Executive summary

This report analyses the consumer decision-making process to assess the potential for creating behavioral interventions that induce large-scale and permanent change in consumers and subsequently, the food system itself.

Consumers are a major force in the global economic system, with their purchases representing about 60% of the world’s GDP. As such, consumer food decisions have important impacts on the food system through their market demand, sometimes determining what food will be produced and by what methods.

People follow complex and seemingly chaotic mechanisms to make decisions and adopt behaviors, with a multitude of factors influencing these. When following conventional economic or marketing models, most interventions to change consumer behavior focus on providing facts and information. They may make use of controversial, reprimanding, or shocking messages to reach their audiences. However, consumers often shun these negative narratives and disregard information related to things they don’t care about or feel unable to change.

To reach consumers, messages should be positive, awe-inspiring, and engaging rather than shocking, framed in terms of loss, or demanding sacrifice. Consumers’ decisions are more readily swayed by positive cues, such as pleasant images and enjoyable experiences. These forms of positive reinforcement are much more effective than negative information, which may be ignored entirely. Most people will not be willing to make sacrifices for the planet or people they don’t know; scale and proximity of target impacts are hugely important when considering behavioral change. Rather than looking at future impacts which seem distant or irrelevant, marketers need to highlight personal benefits. Through diffusion in social networks and media sources, behavioral change can be better targeted and make a larger impact. Rather than attempting to make everyone change at once, it is wiser to target networks that have a greater likelihood of responding to a particular message. This message will then diffuse more broadly with less need for external influence and information provision. In the long term, the ideal intervention is one that establishes desired behaviors as habits and guarantees the external conditions for these habits to occur smoothly and thoughtlessly.

Despite these general guidelines, behavioral outcomes are extremely sensitive to a wide variety of factors, many of which interact unpredictably and not based on static preferences. It is very easy to affect human behavior, but it is hard to accurately anticipate the way in which people will react to behavioral interventions. As such, interventions should be targeted and specific, they should be optimized to harness cognitive limitations, and they should be rolled out alongside complementary structural interventions on the food system: Infrastructure, product prices and standards, economic incentives, and the use of nudging techniques to create convenience. A combination of strategies focussing on different aspects should be used to guarantee the large-scale adoption, diffusion, and establishment of desired behaviors.

While long-term behavioral change is inherently complicated, it still has potential to induce positive systemic change under the right circumstances. Interventions on a consumer level should be applied synergistically with strategies addressing other parts of the food system. Neglecting consumers will reduce the effectiveness of other interventions targeting producers, traders, and regulators because of the interdependence between these groups. Without adequate behavioral change programs, consumers will remain subject to the existing narratives and messages that promote high impact products and behaviors.

Introduction

In 2016, Metabolic published “The Global Food System: An Analysis”, a report commissioned by WWF Netherlands to provide systems level analysis of the food system. The report identified key behavioral patterns and structural causes that result in the negative impacts of the global food system. Metabolic also identified a series of intervention points that could be used to trigger structural change across the system to bring it to a healthy and sustainable state. This report on consumer behavior is an in-depth look at one of these intervention points: changing the everyday food-related decisions consumers make on a daily basis.

Billions of consumers make decisions regarding food, exerting a major force on the structure of the system. This has brought a lot of attention to changing consumer behavior as a strategic area for sustainability interventions. However, these decisions are more complex than they appear and are highly influenced by the context in which they happen.

As discussed in the Global Analysis report, behaviors occur in a dynamic system where consumers interact with producers, farmers, traders, retailers, industries, governments, and a series of other actors. In light of this, and considering the asymmetries of power between these groups, it is inaccurate to think of consumer behavior as the fundamental driver of the market or as the core issue necessary to move our economy to a more sustainable state. Next to these actors, socioeconomic and governance structures play as much of a part, and should be addressed holistically for effective change in the food system. Thus, the best means to guarantee long-term change is to accompany behavioral interventions with changes in the underlying structures and conditions that determine these behaviors, and to address issues across the chain, not on a single type of stakeholder.

Civil society organisations have focused their intervention efforts on awareness and information campaigns to persuade the public to change its decisions on food purchasing. The goal of these campaigns is generally to encourage consumers to change their habits or make personal sacrifices, often for causes that seem distant or personally irrelevant. The style of messaging frequently leans heavily on shocking or depressing content.

For example, PETA’s campaigns tend to use shocking and controversial elements, including themes related to the holocaust, racism, sexual objectification, blood, and animal carcasses to draw attention to their message (Bhasin, 2011; PETA, 2015). The “BeVegetarian” campaign highlighted the contradictory social constructs applied to animals: some are seen as pets and others as food (BeVeg, 2011). While these kinds of campaigns are effective at grabbing the attention of the media, such messages typically fail to cause lasting changes in consumer behavior. The focus on negative information is more likely to cause discomfort and trigger defence mechanisms, resulting in justifications for the continuation of current practices rather than motivating change.

These campaigns are well intended but, in the big picture, their effectiveness is fleeting and questionable at best, as they ultimately work against the nature of the consumer’s mind. For example, one of the most common subjects of ethical and environmental campaigning in the food system is that of meat consumption. While decisions to reduce or eliminate meat consumption have taken root with more engaged and committed consumer groups, macro-level market trends have not shown significant alteration; the overall demand for meat has remained relatively stable in past decades (see page 6 for a more detailed look at meat consumption trends).

Consumer behavior is a complex and dynamic phenomenon based on a very sensitive and unpredictable decision-making process. Due to these characteristics, it is extremely easy to alter the outcome of this process, but it is difficult to do so in a predictable way. However, recent research from behavioral economics and related fields has shed light on strategic ways to improve the effectiveness of behavioral interventions.

The objective of this report is to provide a clear picture of the behavioral process, both at the individual and social levels, and assess the available strategies to steer it to sustainable patterns of behavior. The models of bounded rationality and cognitive biases are useful for understanding human nature and decision-making. We use these models to complement concepts from marketing, economics, psychology, and sociology. Together, these areas of knowledge can be translated into strategies for more effective behavioral interventions that are described at the end of this report.

Consumers & their Behaviour

Consumer behaviour includes all the actions directly related to the obtaining, consuming, and disposing of products and services; from a broader perspective, it also includes the consumption of experiences and ideas, as well as the decision-making and evaluation that precede and follow consumption.

Behaviour follows a cognitive process where decisions are made at the individual level, but social dynamics affect how these behaviours spread throughout groups. For the consumer, behaviour is a tool to meet physiological, emotional, and social needs and desires (Engel et al, 1990; Jeddi et al, 2013).

Consumers have considerable weight in the economy. Household final consumption, which measures the market value of all goods and services purchased by households, represents 60% of the world’s GDP. For 2014, consumer expenditure in the Netherlands was estimated at US $389 billion; 45% of the national GDP. In the US, it was 68% of the GDP, and 64% in the UK (OECD iLibrary, 2009; World Bank, 2015).

Every year, over 30,000 new consumer products are launched worldwide. 90% of these will fail despite market research indicating people are willing to buy them (Policy Studies Institute, 2006). Consumers are heterogeneous and fleeting in their attitudes; they are not a uniform mass of individuals with stable and predictable behaviours. This diversity should not be ignored, but capitalised upon.

Food Consumption

Food consumption behaviours include the acquisition, preparation, serving, storage, consumption, washing, and cleaning up of food (Sobal & Bisogni, 2009). The consumption of food differs from that of other products and services as it goes far beyond utilitarian reasons. At the individual level, food is linked to past memories and, because it is ingested, it is experienced in a very powerful and intimate way. Food behaviour is particularly normative and deeply embedded in cultural norms, often defined by what it is expected to be in its social context. So long as basic needs are met, food choices are determined more by questions of status and identity rather than nutrition and hunger (Dzene & Yorulmaz, 2011). 

