered into an egoistic orientation (Dietz et al., 2002).
Bardi & Schwartz (2003) discovered that individuals differently rank the importance of certain values, which explains the difference in their attitude or behaviour. A particular value can be important to one person but unimportant to another (Bardi & Schwartz, 2003). Because of this difference, it is possible to segment consumers based on their values (Verain et al., 2012). Segmentation based on values is not only useful because of their close relationship with consumers’ motives and behaviour (Krystallis et al., 2012), but also because the total number of values is relatively small. Therefore it is an economically valuable tool for describing and explaining the difference between consumers’ choices (Krystallis et al., 2012; Groot & Steg, 2007).
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importance of values influencing consumer behaviour. Dietz et al. (2002) affirm that values can be seen as points of reference in decision-making like product choice. Also Brunso et al. (2004) state that values are criteria that people use as guidelines for evaluating stimuli. According to Groot & Steg (2007) values are general in nature and therefore may affect various beliefs and behaviours simultaneously. Also Kotler (2002) states that the stages of a decision-making process are internally influenced by values, which lead to purchase or no purchase. Importantly, research shows that personal values (e.g., hedonism, self-direction, excitement) are important guiding forces in the food context and highly influence consumption of low-involvement products (Hauser et al., 2013). Moreover, a strong empirical support has been found for the link between consumer values and food products (Krystallis et al. 2012) as both influence the behaviour towards differentiated products.
Importantly, not only the effect of consumer values on behaviour is shown, as Brunso et al. (2002) also show that human values are assumed to strengthen the motivation for human behaviour in situations where choices are involved. Also de Groot & Steg (2010) state that individuals do not act out of their motivation only and the role of values is remarkably underestimated. Ryan and Deci (2002) suggest that stronger types of motivations lead to an integration of specific consumer values, goals and needs as part of the self. Therefore, this research assesses the moderating effect of consumer value orientations on the relationship between autonomous and controlled health motivation and the choice of healthy food products. In the literature, four consumer values influence health-related behavior: egoistic, biospheric, altruistic and hedonic values (Rocas & Sagiv, 2010; de Groot & Steg, 2010). It is important to determine if these consumer value orientations strengthen or weaken the relationship.
2.2.2. Egoistic value orientation
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and taste, than healthiness (Verain et al., 2015). The motivation-ability-behavior framework shows that highly involved consumers are more likely to actively engage towards the subject and act in a certain behavior. In general, foods are low involvement products. However, research shows that “consumers’ increasing concerns with food in terms of health aspects of eating render studies of involvement, and antecedents to involvement, in food products important” (Thomsen & Hansen, 2015, p.113). Its own interest influences the decision-making process.
H2a. The effect of autonomous health motivation on choosing healthy food products is stronger when an individual’s egoistic values are higher.
The controlled motivation argues that individuals feel pressured to choose healthy food products. Here individuals should be motivated to eat a healthy diet for others, e.g. to be more attractive for them (Girilli et al., 2015). As an individual with egoistic values relies on its own independence (Krystallis et al., 2012), social pressure of by an interpersonal force does not apply (Williams et al., 1996; Chan et al., 2016). Thus, research shows that the egoistic value orientation is negatively related to stronger extrinsic types of motivation (de Groot & Steg, 2010), and thus it is predicted that egoistic values do not influence the relationship between controlled health motivation and the choice of healthy food products.
H2b. The effect of controlled health motivation on choosing healthy food products is not influenced by an individual’s egoistic values.
2.2.3. Biospheric value orientation
Biospheric can be defined as “the value orientation that reflects concern with nonhuman species or the biosphere” (van Doorn & Verhoef, 2015, p. 439). Individuals with these values prefer eating ‘green’ for a better environment (Magnusson et al., 2003), as they consider environmental benefits and animal welfare important (van Doorn & Verhoef, 2015).
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“consumers buy organic products for health reasons” as “there is a higher health consciousness among organic consumers” (van Doorn & Verhoef, 2011, p. 176). This could mean that individuals’ biospheric values could cause a greater effect, due to a relationship between organic food products and healthiness. Moreover, research shows that biospheric values explain a significant amount of additional variance next to motivational types (de Groot & Steg, 2010). Thus, a positive effect is hypothesized, as organic food products seem interesting for these biospheric individuals for two reasons: organic products are perceived healthier for the self, and secondly because these products help the environment (Kareklas et al., 2014; Magnusson et al., 2003).