Food selection and consumption are also habitual behaviours that will remain generally stable so long as a person does not experience adverse effects like poisoning or disease (Capaldi, 2006). The resulting effect of ideological paradigms, a lifetime of memories, daily automatic habits, and subjective sociocultural considerations make food behaviour particularly difficult to change. Even adverse situations, such as disease, may only have temporary effects. For example, the “mad cow disease” outbreak in the late 1980s, posed a serious threat to human health and led to strong and sudden changes in beef consumption. However, after some months market demand for beef returned to normal (Schlenker and Villas-Boas, 2006). 

Understanding the Consumer’s Mind

Most consumer decisions are not rational; they are subject to cognitive limitations that result in suboptimal decision-making. When consumers decide what to buy, they don’t carefully weigh their options, but take a more pragmatic and even careless approach. 

When consumers decide what food to consume, they give priority to their habits, what they see people around them eat, and what looks and feels appealing. Careful analysis of nutritional and environmental concerns will rarely have importance in the decisions of most people.

Rational Thinking

Consumer behaviour, according to traditional economic models, is understood as a process where self-interested agents rationally consider their options to optimise costs and benefits within certain constraints. These models assume consumers have inherent preferences guiding this optimisation and work under conditions of certainty and full information. Suboptimal results are caused by imperfect information and inadequate signals (such as pricing), so policy and awareness campaigns attempt to provide information and affect the relative costs of goods and services to correct these failures (Department of Finance and Deregulation, Australian Government, n.a.). 

Bounded Rationality

of this process, which questions the assumptions and validity of the rational thinking model. Decision-making is bounded by the cognitive limitations of people and by the available time and resources to make a decision. As a result, people “satisfice,” rather than optimise their choices (Simon, 1955; Jones, 2003). 

Cognitive or psychological biases lead people to systematically and predictably deviate from the optimal results expected of rational behaviour. We are subject to several such biases, the most common ones are listed here (pg. 8). On top of this, rational decision-making is taxing for the mind and people have evolved a series of mechanisms to avoid it altogether. These mechanisms include habits, imitation, and heuristics (such as rules-of-thumb and educated guesses) to assist in this process. Whilst these tools are regularly used, they become more predominant as choice complexity increases (Fishbein & Ajzen, 1975; Policy Studies Institute, 2006; Akerlof & Kennedy, 2013). 

These mechanisms and cognitive biases have evolutionary advantages, as they account for uncertainty and asymmetric costs, for example, by automatically reacting with precaution against a potentially threatening situation. However, as they lead every person to consistently make the same kind of choice as the previous one, they exacerbate the unsustainable burden of certain common behaviours (Johnson et al, 2013). For example, people may react with disgust against old food and reject it when it’s still edible which increases overall food waste. Given the possibility, people will eat more than their needs, as the costs of eating too much are relatively small in comparison to the costs of famine in the future, which leads to overconsumption at the aggregate level. 

Cognitive Biases

People can’t help it that they have certain cognitive biases, instead of fighting against their nature, they can be capitalized for behavioural change. 

Campaigns for change in food behaviour should highlight the immediate benefits for the consumer and their family, especially in terms of status and identity, as well as the popularity of the new behaviour. 

Bounded self-interest

People will prioritise their own interests over those of the group. This has limitations, as shown by altruistic behaviours motivated by social fairness, environmental preservation, or reciprocity. 

Social context biases

A person’s choices will depend on the choices of those around them. People will unconsciously imitate others and follow the social norms around them. Imitation and credibility are asymmetrically biased according to the perceived status, expertise, legitimacy, and authority of the source or referent. People will focus on their relative status (compared to their peers) rather than on their objective status. 

Self-consistency issues

People feel uneasy when they are not consistent with their own images or values. As a result, they try to behave in ways that look positive and are consistent with their self-identities. However, they also have limited willpower and self-control, which leads them to having incoherent preferences. 

Default choice and endowment effect

People prefer not to change. We will make different choices depending on how information is presented. Default choices and the current state are preferred over alternatives. Especially for limited or rare goods (like those of status), people will give higher value to the ones they have in their possession compared to the ones they don’t have. People have loss aversion, and will avoid giving up goods that they possess. 

Future discounting and impalpable concerns

People prefer instant gratifications to future well-being. They also disregard problems that are far away or unrelated to them or their own. 

Priming and thought saliency

Thought saliency, or how relevant an idea is on people’s minds at a given moment, has an important effect on behaviours. Priming, a technique used in marketing, exploits an even stronger phenomenon of thought association by exposing people to sensations linked to desired behaviours. 

Sources: (Fishbein & Ajzen, 1975), (Griskevicius et al, 2012), (Department of Finance and Deregulation, Australian Government, n.a.), (Akerlof & Kennedy, 2013). 

The Behavioural Cycle

The consumer behavioural cycle consists of several steps which are all influenced by a multitude of factors and variables. Before the actual processing phase, a lot of new knowledge and messages reach the consumer, but a significant amount of this information will be filtered out and not impact the behavioural cycle. During the processing phase, the brain uses two complementary systems, central and peripheral, to evalaute filtered information and produce behavioural attitudes and intentions. However, many attitudes don’t materialize in actual behaviours, an inconsistency known as the behavioural gap that is exacerbated by certain environmental factors. When the behavioural gap is avoided and a behaviour takes place, an experience is formulated. A negative experience results in a reconsideration of the behaviour through new processing; while a positive one confirms the attitudes and intentions, and may eventually lead to habit formation. Once habits are well established, behaviour occurs automatically, triggered by environmental cues and without the need for additional processing. 

1. Filtering

Most consumers will subconsciously ignore messages that attack their lifestyles and identity or trigger a sense of repulsion, anxiety or guilt. Consumers react more positively to optimistic, gain-framed messages that come from sources they respect and trust. 

In terms of food consumption, instead of portraying the cruelty of the livestock industry, which will repel consumers, messages should portray the harmony and high status of a vegetarian diet.

The brain protects itself from overstimulation by filtering out most of the information it receives. This process is unconscious, automatic, and unique to every individual. Information filters arise from people’s attitudes, social context, and particular ideas. 

Cognitive biases affect how consumers associate and frame information on the basis of routine thinking, previous knowledge, and consistency with existing beliefs. The level of involvement, or how important the information is to the consumer at the moment, is a deciding factor to let information pass through the filters (Burton, 2009). 

Message-related factors, even superficial ones such as the form and source of communication, are determinant in whether information will get through the brain’s filters. 

Type & Content

A message can be gain-framed or loss-framed depending on whether it tells a consumer they will have benefits or costs and risks from engaging in a behaviour. A message can be directive, motivational, or pleading to sacrifice, and generate enthusiasm or fear to encourage action. 

More people are likely to buy organic food when its benefits are emphasized rather than when the environmental impacts of conventional production are highlighted (Gifford & Bernard, 2006). Gain-framed messages that focus on eating healthfully, and construct positive body image have proven to be more effective than loss-framed messages that point out the negative consiquences of poor health choices (Wansick & Pope, 2014). 

Negative framing, which appeals to human fears and emphasizes an action’s negative consequences, can cause a “boomerang effect” where a consumer takes a choice opposite to the message’s intention (Hart et al., 2011). For example some consumers have been noted to seek out high-fat products, based on information labels, despite the associated health warnings of a high fat diet (Bushman, 1998). 

Particularly effective messages are those that are awe-inspiring, positive, surprising, useful, and gain-framed; while ineffective messages tend to be loss-framed, fear-themed, motivational or sacrificial. People reject content that generates a negative mood or requires them to spend resources (Gifford & Comeau, 2011; Gifford & Bernard, 2005; The American Psychological Association, 2004). For example, the WHO’s 2015 declarations on the carcinogenic effects of processed and red meat are unlikely to cause significant shifts in meat consumption from shifts in consumer behaviour. While it is too early to see any resulting trend, a 2002 declaration by the American Cancer Society had a similar impact on news headlines byt no real changes on meat consumption in the last fourteen years (NPD, 2015). 

Channel & Source

Messages are said to come from formal sources when the agents are not personally acquainted. This includes messaging from the government, media, and educational institutions. Messages that come from informal sources are those where the communicators are friends, relatives, or peers (Johnson et al., 1994). The channel used may be mass communication or interpersonal. Mass communication, especially in traditional media, is linked to unidirectional communication where messages reach people in a fixed way, but the Internet and information technologies have blurred these distinctions. Interpersonal communication can come from formal or informal sources, depending on the context and more easily allow bidirectional communication (McAlistar, 2014). 

Interpersonal and bidirectional messages are generally more effective at passing through consumer’s filters, as they inspire more trust and stimulate active consideration of the information (Werner et al., 2007; Herr et al., 1991). The effectiveness of messages coming from formal and informal sources will depend on the quality and type of the relationship, as well as the perceived legitimacy of the source (Johnson et al., 1994). 

2. Processing

The brain prefers peripheral decision making, which is intuitive and practical, over the rational and resource-intensive central processing system. 

Food decisions are particularly prone to peripheral processing. Most consumers are not willing to spend time and resources thinking about food. They go with what is easy, attractive, and common around them. 

External messages that have succesfullly passed through the mind’s information filters trigger processing in the consumer’s mind. Internal messages, coming from past experiences or present state factors also elicit processing. At the end of this stage of the cycle, a behavioural intention is produced under influence of many factors, variables and cognitive iases. 

Dual processing mechanisms

There are two main mechanisms to process the information that has passed through the brain’s initial filters: central and peripheral processing. It’s commonly said that 5% of our thinking is central and 95% is peripheral, but in reality the two processes are better seen as two sides of a single gradient that are used simultaneously (Petty & Cacioppo, 1986; Evans, 2008). 

1. Central Processing

Central processing is more rational and judges information on its coherence, logical consistency and argumentative depth. The person’s current knowledge and cognitive capacity are key limitations in the quality of the outcome. 

This thinking is systematic, slow, and energy intensive. It requires conscious attention and exerts mental and physical costs, for which it is preferably avoided. Even when it is 

2. Peripheral processing

Factor influencing processing

Certain personal and contextual factors play an important role in determining whether central or peripheral processing will be more dominant. 

1. Internal factors

Socioeconomic and demographic factors affect processing in different ways. Gender, cognitive age, socioeconomic status, life cycle stage, and occupation are of interest. For instance, young age, higher education, and higher income are positively related to willingness to adopt innovative products (Wei, 2005). 

Gender plays a role in how people visualize products they may purchase. Men prefer to see a product by itself, while women prefer to see in different contexts before making a decision. Women are generally involved in two thirds of all household purchases, but this characteristic is weaker in higher education contexts (Principles of Marketing, 2012). 

A consumer’s social status will affect their purchasing decisions in specific situations. Some consumers are willing to be seen purchasing green products, so long as they are more expensive than the normal ones, as a sign of altruism and status (Griskevicius et al, 2010). 

Beliefs and values have important effects on food behaviour. Attitudes towards green and GM-foods are especially affected by ethical and political ideology (Antonopolou et al, 2009). Personality plays an underlying role, as a key determinant in these political positions: people characterised by being open to experience are especially prone to engage in politically-motivated green purchasing; people characterised by being extroverted and agreeable are not. 

Some people, described as “in need for cognition,” are naturally more inclined towards central processing, while other people will prefer to make use of peripheral processing, and will be more exposed to priming and mimicry (Cacioppo & Petty, 1982). Anxious and information-seeking personalities will be more prone to central thinking as a risk mitigation mechanism (Lepri et al, 2012). Other personality traits, such as thrill seeking and the need to maintain a high level of stimulation, are related to peripheral thinking and to impulsive buying behaviour (Gerbing et al, 1987). 

2. External factors

Culture is the most basic determinant of a person’s perceptions, desires, and values. The social norms present in a consumer’s social network are influential in decision making. So are a person’s family, education, (perceived) social status, reference groups, geographical location, and the marketing that is exerted on them (Shepherd & Raats, 2006; Rani, 2014). 

These factors affect emotional management and the relative weight of individual identity and needs in relation to social norms and expectations. People unconsciously imitate the attitudes and behaviours of those around them and select their own behaviours according to the image they want to portray to others (Friedkin, 2010; Principles of Marketing, 2012). 

People in collectivist societies pay more attention to the group’s norms and duties, while people in individualist societies strive for autonomy in decision-making and emphasise self-perceived rational analysis and personal goals in their behaviour (Triandis, 1995; Kacen & Lee, 2002). People living in cultures with high degrees of ethnic identification have propensity to purchase products associated with their own culture (Chattamaran, 2008). 

The behaviour’s level of involvement determines how much effort is put into processing. Behaviours with higher costs, risks, and importance command more central processing. ON the other hand, food is especially prone to peripheral processing, as it is essentially a low involvement and routinely acquired product (Principles of Marketing, 2012). 

Product-specific factors include the relative advantages they offer compared to alternatives, compatibility with existing values and experiences, simplicity of use, and risk and uncertainty reducing factors, like trialability and guarantees. These factors explain between 49 and 87% of new product adoption (Rogers, 2003). Consumers are less likely to buy a product that is complex in use or which is not compatible with their lifestyles (Faiers et al., 2006).

Encoded behaviours

Much of human behaviour is determined by deeply ingrained evolutionary motives important for survival and reproduction. These motives include avoiding harm and disease and forming social relations and status, including acquiring a mate and caring for family (Griskevicius & Kenrick, 2013; Al-Shawaf et al, 2015). 

Interventions for behavioural change should work with these encoded behaviours, not against them. There are two relevant encoded behaviours for food consumption: innate taste preferences and disgust reactions. 

Humans have innate preferences for sweet, salty and umami-tasting food. These tastes signal the brain the availability of nutrients and elicit pleasure and food cravings. On the other hand, sour and bitter flavours are initially disliked, as they signal unripe or noxious elements – most poisons have a bitter taste. Familiar flavours, including those to which babies are exposed prenatally, will also be preferable (Rozin, 2005; JeDesus et al, 2015). 

The food industry exploits these innate preferences to increase consumption. Most notably by increasing fat, sugar, and salt content in fast food to increase appetite and generate cravings (Masic & Yeomans, 2014; Garber & Lustig, 2011). 

Disgust is a powerful reaction evolved to avoid the ingestion of pathogens. It’s most often triggered by unknown food, especially of animal origin. Some sensory cues, such as the smell or colour of rotten meat, will automatically trigger disgust. These reflexes are thought to be established between the ages of five and eight and may result of conditioning from previous experiences. However the relation is still unclear and under study (Rottman, 2014; Al-Shawaf et al, 2015). 