H3a. The effect of autonomous health motivation on choosing healthy food products is stronger when an individual’s biospheric values are higher.
Then, it is argued whether this effect also takes place when the motivation is controlled. This would mean that individuals like to share with the society, that they purchase healthy food products because they value the environment. As this will be difficult to notice by others, it is argued that there will not be an effect on the relationship between controlled health motivation and healthy decision-making.
H3b. The effect of controlled health motivation on choosing healthy food products is not influenced by an individual’s biospheric values.
2.2.4. Altruistic value orientation
Altruism is commonly defined as when we act to promote someone else’s welfare, even at risk or cost to ourselves (van Doorn & Verhoef, 2015). Thus, the actions that express these values promote the welfare of others (Bardi & Schwartz, 2003) and these values can be seen as the opposite of egoistic values (Krystallis et al., 2012).
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their own children or family, this can be a reason for choosing healthy food products (Niermann et al., 2015; Makantouni, 2002). “Generally, people will perform a certain behavior if they are motivated to comply to their important referents and perceived social pressure from them to perform the behavior” (Chan et al., 2016, p. 18). Thus, when an individual is intrinsically health- motivated, the extra benefit of doing well for other people will strengthen its decision-making process, as research shows that altruistic value orientations were positively related to an intrinsic motivation (de Groot & Steg, 2010). On the other hand, when an individual feels pressured by an interpersonal force (Williams et al., 1996), its altruistic values will even more force to conform and influence its decision-making process (Bardi & Schwartz, 2003).
H4a. The effect of autonomous health motivation on choosing healthy food products is stronger when an individual’s altruistic values are higher.
H4b. The effect of controlled health motivation on choosing healthy food products is stronger when an individual’s altruistic values are higher.
2.2.5. Hedonic value orientation
Hedonism can be defined as “the pleasure and sensuous gratification for oneself” (Bardi & Schwartz, 2003, p. 1208). ‘He/she really wants to enjoy life. Having a good time is important to him/her’ states a consumer to whom hedonic values are important. As with both types of health motivations, motivation is driven by one-self or interpersonal forces (Deci & Ryan, 2002). Individuals with hedonic values sometimes choose whatever they want to eat without rational consideration and food selections are therefore not only determined through deliberative reasoning processes (Jun et al., 2015). Moreover, these individuals will barely overthink their decisions (Krystallis et al., 2012) and prefer eating enjoyment, which overrides their intended healthy behavior and their ability to say no (Naugthon et al., 2015). Thus, it is highly argued that individuals with hedonic values weaken the relationship between both health motivations and healthy food decision-making.
H5a. The effect of autonomous health motivation on choosing healthy food products is weaker when an individual’s hedonic values are higher.
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In sum, consumers differently rank the importance of values (Bardi & Schwartz, 2003). These value orientations lead to different decision-making behavior (Krystalis et al. 2012; Dietz et al., 2002; Brunso et al., 2004; Groot & Steg, 2007; Hur et al., 2015; Kotler, 2002), and thus differently moderate the relationship between autonomous and controlled health motivation and the choice of healthy food products, as summarized in the table below.
TABLE 1: Overview of effects of consumer value orientations
Consumer value orientations Type of health motivation Autonomous Controlled Egoistic value orientation H2a (+) H2b Biospheric value orientation H3a (+) H3b Altruistic value orientation H4a (+) H4b (+) Hedonic value orientation H5a (-) H5b (-)
2.3. Research on the influence of a time difference on the relationship between both health motivations and the choice of healthy food products
Previously, the relationship between both health motivations and the choice of healthy food products is discussed, and the role of consumer value orientations on this relationship. Now it will be discussed whether this relationship will be influenced by if people have to make the decision now or in the distant future.