Disgust reactions can act as a strong barrier to accept unfamiliar foods. For instance insect food is highly controvertial in western society because bugs are associated with pathogens and disease. 

Encoded behaviours are strong and unconscious, and have very low activation thresholds. They are not easily dissuaded with information or arguments. In the human mind, ancient evolutionary functions, such as our embedded behaviours are much stronger than recent ones, like high cognition (Tybur et al, 2012; Tybur et al, 2013). 

Identity-based behaviour

Consumers adhere to self-identities: subjective ideas and labels with which they associate. These labels can be stable or transitory and represent what the person is, should be, or wants to be. Identities are anchored in referents, which include groups, opinion leaders and role models, as well as abstract concepts, and can be real or imaginary (Reed II et al, 2012). 

A consumer will hold different identities, many of which will be complementary and contradictory. Which one is influential in a particular decision depends on several factors: how present they are in the consumer’s mind at that particular moment, to what stimuli they are associated, and how relevant they are for them (Reed II et al, 2012). 

Identities are automatically triggered by both environmental and product cues and have some flexibility in their meaning. This can be exploited to change food behaviour by highlighting relevant traits and characteristics in the product that are important for the target audience. Publicity can portray celebrities or people with expensive lifestyles consuming a particular food, exploiting aspirational identities to promote the product. The same rehydrating drink can be associated with athletes or industry workers, depending on how the messages are presented. People may identify with aspects of one of these lifestyles and be more likely to acquire the product if it suits part of their sense of idenity. 

Individual and social identities have a powerful effect on behavioural outcomes, affecting intention to buy organic food and aspirational purchases, and are a major source of social motivation (Hustvedt & Dickson, 2009). This is because people constantly monitor and manage their own behaviour to be consistent with their identities. 

3. Attitude & Intention

People can have a positive attitude towards sustainable food, but that doesn’t mean they intend to consume it. Attitudes and intentions are unstable and malleable; an obstacle and opportunity for behavioural change. 

Processing will result in a specific attitude, positive or negative, towards the message object or past experience. Attitudes formed through central processing will be more strongly held by people and are likely to contribute to their self-identity. Peripherally developed attitudes tend to be less stable and conscious (Grunert, 2011). 

The strength and presence of attitudes fluctuates over time. Stronger and more salient attitudes have many associations, high personal relevance, are based on personal experience, and have been expressed repeatedly and publicly. These are accessible in memory and more relevant in behaviour (Fazio et al, 1989; Grunert, 2011). Attitudes are an intermediary between the processing mechanism and the resulting behavioural intention. Intentions are the actual commitments people have towards behaviours and they’re formed of attitudes, subjective norms, and perceived behavioural control (Bagozzi, 1981). 

A behaviour is likely to be rejected if it is not coherent with the consumer’s beliefs and values or if it is not persuasive enough, if it appears foreign to the receiver, if the message is loss-framed, aggressive or conflicting, or if it is excessively frequent and results in fatigue. These factors can also lead to a boomerang effect where a consumer reacts in a way opposite to the message (Gifford & Bernard, 2005). 

However, if a message is successfully accepted it can lead to a new behavioural intention, either for one a time experience or a long-term change. 

4. The Behavioural Gap

When consumers have positive experiences, they are more likely to repeat the behaviour and, in the long-term, turn it into a habit. 

The context in which food is experienced can be altered to improve people’s experience. Sustainable food should be offered in pleasant, feel-good, visible situations and accompanied by positive feedback and rewards. Convenience and positive experiences can then become habitual food consumption. 

Once the consumer carries out, or not, the behaviour in question, they will register a positive or negative experience towards the behaviour. Whether the experience is registered as negative or positive will determine the likelihood of the consumer repeating the behaviour or rejecting it in future occasions. There is a variety of internal and social factors that influence the experience of the behaviour. 

Behaviours that result in positive experiences are likely to be stabilized into the future and possibly become habits. Behaviours that result in negative experiences will be rejected, with the person returning to previous habits or continuing to seek satisfying alternatives. 

For example, replacing meat with a meat-substitute can give a negative experience to a person and lead to reconsideration of their initial motivation for eating less meat, or it can give a positive experience. This will lead to repetition of the behaviour and eventually to habit formation of eating less meat. As explained below, multiple factors play a role in what the experience will be (Schösler et al., 2012). 

Factors influencing experience & habits

1. Internal factors

The consumer’s reference levels, which originate from their previous behaviour and experiences, are important key determinants in how behaviour is experienced. A consumer will also evaluate the behaviour against their identity, beliefs and values for consistency. Consistency leads to positive experiences. Internal factors such as health and emotion at the time of the behaviour are also influential. 

Contextual information, including social, political, religious, and others, will affect not only food selection, but also taste preferences and neural response to food (DeJesus et al, 2015). Even the position of the body will affect the experience. For example, pushing down on a table while tasting a drink for the first time will have a negative effect on the experience, while pulling up towards the body will have the opposite effect. This happens because the brain associates these positions with attracting or repelling objects from the body (Föster, J. 2003; Föster, J. 2004; Kahneman & Tversky, 1979). 

2. External factors

Factors important to define the experience stage include the actual affordability, availability, accessibility, and attractiveness of the behaviour. High involvement products tend to cause post-purchase dissonance, where people are more likely to feel insecure about their choices and have a negative experience (Principles of Marketing, 2012). 

People can manage around seven different choices in their short-term memory. When there is a larger set of choices, people register a high opportunity cost for the choice. The more options there are, the more options they have reject, and the higher the loss they register. This leads to lower satisfaction with the behaviour and is called the Tyranny (or Paradox) of Choice (Schwartz, 2004). 

The infrastructure and technologies available, which partly determine the quality and other characteristics of a product, as well as the social feedback a consumer receives from the behaviour, and the perceived social acceptance and status gained by a consumer play a role in defining the experience (Staats et al., 2004; Thaler et al., 2014; Griskevicius et al., 2012). 

Habit formation

Habitual food consumption constitutes half of total food consumption (Naik & Moore, 1996). A habit is an automatic behaviour that occurs without much conscious thought as a learnt automatic response to contextual cues. When a behaviour is repeated in a consistent setting and produces a rewarding experience, it becomes ingrained, proceeding more efficiently and being automatically triggered by the associated cues (Lally et al, 2009; Judah et al, 2013; Duhigg, 2014). 

Food consumption is a daily behaviour linked to immediate positive experiences which makes it particularly prone to habit formation and even addiction. Sweets, carbohydrates, fats, and possibly salt, for example, are related to the release of dopamine and opioids and even structural changes in the neural system (Avena et al, 2008; Corsica & Pelchat, 2010). 

As habits do not require conscious thought, they are unlikely to be interrupted by distractions and cognitive burdens (Mann et al, 2013). Deeply established habits can be an obstacle to change behaviour. Eating habits are hard to change and dietary regimes hard to follow. At the same time, habits can be used to protect desired behaviours from further change or to securely establish long-term behavioural change (Gardner, 2013). 

The best way to break a habit is to identify and modify the associated cues and experiences surrounding it. The quickest way to establish a new habit is to chain the desired new behaviour with an already established behaviour. This is called an if-then plan, where if a certain action happens, the person will then do the new one as well. With time, these chains can develop into routines and habits (Duhigg, 2014; Webb et al, 2010). 

From an intervention point of view, habit change should focus on establishing new habits instead of trying to deconstruct existing ones. This is best achieved by restructuring the environment and cue exposure. A behaviour can become a habit after one to six months of repetition, depending its complexity (Gardner, 2013; Lally et al, 2009).

Social Spread of Behaviour

New and sustainable food should be targeted to market segments to maximize its acceptance. Social networks – online and offline – are one of the most powerful diffusion mechanisms for new behaviours. Widespread diffusion of food behaviour can lead to the establishment of new social norms. 

Individuals do not act independently; their decisions happen in a social context that helps behaviours diffuse, stabilize, and normalize across groups. At the broader social level, behaviour is a dynamic and unpredictable phenomenon with different points of equilibrium where the behaviour of individual agents is consistent across the group and time (Flores et al, 2012). 

Social cascades

Behaviours diffuse or cascade through social structures. Diffusion rates look like an S-shaped function where the likelihood of one person adopting a behaviour increases as more people around them have adopted it (Centola and Macy, 2007). Social cascades can explain the successful spread of behaviours in a society (Lepri et al, 2012). 

Part of this adoption process is due to priming and unconscious mimicry, a phenomenon called the chameleon effect (Chartrand & Bargh, 1999; Lepri et al, 2012). Adoption is encouraged by social proof, or a decrease in uncertainty after seeing others practice the behaviour, by the sense of group affiliation it provides (Zilberman & Kaplan, 2014). Complex behaviours have higher adoption thresholds. The harder the new behaviour is, the higher the number of people needed to provide social proof (Contractor & DeChurch, 2014). 

There are two types of social structures that can be leveraged to initiate behavioural cascades: Social networks are used to determine which interaction and interpersonal communication channels are available in a group; Structural segmentation classifies people according to their product-specific attitudes. 

Networks: Intra-group connectivity

Social networks are defined by the interactions between different individuals in a group; these interactions are dynamic and context dependent. The structure of social networks dictates the pathways for information to spread in a society. Individuals are connected to a limited number of people around them. These connections are not randomly chosen but require some shared connection, which generates self-selection, clustering and eventually homogenisation and group auto-correction (Flores et al 2012; Snijders et al, 2007). 

People have different levels of centrality in a network, which is a measure of a node’s connectivity and importance in relationship to the others. Centrality can be exploited to enhance social diffusion over a network. People with high number of connections, access to different groups, or in power positions, have higher centrality (Contractor & DeChurch, 2014). 

Since influence is exerted asymmetrically between a network’s nodes, opinion leaders and other people in vertical relationships have the most effective centrality. Verticality occurs where one person has more power or legitimacy, either from authority, expertise, or hierarchical position (Gatica-Perez, 2009; Friedkin, 2010). Opinion leaders in particular exert their verticality as “processors” of the information distributed by mass media (Contractor & DeChurch, 2014). 

Celebrity-endorsement is an example of opinion leaders promoting a specific behaviour. Through social media celebrities and politicians show their preference for a specific product or behaviour, thereby give the product credibility and make it cascade through their networks. The affinity people have with the famous influences their attitude; “if the product is good enough for her, it’s good enough for me” (Erdogan, 1999). For example, Nestlé has used celebrity George Clooney to promote its coffee (McCann, 2006). 

Segmentation: The innovator-adapter continuum

There are two types of consumers with respect to new behaviours or product acquisitions: innovators and adopters. Innovators purchase novel items impulsively, independently, and perhaps haphazardly. They have low requirements of social proof. While they are willing to try new behaviours, they will drop their current ones easily, not forming habits (Foxall, 2005). 

Adopters will show two patterns of behaviour. Those who have high involvement in the field or have low risk aversion will act as early adopters, being likely to try new behaviours and retain them as habits if they feel a positive experience (Foxall, 2005). Those who are not interested in the product field will be suspicious of new options and reject them initially. These will act, if anything, as late adopters once the behaviour has reached enough people to convince them as well (Foxall, 2005; Rogers, 2003). 

Each segment has different needs and concerns. As each segment requires different messages to be convinced of adopting a behaviour, it is important to know the degree of adoption in a society to communicate succesfully about it (Rogers, 2003). 

Normalization

Behaviours that have become accepted in a society and established as habits for many people can become normalised, acting as part of a society’s unspoken rules and agreements. Social norms serve to regulate behaviour in a group and are self-reinforcing. Humans are hardwired to develop and adhere to norms, as these reduce uncertainty. Norms appear in particular circumstances and can be stable across time regardless of whether they are beneficial or not (Boyd & Richerson, 2002). In the context of food, social norms determine which foods are acceptable and which are not. Unspoken rules affect the preference for large meals or small ones, the proper way to cook and prepare food, or what is considered of higher quality or class, among a myriad elements that comprise food behaviour. 

Normalization happens through imitation, confirmation biases, and consensus-adoption. Imitation requires a certain amount of interactions to happen, so it is prevalent in tight clusters and smaller groups. In groups that are too large, new behaviours are likely to dilute. Once an initial cluster has adopted and normalized a behaviour, it is more likely to spread to neighbouring clusters (Boyd & Richerson, 2002). 

It is important to consider that modern information technologies are creating important changes in social structures and connectivity, and behaviour normalisation plays out differently in information-age societies. 

Case studies

Current trends for meat consumption and organic agriculture

The consumption of insects and organic foods are interesting for their potential to reduce the negative impact of the food system. We study how both cases have been promoted to the public to contextualize the successes and limitations of these behavioral interventions.

The livestock sector is responsible for over 14.5% of anthropogenic greenhouse gas emissions. This is one indication of the ecological benefits that could be achieved through reduced meat consumption. Increasing insect consumption is a potential means to reducing demand for conventional meat industry products (FAO, 2013).

A different greenhouse gas, nitrous oxide is mainly emitted via agricultural practices. A shift toward organic agriculture is one pathway for significantly reducing some of the environmental impacts of food production (FAO, 2002). Consumer acceptance and broad market demand for alternative products are essential for the broad adoption of these or similar strategies.

Meat consumption per capita has seen changes in both Europe and the United States. After decades of growth, total consumption peaked in the US in 2007, after which it has seen a negative trend. This is explained by two factors: the economic recession that started in 2008 and a growing awareness of the health impacts of meat consumption (Packaged Facts, 2013). In Europe, total meat consumption has remained relatively stable, at lower levels than in the US. Beef consumption in particular has decreased in the last 30 years in several major economies: France, Germany, the Netherlands, the United Kingdom and the United States; while poultry has generally gained importance in diets.

Meanwhile, organic food is successfully transitioning from high-end and alternative niches to ubiquitious prodcuts. In the United States, sales increased by 53% between 2009 and 2014 (Packaged Facts, 2014). The US and Canada hold 7% of the world’s organic agricultural land, while Europe accounts for 27%, and Oceania for 40%. Switzerland, Denmark, and Luxeumbourg have the highest per capita consumption or organic food (FiBL & IFOAM, 2015).

Entomophagy: an intervention in processing

Entomophagy, the eating of insects as food, is heralded as a nutrient and protein-rich alternative to conventional meat (Yen, 2009). As recognition increases about the unsustainable nature of industrial livestock and meat production, the popularity of entomophagy is slowly growing (Hartmann, 2015).

In various parts of the world, eating insects is normal. In 36 African countries, more than 524 species are part of the normal diet and may contribute over 50% of dietary animal protein (Raubenheimer, 2013). In contrast, rates of insect eating in the West are much lower. Forty-one species are eaten across 11 European countries. This lower consumption is the result of long standing socio-cultural barriers, like food taboos, as well as psychological barriers, like the fear of new foods (Verbeke, 2015).