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Distancing the target on the time dimension increases the extent to which individuals mentally represent objects and events in a more abstract (vs. more concrete) manner. This temporal distance is commonly defined as the effects of construing a future object, event, or behavior as being in the distant versus proximal future (Liberman et al., 2001). This construal level influences a large amount of cognitive processes, and the theory is successively applied to consumer choice (Ronteltap et al., 2011). For example, it is stated that when the time between purchasing decision and receiving the purchase is exogenously varied, this delay can alter people’s own selections (Milkman et al., 2010). Milkman et al. (2010) found that as the time between choosing and receiving increases, consumers order a higher percentage of ‘should’ items (e.g., healthy food products) and a lower percentage of ‘want’ items (e.g., unhealthy food products).
This is due to several reasons. Firstly, when individuals have to choose immediately, they behave more impulsively. Thus, they spend more and choose more items they hedonically want to select over items they cognitively believe they should select (Milkman et al., 2010). According to Dassen et al. (2015) consuming unhealthy foods has immediate pleasurable results, whereas healthy eating offers benefits in the long run. Besides that, research has shown that people tend to focus on the positives when thinking about events in the distant future, but focus on the negatives when thinking about events in the proximal future (Spassova & Lee, 2013).
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H6a. The relationship between autonomous health motivation and choosing healthy food products is stronger when an individual has to make a decision in the distant future. H6b. The relationship between controlled health motivation and choosing healthy food
products is stronger when an individual has to make a decision in the distant future.
2.4 Conceptual model
The aforementioned hypotheses are visually presented in the conceptual model below. The model depicts two types of health motivation, autonomous and controlled, as main antecedents of healthy food decision-making. The egoistic, biospheric, altruistic and hedonic value orientations are assumed to play a positive or negative moderating role on this relationship, as there is a gap between consumers motives and their actual behavior. Also the temporal distance is assumed to have a moderating role on this relationship.
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3. RESEARCH DESIGN
The following section describes the method of data collection. To be able to test the hypotheses, two existing databases designed by researchers of the University of Groningen are used. First the characteristics of the datasets will be described, followed by the measurements of the variables and the modelling approach.
3.1 Design
3.1.1 Study 1: field study
The dataset of the field study at the University of Groningen is used. In this experiment 216 students participated, 113 males (52.3%) and 103 females (47.7%). The average age of the participants is 21 years old (SD =2.628). During lectures participants were invited to join a free meal two hours or 7 days from now and choose between several lunch options. Then, participants were asked to fill in a questionnaire with questions concerning demographics, satisfaction with the meal, hungriness, values, health motivation, dieting, price sensitiveness, peer pressure and food waste. Participants received and consumed their lunch option. Only the data of their decision-making behaviour, values and health motivation is used.
3.1.2 Study 2: lab experiment
Also the dataset of a lab experiment at the University of Groningen is used. In this study 221 students participated, wherefrom the data of 206 participants is used. Of this, 99 males (48.1%) and 107 females (51.9%) participated. The average age of the participants is 20 years old (SD =1.779). Participants were asked to participate in the lab experiment and fill in a questionnaire. Similar questions as in the field experiment were asked and used. Contradictory to the field experiment, the chosen lunch option was not received and consumed.
3.2 Measures
3.2.1. Dependent variable: choice of healthy food products
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𝑆𝑂𝑂!!"#$!,! =𝑜𝑝𝑡𝑖𝑜𝑛𝑠!!"#$!,! 𝑜𝑝𝑡𝑖𝑜𝑛𝑠!"!#$,!
Where 𝑆𝑂𝑂!!"#$!,! is the share of healthy lunch options in period t; 𝑜𝑝𝑡𝑖𝑜𝑛𝑠!!"#$!,! refers to the number of healthy lunch options in period t; and 𝑜𝑝𝑡𝑖𝑜𝑛𝑠!"!#$,! to the total number of chosen
lunch options in period t. In total there were 6 lunch options, shown in table 2. These lunch options are divided into two factors: unhealthy and a healthy lunch options.
TABLE 2: Healthiness of lunch options
Lunch option field study Lunch option lab experiment Healthiness of food product
Muesli roll with cheese Muesli roll with cheese
ü
Multigrain roll with chicken fillet and cucumber Multigrain roll with chicken fillet and cucumberü
Fruit Multigrain roll with cheese and cucumberü
Cheese roll Slice of pizza margarita û Croquette in a bun Croquette in a bun û Sausage roll Sausage roll ûThe descriptive statistics of the items measuring the dependent variable are shown in table 3.
TABLE 3: Descriptive statistics lunch options
Lunch option N Frequency Mean SD Min Max
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The correlation matrices are added in Appendix A (table 4 and 5). Both studies show a moderate correlation between autonomous health motivation and the choice of healthy food product, where a low moderation is shown between controlled health motivation, the consumer value orientations, the temporal distance and the choice of healthy food products. The consumer value orientations and temporal distance correlated low or moderately with each other. Only the biospheric and the hedonic value orientation show a high correlation in the field study (.539) and lab experiment (.637).
3.2.2. Independent variables: autonomous and controlled health motivation
The measurements for the autonomous and controlled health motivation are derived from Ryan & Deci (2002) and measured by 15 items: 6 assess autonomous motivation, 6 assess controlled motivation and 3 assess amotivation on a 7-point Likert scale. The endpoints are labelled as ‘not at all true’ and ‘very true’. Only the data of the autonomous and controlled motivation is used. The detailed measures can be found in Appendix B (table 6).
In the field study, a correlation analysis showed that the 6 items measuring autonomous health motivation significantly correlated (p =.00), and after combining showed a Cronbach’s Alpha of .850. Also the 6 items measuring controlled motivation showed a significant correlation (p=.00) and after combining these items showed a Cronbach’s Alpha of .837. Thus, it is shown that the items for both health motivations can be recoded into two sum variables.
In the lab experiment, similar results are shown. The 6 items measuring autonomous health motivation significantly correlate (p =.00) and a Cronbach’s Alpha of .856 is shown, and the 6 items measuring controlled health motivation showed a significance (p=.00) and a Cronbach’s Alpha of .837.
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3.2.3. Moderator: consumer value orientations
The measurements for the four value orientations (egoistic, biospheric, altruistic, hedonic) are derived from Steg et al. (2005) and measured on a nine-point Likert scale. The endpoints are labelled as ‘not at all important’ and ‘of supreme importance’. The detailed measures can be found in Appendix B (table 7).
In the field study, the correlation analysis shows inconclusive results. Items of different value orientations show high correlations with each other and just some items of a value orientation meet a significant correlation. The combination of the items that measure the egoistic, biospheric, altruistic or hedonic value orientations also show a low Cronbach’s Alpha: egoistic value orientation α= .481, biospheric value orientation α= .619, altruistic value orientation α= .345 and hedonic value orientation α= .291. After deleting an item, the altruistic value orientation reaches α = 0.364 and the hedonic value orientation α= .374. Therefore a factor analysis using principal components estimation is performed (KMO = .777) to delete items that score high on more than one value orientation. Nevertheless, this analysis shows factors with high loading items on different value orientations. Also deleting one of the value orientations gives these inconclusive results. Concluding, the effect of the egoistic, altruistic and hedonic value orientations cannot be tested on the relationship between both health motivations and the healthy food decision-making behaviour.
In the lab experiment, the correlation analysis shows better results and items of a value orientation meet significance. The combination of the items that measure the value orientations show higher Cronbach’s Alpha’s: egoistic value orientation α= .635, biospheric value orientation α = .726, altruistic value orientation α = .566 and hedonic value orientation
α= .528. After deleting an item, the altruistic value orientation reaches α = .605. The value orientations are standardized to increase interpretability of the interactions, after which the interaction terms are created by multiplying the standardized value orientation with the standardized autonomous and controlled health motivation variable.
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TABLE 8: Measures and their reliability
Scale Source Number of
items Range Cronbach’s alpha Field experiment Autonomous health motivation Ryan & Deci (2002) 6 1 – 7 .850 Controlled health motivation 6 1 – 7 .837 Egoistic value orientation Steg et al. (2005) 5 1 – 9 .481 Biospheric value orientation 4 1 – 9 .617 Altruistic value orientation 4 1 – 9 .364 Hedonic value orientation 3 1 – 9 .274 Lab experiment Autonomous health motivation Ryan & Deci (2002) 6 1 – 7 .856 Controlled health motivation 6 1 – 7 .837 Egoistic value orientation Steg et al. (2005) 5 1 – 5 .635 Biospheric value orientation 4 1 – 9 .726 Altruistic value orientation 4 1 – 9 .605 Hedonic value orientation 3 1 – 9 .528
3.2.4. Moderator: temporal distance
The temporal distance is measured by randomly assignment of participants in two conditions: in the field study 112 participants (51.85%) had to make a decision for their lunch in two hours, 104 participants (48.15%) had to make a similar decision, but then for a week later. In the lab experiment, also 104 participants (50.49%) had to make a decision for in two hours, where 102 participants (49.51%) had to choose for a week later. Participants that had to make their decision immediately are coded as 0, where participants that had to make a choice within a week are coded as 1.