Educate, inform, and spread knowledge:

Most insect food that is currently available to consumers is marketed on grounds of its nutritional content and sustainability benefits (Deroy, 2015). However, studies show no effective relationship between provision of information and willingness to eat insects. Education has not significantly altered consumer behavior, as diets are subject to sociocultural norms and knowledge is unlikely to alter this (Lensvelt, 2014).

Change consumer perception:

One of the largest issues to promoting entomophagy is the perceived lack of attractiveness of insects (Deroy, 2014). In the western world, insects are associated with death, illness, and contamination, which trigger a disgust response. As western media spreads around the world, so does this cognitive association (Hartmann, 2015).

People are more willing to eat insect products when these have been ground into a more visually palatable form. Multiple studies have highlighted the increased success of insects as food when they are processed into other goods (Deroy, 2014; Hartmann, 2015). When the sensory cues reminding of the insect content are removed, the cognitive associations of disgust become weaker and attractiveness increases (Lensvelt, 2014)

Raise consumer involvement & change norms:

In cultures where entomophagy is common, the activity is associated with communal practices (Raubenheimer, 2013). Social participation in the harvesting, cooking, and sharing of insect food reduces the disgust factor. Interactive and hands-on family workshops and communal activities in Western countries have been successful at reducing insect disgust and making it a socially acceptable meal (Deroy, 2015).

Strategize around consumer lifestyle/image:

A final technique employed to help increase the willingness to try insects as food is “image” creation, where specialists or respected figures in the gastronomic world create new associations for insect food. This process enhances the credibility and reduces the perceived risks of eating insects (Deroy, 2015). A variety of cookbooks are now dedicated to insect food and respected chefs are hosting large dining events to enable consumers to try insect food in a refined context. These efforts have demonstrated positive responses from the “foodie” world and are helping to shift cultural biases against insects.

Entomophagy today:

Currently, entomophagy has widespread support from the scientific community and environmental and international organisations. Consumers are aware of its nutritional and environmental benefits and insects have popped up as specialty ingredients in restaurants, so much that they have been identified as a “coming trend” in the food industry (Baum+Whiteman, 2015). As can be seen in the graph below, interest in entomophagy has been sparked by the media and international community, but the interest and awareness have not translated to large-scale buying behavior. Overcoming the disgust reaction and cultural issues stand as the major barriers to adoption (Shelomi, 2015).

Organic food: intervention in the behavioral gap

Organic food is one of many suggested tools to reduce some of the environmental impacts of food production practices across the world (Broberg, 2010). The increased recognition by EU consumers related to environmental challenges and the value of organics has spurred market demand for these agricultural products. Between 2003 and 2013, the global market for organic food grew 250% to have a total value of 45.8 billion, with 47% of the consumption in Europe (Marian et al, 2014).Various institutional policies in the EU have assisted these developments, with a large focus placed on the role of consumers (Marian et al, 2014). Whilst various studies have shown that the market is indeed growing quickly, intention to pay a premium for sustainable products does not always translate to actual purchasing behavior (Sandhu, 2010). Various tools and techniques have been used to help reduce this gap between intention and behavior.

Change perceived effectiveness & clarity of outcome:

Effectively motivating consumers to change their habitual purchasing practices relies on their ability to recognize that this change will have a genuine impact. Consumers are unlikely to spend additional resources on a product whose value is not clear (Vittersø & Tangeland, 2015). EU member states have adopted a variety of certification and labelling schemes to assure consumers they are purchasing a product with reduced impact (Madar & Neacsu, 2013).

These tools guarantee that organic production standards are maintained and provide visual cues to consumers that communicate the product’s quality (Madar & Neacsu, 2013; Rousseau & Vranken, 2013). For example, the Swedish KRAV eco-label has been one of the most effective organic labels to date, providing consumers with knowledge and trust in organics (Broberg, 2010; Eurostat, 2015). It is a public-private partnership, which has increased the legitimacy of the certification body (Vittersø & Tangeland, 2015). In 2012 the Swedish organic market was the second largest in Europe and it was worth €917 million (IFOAM EU Group Stats, 2015). Labelling is not the only factor behind the success of organics, as supply-oriented policies worked in tandem with these demand related interventions.

Change certainty of outcome:

Another important aspect of influencing behavior is the certainty of impact of adopting a product (Marian, 2013). Advertisements based on the health benefits of organics and the negative impacts of conventional food have increased consumers’ willingness to purchase these products (Pieniak, 2010). Information campaigns are a popular means to provide this information (Sønderskov & Daugbjerg, 2011). These campaigns provide knowledge via seminars, schooling programs, and social media. While the long-term effectiveness is uncertain, short-term studies have demonstrated positive results. For example, Belgian consumers were willing to pay a premium for organic apples once informed about the environmental and health benefits (Vittersø & Tangeland, 2015). Studies have also recognized that if the relative premium is perceived as too high, even informed consumers might revert to conventional produce (Vittersø & Tangeland, 2015).

Changing affordability:

Due to the economic nature of food market, the affordability of organic produce varies significantly across the EU (Gunnar & Tangeland, 2015). In 2012, Denmark had the highest share of organic produce in the world and continues to implement policies that increase supply, lowering the cost of organic produce for everyday consumers (Sønderskov & Daugbjerg, 2011). This reduces one of the most significant factors of the behavioral gap, which is the affordability of organic food. The Scandinavian approach combines incentives for farmers with demand-oriented policies that target consumer change (Vittersø & Tangeland, 2015). In contrast, initiatives in the US and the UK have focused only on encouraging demand, which has created a less dramatic growth (Sønderskov & Daugbjerg, 2011). In short, although these techniques are important for increasing demand for organics and reducing the behavioral gap, broader integrated approaches appear to create more substantial, sustained and systemic impacts.

Organics today:

European countries lead the organics market and industry. 5.6% of the EU’s arable land is dedicated to organics production, the highest share in the world, and Europeans constitute half of the global organics market (Meredith & Willer, 2014). In Western Europe, barriers to further adoption and purchases include limited availability for regular users, while lack of trust in institutions, lack of information, and lack of interest still remain a problem for new consumers (O’Doherty Jensen et al, 2011). In Eastern Europe, barriers to adoption include lack of institutional support and chain development, but on the consumer side there is a poor acceptance of price premiums and lack of trust in certification bodies (Larsson et al, 2013).

In the United States, support for organics lags far behind Europe but has been growing quickly. 84% of the people purchase some organic product, but supply is insufficient and remains a barrier to larger adoption (Organic Trade Association, 2015).

Strategies for Changing Behaviour

A combination of intervention strategies is the best option to create long-term behavioural change, as each type of strategy is optimal for different objectives. 

Constructing effective messages that match form and content with target and objectives is necessary to reach consumers. Strategies that influence processing and adoption must be combined with strategies that enable and stabilize behaviour.

A multitude of factors and variables influence consumer behaviour, many of these are situational and person specific, which makes behavioural change hard to foresee and influence. The potential to influence consumer behaviour in the long-term is limited by the complex dynamics around consumer behaviour. 

As such, there are important points to take into account in any general behavioural intervention: change is most effective if it happens gradually; interventions should focus on creating new behaviours instead of stopping old ones; facilitating the desired choice is more effective than relying on willpower or motivation; the context and environment play a major role in decision-making; the desired behavioural change should be concrete, not abstract; interventions should happen consistently and iteratively (Persuasive Tech Lab, 2015). . 

For example, instead of asking consumers to give up meat completely, ask them to start with one meatless day a week; instead of asking consumers to stop using plastic bags at the supermarket, give them a nice fabric shopping bag. It is difficult for consumers to remember and act on their motivation every moment of the day, but using smartphones in shops can help them to make the right choice. Stimulating consumers to eat more fruit and vegetables in a low-income neighbourhood will not work as long as they do not have the money to afford them; instead of giving consumers the abstract goal of eating more fruit, ask them to eat two pieces of fruit each day. 