The descriptive statistics of the independent variable and moderators are shown in table 9.
TABLE 9: Descriptive statistics
Variable N Mean SD Min Max
25 Hedonic value orientation 216 6.708 .9261 4 9 Temporal distance 216 .520 .5010 0 1 Lab experiment Autonomous health motivation 206 4.608 1.0396 1.7 6.8 Controlled health motivation 206 2.604 1.0747 1 6 Egoistic value orientation 206 5.745 .9403 2.5 8.3 Biospheric value orientation 206 7.343 .8044 5 9 Altruistic value orientation 206 6.914 .7238 4.5 8.3 Hedonic value orientation 206 6.413 1.0322 3 9 Temporal distance 206 .500 .5010 0 1 3.3 Modelling approach
The hypotheses depicted in Figure 1 are tested in a linear regression model using SPSS. For both studies four assumptions are checked: normality, linearity, homoscedasticity and multicollinearity. In both studies, all variables are checked and normally distributed. The scatterplots show that there is no reason to assume that linearity is not satisfied in the dataset between independent variables and share of healthy lunch options chosen. Also, a scatterplot of the residuals against the predicted values shows that there is no pattern. Besides that, no high multicollinearity is shown.
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4. RESULTS
In the following chapter, the results are presented. In order to test the hypotheses, one regression analysis in the field study is executed, where two regression analyses in the lab experiment are performed. The lab experiment shows two regression models: one including the consumer value orientations and one excluding the consumer value orientations. This is done for the comparability of both studies. Both will first show the main effects, followed by the moderating effects of the value orientations and the temporal distance.
4.1 Regression analyses in both studies
4.1.1 Main effects on choice of healthy food products
In the field study, the regression analysis was significant: R²=.144, F(5, 209), p =.00, and no high multicollinearity is shown among the variables (VIF<2.695). Also in the lab experiment, the regression analysis with the consumer value orientations shows significant results: R²=.113, F(5,200), p =.00. There is no high multicollinearity among the variables (VIF<2.695).
In both studies, the results show as expected that there is a positive relationship between autonomous health motivation and the choice of healthy food products (β =.047, p =.009 and β =.156, p =.000). Nevertheless, it is found that the relationship between controlled health
motivation and the choice of healthy food products did not reach significance(β =.038, p=.166
and β =-.028, p = .477). As a consequence, H1a is supported, but H1b is not conformed. An
additional analysis is performed to test whether a time difference directly influenced the choice of healthy food product. Here, inconclusive results are shown. In the field study the effect did reach significance (β =.100, p =.004), where in the lab experiment the effect is
highly insignificant (β =-.009 , p =.852). An overview of the results with regard to the main
effects is shown in table 10.
TABLE 10: Main effects on healthy food decision-making behaviour
Unstandardized Coefficients Standardized Coefficients
Variable β Std.Err. β t p
Field study
Autonomous health motivation (H1a) .047 .028 .176 1.679 .009
27 Temporal distance .100 .034 .186 2.903 .004 Lab experiment Autonomous health motivation (H1a) .156 .038 .438 4.065 .000 Controlled health motivation (H1b) -.028 .039 -.078 -.713 .477 Temporal distance -.009 .048 -.013 -.187 .852
4.1.2 Moderating effects of temporal distance
Next to the main effects, also the moderating effect of the temporal distance is assessed on the relationship between autonomous and controlled health motivation and the choice of healthy food products. The outcomes of both studies show that temporal distance does not have a significant effect on the relationship between autonomous health motivation and choice of healthy food products (β =.062, p=.100 and β =-.096, p=.077). In the field study the
relationship between controlled health motivation and healthy food decision-making did reach significance (β =-.097, p =.011). Nevertheless, in the lab experiment, temporal distance does
not affect the relationship (β =.070, p =.189). Therefore H6a cannot be confirmed, where
H6b can only partly be supported. An overview of the outcomes regarding the moderating effect is shown in table 11.
TABLE 11: Moderating effect of temporal distance on the relationship between autonomous and controlled health motivation and healthy food decision-making
behaviour
Unstandardized
Coefficients
Variable β Std.Err. p 95% Conf. Interval
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4.2 Regression analysis in lab experiment
4.2.1 Main effects on choice of healthy food products
In order to analyse whether the consumer value orientations influence the regression, a second regression is performed for the lab experiment. The regression analysis was significant: R²=.157, F (17,188), p =.010, and again no high multicollinearity among the variables is shown (VIF<3.027).
The main effects of autonomous and controlled health motivation do not show different results compared to the previous analyses in both studies. Likewise, autonomous health motivation positively affects the choice of healthy food products, where controlled health motivation does not reach significance (β =.166, p =.000 and β =-.023, p =.578). Thus, similar
to previous results H1a is supported, but H1b cannot be confirmed.
Additionally, it is researched whether the consumer value orientations and a time difference directly influence the choice of healthy food products. The egoistic value orientation (β =.038,
p =.189), biospheric value orientation (β =.013, p =.675), and hedonic value orientation
(β =-.012, p =.711) show insignificant results. The altruistic value orientation does show a
positive significance on the choice of healthy food products (β =-.073, p =.011). Besides that,
the time difference shows a highly insignificant direct effect on the choice of healthy food products (β=-.006, p= .908). An overview of the outcomes with regard to the main effects is
provided in table 12.
TABLE 12: Main effects on healthy food decision-making behaviour
Unstandardized Coefficients Standardized Coefficients
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4.2.2 Moderating effects of consumer value orientations and temporal distance
Next to the main effects, also the moderating effects of the value orientations and the temporal distance are assessed. An overview of the outcomes is shown in table 13. Firstly, it is researched whether consumer value orientations influence the relationship between both health motivations and the choice of healthy food products. Clearly the lab experiment shows, that the value orientations do not significantly affect this relationship. The results show that none of the value orientations come close to significance: egoistic value orientation (β =-.041,
p =.274 and β =-.002, p =.965), biospheric value orientation (β =-.003, p =.934 and (β =.026,
p =.438), altruistic value orientation (β =.018, p =.557 and β =-.019, p =.549) and hedonic
value orientation (β =.044, p =.241 and β =-.010, p =.767). Therefore, it can be concluded that
all are highly insignificant, and thus that the hypotheses H2a, H3a, H4a, H4b, H5a and H5b cannot be confirmed, where H2b and H3b are supported.
Moreover, this research examined the effect of a temporal distance on the relationship between both health motivations and the healthy food decision-making behaviour. The time difference reaches significance on the relationship between autonomous health motivation and the choice of healthy food products (β =-.114, p =.046). The difference in time insignificantly
effects the relationship for controlled health motivation (β =.077 and p=.184). Therefore H6a
can be confirmed, where H6b cannot be supported.
TABLE 13: Moderating effects of consumer value orientations and temporal distance on the relationship between both health motivations and healthy food decision-making
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5. CONCLUSIONS
In this chapter, the results from the previous analyses are summarized. These results are compared with the theoretical framework in order to distinguish several insights that this study provided. Moreover a conclusion will be formed, followed by implications and recommendations for future research.
5.1 Discussion
There is an increasing trend towards healthier food products, while obesity numbers remain extremely high. Research regarding consumers’ intentions to engage in health behaviour and their actual behavior are widely discussed and the majority shows a positive relationship. However, these results are inconclusive, and the roles of consumer value orientations and a time difference are researched to explain this relationship. In this study 12 hypotheses are formed, but only four of them could be confirmed. An overview of these hypotheses and their results are shown in table 14.
TABLE 14: Overview of hypothesized relationships and results
Field study Lab experiment H1a Autonomous health motivation has a positive effect on the choice of healthy food products.
ü
ü
H1b Controlled health motivation has a positive effect on the choice of healthy food products.
X X
H2a The effect of autonomous health motivation on choosing healthy food products is stronger when an individual’s egoistic values are higher.