This report now presents a series of concrete strategies to improve the efficacy of any intervetion. Individual strategies for behavioural change must be coherent in the message form and content, the objective or desired behaviour, the creation of supporting conditions, and the characteristics of the target consumer. An overarching-strategy will combine the individual strategies, as they each have different advantages and disadvantages, and serve different purposes in a broader intervention. 

Depending on specific factors, strategies vary on different levels of potential impact but also of feasibility. To improve the overall effectiveness of an intervention, a set of strategies that combine high feasibility with high impact should be chosen. The feasibility will depend on the costs of the strategy, the time for it to take effect, and the benefits it may present to actors, as well as institutional barriers. As for the impact, important factors include the scalability of the intervention, the long-term effects, and the extent of structural change induced. Both the feasibility and impact of a strategy have to be assessed on a case-by-case basis, as these are extremely context-dependent. 

It’s clear that changing the behaviour of consumer markets is a challenging task that requires coordinated interventions at different parts of the system. The right mix of interventions necessary will depend on the current state of the market: what’s the level of adoption and maturity of the product? what are the availability, affordability, accessibility, and attractiveness of the product in question and its potential substitutes? what are the existing price signals, incentives, political interests, and other institutional factors affecting production and consumption? what role are cultural and idiosyncratic factors playing? These factors are particular to every market-product pairing and need to be taken into account to craft effective strategies to change market behaviour. 

Effective messages & communication

strategy, since it determines whether information will go through a consumer’s filters and reach an adequate processing mechanism. To achieve this, the form and content of the message must match the general cognitive biases of people and the particular characteristics of the target consumers. It is important to include an adequate amount of information and arguments when central processing is desired, and to make use of sensorial cues and bounded rationality triggers when peripheral processing is desired. 

Examples of messages that don’t match with people’s tendency towards self-interest are those that implore people to value the group over themselves or that urge self-restraint for the sake of the environment. On the other hand, messages that match this tendency include those that highlight the benefits to a person’s genetic self-interest, threaten a person’s reputation, or foster group identity. Messages that present local, visible environmental problems have a potential to create actual response in consumers. Creating visible links between behaviour and its immediate environmental consequences will enable consumers to see and feel problems and will increase their willingness to accept behavioural change. Presenting distant environmental problems or showing dry statistics mismatches with the natural tendency of impalpable concerns (Griskevicius, 2012). 

Finally, it is important to select adequate sources, channels, and methods of communication. Interpersonal discussion is effective for transmitting knowledge, but it is resource intensive and only feasible with already engaged consumers. On the other hand, peer networks offer social proof and permit fast diffusion of behaviours, given that key nodes have adopted it. Mass communications can reach many people and allow careful construction of the message, but will ultimately influence only a small portion of their audience. 

10 Strategies

These ten strategies for behavioural change address different issues along the behavioural cycle and social spread mechanisms. The first seven are presented from the most centrally-processed strategy (argumentative persuasion) to the most peripherally processed one (priming), the following three work on the establishment and spread of behaviour. However, they should be seen as a continuum of complementary and partially overlapping strategies whose effectiveness depends on synergies with each other. 

1. Argumentative persuasion

Argumentative persuasion is the strategy most often used in awareness campaigns. The objective is to inform people of the consequences of their choices. Logical arguments are accompanied by information and data. As discussed before, this information will not reach most consumers, but only the ones that are engaged in the topic. For this small group, it may be the most powerful behavioural intervention. Given this, argumentative persuasion should be used selectively with specialists, policymakers, opinion leaders, and people who have interest and high-involvement in the topic. Even with argumentative persuasion the cognitive biases, such as discounting future impacts, should be taken into account. 

The advertisements of Becel, a dutch butter company, often include a message on the dangers high cholesterol and are thereby trying to convince people to rationally buy their cholesterol-lowering product (Becel, 2015). 

2. Economic & Regulatory instruments

Public policy instruments, including economic and regulatory instruments, are the strategy of choice for governments and public bodies, given their unique authority to impose taxes, subsidies, incentives, other instruments. These instruments address market failures by correcting the price structure, mostly through the internalization of costs, or by altogether removing choices. These instruments are especially useful to change a behaviour’s availability, accessibility, and affordability. 

In Australia there is a ‘Nutrition in schools policy’ in place, which obliges school cantines to offer healthy, nutritious foods and has a black-list of unhealthy products which are not allowed to be sold (NSW, 2015). 

These instruments are not always effective; people will modify their behaviour only according to the elasticity of the behaviour. Changes in the regulatory and economic structures are powerful and pervasive, reaching all consumers in their jurisdiction. However, imposing these measures is time demanding and not always politically feasible or economically justifiable. Contrary to belief, policy instruments are not a universal solution and must be used selectively and in tandem with other interventions. 

In 2011 the government of Denmark enforced a so-called fat-tax in order to reduce the consumption of foods linked to obesity (BBC, 2011). However, already in 2012 the tax was abolished because it failed to change eating habits, encouraged cross border trading, put jobs at risk, and had been a bureaucratic nightmare for producers and outlets (BBC, 2012). 

3. Doubt assuaging

The focus of this strategy is to reduce consumer doubts in terms of risk and certainty of outcome, which are major factors not only in the processing part of the cycle, but also in the behavioural gap. A variety of techniques can manage this, including labelling and certification schemes, offering guarantees, and spreading information that conveys an action as impactful or socially common. The techniques will differ greatly per type of perceived risk or uncertainty (financial, performance, physical, psychological or social). They improve perceived consumer effectiveness and allow consumers to adhere to social norms and expectations more easily. 

Some of the most important elements for these strategies to work are the use of positive and easy to recognize images (instead of a long list of information) and the use of messages that invite to change through minimal effort (rather than putting consumers in conflict with themselves rather than putting the consumers in conflict with themselves). 

An example of a doubt assuaging strategy aiming to have consumers buy more fairtrade products is the Fairtrade International label. As this label has clear principles and strict standards for assessing products, the consumer is assured of buying an actual fairtrade product that will have positive impacts for producers and not being fooled by an intermediary or other agent trying to make more profit. The consumption of fairtrade products is rising rapidly since the introduction of these labels. World-wide sales of fairtrade certified cocoa rose from 1153 tonnes in 2000 to 10299 tonnes in 2008 (FAO, 2009).

4. Shepherding

Shepherding describes the careful interventions that leverage small group dynamics to encourage behaviour adoption. Small groups provide opportunities for risk reduction through social proof, identity-based behaviours, creation of public commitment and goal setting, motivation out of reciprocity between the parts, and even healthy competition where high-performers can be distinguished and rewarded. While these situations happen naturally in close-knit communities, we use the concept of “shepherding” to describe the steering nature of an intentional behavioural intervention that works hand-in-hand with communities, for example, organising workshops, social events, and support groups. 

Shepherding is a resource intensive, but effective mechanism that can create lasting effects if the behaviours are accepted in the community. It can also be a first step to larger behavioural diffusion through normalisation, social networks, or behaviour adoption. 

With the ‘Food Revolution Day’ campaign of the Jamie Oliver Food Foundation children are in school interactively taught how to cook and consume healthy and nutritious meals, through the means of cooking workshops and classroom exercises (Jamie oliver food foundation, 2015). 