- X
H2b The effect of controlled health motivation on choosing healthy food products is not influenced by an individual’s egoistic values.
-
ü
H3a The effect of autonomous health motivation on choosing healthy food products is stronger when an individual’s biospheric values are higher.
- X
H3b The effect of controlled health motivation on choosing healthy food products is not influenced by an individual’s biospheric values.
-
ü
H4a The effect of autonomous health motivation on choosing healthy food products is stronger when an individual’s altruistic values are higher.
- X
H4b The effect of controlled health motivation on choosing healthy food products is stronger when an individual’s altruistic values are higher.
- X
H5a The effect of autonomous health motivation on choosing healthy food products is weaker when an individual’s hedonic values are higher.
- X
H5b The effect of controlled health motivation on choosing healthy food products is weaker when an individual’s hedonic values are higher.
- X
H6a The relationship between autonomous health motivation and choosing healthy food products is stronger when an individual has to make a decision in the distant future.
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H6b The relationship between controlled health motivation and choosing healthy food products is stronger when an individual has to make a decision in the distant future.
ü
ü
/ XAs expected from literature (McSpadden et al., 2016; Kraus & Piqueras – Fiszman, 2016), both studies confirmed the influence of autonomous health motivation on the choice of healthy food products. The claim that the results are inconclusive and that there is a gap between individuals health intentions and their actual behavior (Burton et al., 2015; Verain et al., 2015; Mullan et al., 2014) still holds, as both studies do not confirm the relationship between controlled health motivation and the choice of healthy food products. An explanation for this gap is that, consumers who are health motivated may not make healthy choices because of competing short-term motives and product attributes, such as ease, taste and price. These short-term food choice motives could overrule health concerns pressured by others. Another explanation for this lack of effect could simply be that impulsivity plays a role in unhealthy snacking behaviour, which could be leading in the decision-making process (Mullan et al., 2014). Lastly, it is possible that individuals are not aware of the healthfulness of some products, and it could be that in their perception they did choose a healthy product.
This thesis was trying to fill this inconclusiveness by studying the potential roles of consumer value orientations and a time difference on this relationship. The consumer value orientations did not significantly affect the relationship. A first explanation could be that, it is difficult to measure the impact of consumer values due to generalizability and abstractness (Vaske & Donelly, 1999; Honkanen et al., 2006), which could explain the insignificant results.
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As expected, no moderating effect of the biospheric value orientation on the relationship between controlled health motivation and choosing healthy food products was found, nor on the relationship between autonomous health motivation and choice. A possible explanation could be that the perception of organic food products is not that related to healthiness as previous research suggested. Thus, eating ‘green’ only leads to the consumption of organic food products (Aygen, 2012; Magnusson et al., 2013; van Doorn & Verhoef, 2015; Kareklas et al., 2014), and not being more motivated to choose healthier food products per se. This suggests that the higher health consciousness among these individuals (van Doorn & Verhoef), does not lead to purchasing healthy food products, but in other ways to perform a healthy lifestyle. Environmental traits of a product could lead to a positive perception of the healthiness of the product, even though the environmental aspect has no effect on the healthiness of the product (Verain et al., 2015). Also a recent research suggests, that the feeling of being good to the environment convinces people to treat themselves to unhealthy food, and thus a positive relationship between organic behaviour and junk food is shown (Bollinger & Karmakar, 2015).
Although a strong moderating effect of the altruistic value orientation was expected (de Groot & Steg, 2010) insignificant results are shown. A possible explanation is that promoting the welfare of others (Bardi & Schwartz, 2003) is done in a different way than by than by choosing healthy food products. Moreover, individuals with altruistic values base their decision to a higher extent on the perceived costs and benefits of this behaviour for other people. When taking the social context into account (Nierman et al., 2015; Makantouni, 2002) this could also translate into thinking that other food products than healthy food products are more beneficial, which results in alternative food options (e.g., organic food purchases or vegetarian consumptions). Although no moderating effect was found, the results did show a positive direct relationship between the altruistic value orientation and the choice of healthy food products. This shows that when focusing on the well-being of known people, they preferably choose healthier food products (Niermann et al., 2015; Makantouni, 2002).
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motivation does not influence their choice of a particular food product. These individuals randomly select their food products, although they have a health vision in mind. Another explanation could be that these hedonic consumers show to be less convinced about the healthiness of food products, which could result in resistance against these food products (Verain et al., 2015).
The role of the time difference on the relationship between health motivation and healthy food decision-making was highly expected (Milfont & Gouveia, 2006; Milkman et al., 2010; Ronteltap et al., 2011; Mullan et al., 2014; Dassen et al., 2015), but only showed significance on the relationship between controlled health motivation and the choice of healthy food products. A possible explanation could be that autonomous health-motivated individuals do not take future consequences into account (Stratman et al., 1994) and are motivated by the short-term consequences of eating foods high in saturated fat, such as enjoying the taste and ease of preparation (Mullan et al., 2014). Not taking future consequences into account, is also possible because individuals rely on their habits and continue showing a similar behavior (McSpadden et al., 2016; Naughton et al., 2015; Nierman et al., 2015). Habits are a powerful determinant of their food choice (Naugthon et al., 2015) and research shows that individuals repeatedly confronted with similar behavioral choice will form cues. This suggests that a time difference does not make any difference, unless the existing habits are broken. Likewise, it could be that these individuals stick to their self-identity (i.e., ‘you are what you eat’), meaning that people infer what kind of person they are from their consumption choices (Thomsen & Hansen, 2015). Research showed that a self-identity independently predicted healthy eating behaviors for fruit and vegetable consumption and low fat diets (Brouwer & Mosack, 2015) and is not influenced by a time difference.
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5.2 Conclusion
This study investigated the relationship between autonomous and controlled health motivation and healthy food decision-making behaviour, and tried to explain the roles that several consumer value orientations and temporal distance play in healthy food decision-making behaviour. It can be concluded that autonomous health motivation does influence healthy food decision-making, where controlled health motivation shows insignificant results. The consumer value orientations did not seem to strengthen or weaken this relationship, where a time difference only showed a positive effect between controlled health motivation and the choice of healthy food.
Academic contribution
This study adds to the academic field since it investigated the moderating role of consumer value orientations and a time difference on the relationship between health motivation and the choice of healthy food products. Overall, results show that both do not show a significant moderating effect. With regard to the consumer value orientations, having strong egoistic, biospheric, altruistic or hedonic values does not strengthen or weaken a health-motivated individual in its healthy food choice. Only the relationship between controlled health motivation and healthy food decision-making behaviour is influenced by making a decision now or in the distant future.
Managerial contribution
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Organisations such as the Netherlands Nutrition Centre could play a great role in educating consumers, developing these campaigns and implementing these marketing strategies in order to stimulate healthier food choices. Retailers should follow these movements, from which they will benefit by consumers purchasing a bigger amount of healthy food products.
On the other hand, the results of this research imply that practitioners should not promote healthy intentions and preferences by strengthening individuals’ values. These value orientations do not affect the choice of health-motivated individuals, and thus do not have to play a role in the development of marketing and communication campaigns that promote good health. Also focusing on the time aspect when consumers have to make a decision themselves is not recommended, as this study shows that consumers do not make a different decision. In situations where individuals feel pressured by others in making a healthy decision, it does make sense to focus on the time aspect. This can be done by rolling out campaigns, which show the behaviour of others (e.g., ‘x amount of people also bought this product’) and a clear timeslot until when the promotion is valid.
5.3 Implications and recommendations
This study has several limitations. Firstly the external validity of the lab experiment could be discussed, as participants did not receive the lunch options they ordered. In the field study participants did receive their lunch options. Another important limitation refers to the sampling method, as both studies included student instead of representative samples. Since age could influence individuals’ values, health motivations and decision-making behaviour, a larger sample of different ages could be used for future research. Furthermore, factors such as price (e.g., affordable) and access (e.g., availability) are not included in this research, but could play a significant role in individuals’ decision-making process of the food products. A fourth issue concerns the overlap in content of the different value orientations in the field study. Although the value orientations were framed in a way that included a clear distinction, results showed that this was not the case for participants. In future research it is important to even more frame these different value orientations in the questionnaire clearly. Moreover, it might be interesting to investigate the influence of more different kind of health motivations on consumers’ decision-making behaviour.
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