Let’s Move! is a governmental campaign in the USA, launched by Michelle Obama, aiming at more movement and healthier diets for kids through local, interactive events. Involving schools, towns, parents etc. Street-closings to play out-site and a national, healthy dinner are examples of events they have organised (Let’s move, 2015). 

5. Image editing

We group several strategies under the umbrella term image editing, but all of them rely on changing the way behaviours are perceived by people, highlighting their attractiveness, pleasantness, symbol of status, or identity-associations. Image editing does not try to alter the consumer’s decision-making; it makes the behaviour more desirable by itself. 

Image editing techniques are common in marketing, where they are also known as re-branding. For image editing to be successful, the aspirational and self-identity choices of the targets must be identified first. 

Got Milk? is an american campaign aiming to stimulate milk consumption by promoting it as a product widely consumed by famous people. By having famous, idolised people promote the product, drinking milk receives a higher status (Got Milk?, 2015). 

6. Nudging

Nudging includes the strategies most strongly backed by behavioural economists. It takes the cognitive biases of people and exploits them to stimulate people towards a desired choice without restricting their freedom. Nudges are often environmental interventions that alter choice configuration to make the desired choice the default. 

Nudging relies on strong peripheral processing to take default and convenient options, but it must be noted that it does not create effective behavioural change, as the new behaviour will only be chosen so long as it is the default one. A new change in choice configuration would lead consumers to take other options, even revert to previous ones. As a result, nudging must be combined with other strategies that include mechanisms to establish behaviour for longer time frames. 

Restaurants are listing tofu and tempe under the meat options to increase vegetarian consumption. Supermarkets are reorganising their shelves to increase organic and healthy food purchase (Retailnews, 2015). In train stations in the Netherlands, a sign stating how many consumers have already bought fruit increased subsequent fruit purchases (Brandes, 2012). Reducing standard portion sizes in school canteens and offering more whole grain options and fresh fruits is nudging children towards healthier lunch meals in the USA (USDA, 2012).

7. Priming

Priming uses sensorial cues to elicit specific behavioural responses, priming is the one strategy in this list where peripheral processing will be strongest. Priming alters the standards by which alternatives are unconsciously evaluated. It is a very powerful strategy that triggers encoded behaviours, and is often used in the food industry, as the body reacts easily to sensorial triggers. 

While priming can be a burden to fight food overconsumption and the rejection of novel foods, it can also be harnessed or prevented to make desired behaviours more appealing. The best example of which would be the processing of insects into flour, as discussed in the previous section. 

Priming is used in many food advertisements to enhance appetite. Pictures are shown of delicious food, making people feel hungry and increasing the chances that they will buy the product. Showing commercials of fast food has been proven to prime food consumption (Harris et al., 2009). 

8. Enabling conditions

Enabling conditions refer to the contextual situations and individual skills required to prevent a behavioural gap. These include the accessibility, affordability, and availability of a choice; the required infrastructure and technology; and available skills and know-how for consumers to carry out a behaviour. 

Infrastructure is of particular relevance because it also has a function in many other strategies, such as nudging, and it is usually in place for a long time. This makes it a very powerful tool to establish long-term behavioural change. Whereas skills and know-how are useless if they are not accompanied by other strategies that tackle the processing part of the behavioural cycle. 

Subsidizing healthy food to increase its affordability has been proven to be an effective strategy for increasing fruit and vegetable purchase and consumption. Of twenty different, international subsidy programmes applied on different types of foods, 19 proved to be effective in increasing healthy consumption (Ruopeng, 2013). 

For instance, according to a report prepared for Congress by the Economic Research Service of the US Department of Agriculture, about 2.2% of all US households live more than one mile away from a supermarket and do not own a car (USDA, 2009). These people live in the what are called food deserts, where residents do not have access to affordable, healthy food options (especially fruits and vegetables). Food activist in Chicago have for example sought to eliminate food deserts in the city by opening food co-ops in underserved areas where supermarkets have historically been unsuccessful. In addition to selling fresh and organic fruits and vegetables, bulk whole grains and beans, and soy-based meat substitutes, some of these stores also offer cooking and nutrition classes to educate the public about making healthy food choices (Ogburn, 2011).

9. Positive feedback

Rewarding good performance and ensuring positive experiences are essential to guarantee the continuation of the desired behaviour in the future. Techniques to do this include providing live and social feedback of good performance and recognition of success, increasing the visibility of high achievers, and organising fun activities to launch a new behaviour. While they may seem circumstantial and laborious, these techniques can play a big part in the formation of habits and contribute to social spread of behaviours. 

Supermarkets are using the strategy of visibility of good performers by selling fabric bags from their biological brand. These bags show the customer is conscious about the environment and buys biological products. The clear visibility and message on the bag will act as a positive reinforcement for the effort the consumer made to buy biological food and bring their own bag (Blue&Green, 2013). 

Supermarkets have considered using customer-specific purchase data to offer social feedback of their diet, comparing it to that of the average consumer. By praising healthy or sustainable consumption, they could support these behaviours (Foodmanufacture, 2015). The energy sector is already using this technique by giving insight into the average monthly energy usage of a household, compared to that of its neighbours, and commending good performance, to great results in consistent energy reduction (Energie123, 2014). 

10 Cascading through social structures

Existing social structures, both networks and segmentation, can be harnessed to induce spread of behaviour through large groups. The initial step; the adoption of the desired behaviour by key people, must be achieved with another strategy, but once this occurs, cascading techniques can quickly diffuse the new behaviour and contribute to its eventual normalisation in a group. 

Market segmentation is an effective strategy and allows control of communication, with time to react and correct the course of the campaign. Using social networks is more unpredictable, as communication happens autonomously between the nodes, and can backfire. Leveraging a network’s asymmetry of influence is especially important to guarantee the objective behaviour will spread and not be hindered by the network. If done correctly, it is a more powerful tool than mass media, since it allows interactive participation. 

Quinoa is an example of a food product which was marketed initially to a very specific consumer group with the aim of making consumption gradually spread through society. Quinoa’s protein density and essential amino acid content makes it a so called superfood and sparked its popularity in health-oriented consumers. After being adopted by this consumer group, the popularity of quinoa spread through society and even late-adopters have taken up the consumption of quinoa now (FAO, 2013).

Conclusions

From the public and civil society side, behavioral interventions have traditionally relied on providing information to consumers as main strategies to persuade consumers to break away from their habits. These interventions differ strongly from the approaches used by marketing and the private industry, which work with consumers’ desires and cognitive biases to encourage consumption. Consumers generally lack the interest and abilities to use information in their decision-making, and rather rely heavily on sensory cues and heuristics to make choices.

Consumer behavior can be altered by effective interventions, and is a necessary part of broader changes towards sustainability. Consumer decision-making is influenced by a complex set of social norms and individual wants and needs. It is subject to the chaotic workings of the human mind, with unexpected triggers, associations, and encoded behaviors. This makes the endeavor complicated yet not impossible.

Cognitive biases are the underlying feature that directs both the individual and the social behavioural processes. Effective interventions are those that harness these biases instead of working against them. In the long term, behavior can be established through habits, infrastructure, and social norms.

It must also be understood that both at the individual and social levels, behaviour is an unstable and dynamic phenomenon that will always change on its own by its very nature. Steering behavior to any desired state and maintaining it there is a permanent challenge that will require continuous and iterative interventions.

Colophon

Authors

Oscar Sabag Muñoz, Ilonka Marselis 

Research Team

Oscar Sabag Muñoz, Ilonka Marselis, Marie
Lakey, Madeline Donald

General Supervision

Eva Gladek

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