1. Background
Due to the critical role played by diet in health and disease, governments and world authorities globally invest in the development of dietary guidelines [
1‐
3], mandatory fortification of foods [
4], and setting and enforcing food safety standards in food production and retail environments [
5]. Additionally, public healthy eating campaigns continue to be funded worldwide, from large-scale national media campaigns, to small local community programs [
6]. In Australia, the current Health Star Rating system and the previous national social marketing campaign ‘Go for 2&5’ are examples of the substantial investment made by the Australian Government in supporting consumers to make choices for optimal health. However, the information from the scientific community is challenged by alternative and pseudo-health professionals as well as non-health trained health bloggers, celebrities and conspiracy theorists through the rise in Web 2.0 [
7]. These groups cast doubt on the legitimacy of government messages and activities, particularly through questioning areas of scientific uncertainty and progress, broadly contrasting ‘new ways’ (perceived scientific intrusion in food production; pesticides, genetic modification, food additives) as dangerous and ‘old ways’ (unpasteurised foods, organic processes) and ‘natural’ foods as safe. In combination with increased distance between food producers and consumers [
8], recent food safety incidents, and public awareness of unethical conduct in food production through incidents like the Horsemeat scandal [
9,
10], this strategy is effective in undermining consumer trust in food systems [
7,
11]. The Food system in this paper is taken to mean the methods by which food ingredients move from production; processing and distribution; and consumption [
12]. The various steps in the food system give rise to different forms of trust and distrust by consumers. For example, in Australia [
12], the UK [
13] and across Europe [
14] consumers report that pesticides, additives, artificial sweeteners, genetic modification and other forms of biotechnology in food continue to be high priority personal food safety concerns. Thus, for consumers what constitutes safe, healthy and ethically appropriate food, and whether to trust in conventional food systems to provide it, continues to be privately and publicly contested.
It is theorised that distrust in food systems may have consequences for consumer decision-making, particularly food choice and acceptance of expert advice [
15]. The avoidance of foods perceived to be unsafe or risky (for example, gluten or red meat) may lead to the exclusion of entire food groups from the diet, without medical advice to do so [
16]. If done without appropriate dietary substitutions, often requiring fortified products which are commonly themselves distrusted, this can compromise the nutritional adequacy of the diet. In Australia, organic food products are exempt from some mandatory fortification, therefore consumer avoidance of conventional food products and the exclusive use of organic products may also reduce exposure to the national fortification of bread flours with folate and thiamine, salt with iodine and tap water with fluoride. These public health fortification programs have all been shown to significantly reduce deficiencies and associated disease incidence at the population level [
17‐
19]. Indeed, distrust in the chlorination and fluoridation of tap water has been suggested to be linked with the movement towards drinking highly filtered or bottled water, contributing to rising childhood dental caries [
20]. These types of food behaviours are particularly concerning for nutritionally vulnerable groups such as children and pregnant women; commonly those who public health campaigns seek to protect. Additionally, Ekici [
21] found that distrusting consumers are more likely to shop outside of conventional food systems, relying instead on farmers markets and local produce. While this in and of itself is not problematic, and indeed may result in increased dietary variety and motivation to use fresh produce, there can be unintended consequences of the practices found within some alternative markets. For example, engagement with alternative markets and their associated community groups may increase access to products like unpasteurized milk, consumption of which is linked to outbreaks of food borne illness, and has resulted in deaths [
22,
23]. Additionally, previous research has also shown there to be a group of consumers, typically with fewer financial and social resources, who despite verbally expressing distrust in food do not have the resources to access farmers’ markets and other alternative food markets. They therefore control their family’s food intake in other, also potentially risky, ways such as ‘going without’ other staple food items to afford the higher price of organic produce in supermarkets [
24]. Yet while the theoretical case for trust impacting food choices and subsequently health outcomes is convincing, to date no research has empirically and comprehensively examined the link between consumers’ trust in food systems and their food choices, food safety practices, and health outcomes.
Partially this gap in knowledge is due to the complexity around measuring consumer trust in food. Instruments currently exist that include some components for measuring trust in food systems. The Edelman Trust barometer is an annual global report on various states and conditions of trust, typically in governments and business, but occasionally with a focus on food and beverages [
25]. Similar large scale surveys include the European Commission’s Eurobarometer [
14], the UK Food Standards Agency’s Food and You Survey [
26] and tracker [
13], the Food Standards Australia and New Zealand Consumer Attitudes surveys [
27,
28], the US Food and Health survey [
29], and the Australian survey of Social Attitudes [
30]. All these instruments however balance multiple data collection agendas and subsequently they do not comprehensively assess all dimensions of trust in food. They generally focus on a single dimension, like trust in regulatory bodies or industry, and so include only a few questions related to trust in food. Additionally, these surveys are typically not informed by sociological theories of trust.
A handful of academic studies have been conducted using instruments that aim to more comprehensively measure trust in food [
15,
31,
32], notably Poppe and Kjaernes [
31] exploration of trust in food in Europe. However, while this survey was sociologically underpinned it was not designed to be self-completed, reducing its efficiency when deployed in very large populations and its ability to be deployed quickly in response to changes in the food environment (e.g., a food incident). It also may have limited relevance to a global population due to the specification of food products incorporated within it. More recently, Benson et al. developed a toolkit to measure six aspects of trust across the food chain. These are: trust in organisations, product trust, interpersonal trust, trust in the food chain, organisation distrust, and general distrust [
33]. The scales from this tool can be used independently or as a whole. The Organisation for Economic Co-operation and Development (OECD) recently released guidelines for the measurement of trust generally, but this did not extend to a focus on trust in food [
34]. As such, while existing instruments provide a useful starting point, there is currently no comprehensive, sociologically informed, self-completed, quickly deployed instrument for the measurement of consumer trust in food and food systems.
Knowledge about the impact of trust in food systems on health would be powerful in two ways. First, public health campaigns with a food choice or safety focus typically aim to address lack of knowledge, positioning consumer education as central to success. However, if distrust in food systems is driving undesirable food choices and food safety practices, this ‘knowledge fix’ approach [
35‐
37] will need to be positioned alongside strategies for building food system trust to counter risky food behaviours. Second, an Australian study [
38] which presented issues on consumer food trust in relation to food governance actors and regulators found that due to the lack of research linking trust in food systems and concrete health outcomes, these actors consider distrust in the food system to be a ‘personal psychological issue’ and therefore not of public concern, or importantly, action. This position underrates the potential implications of trust in food systems, or lack thereof, for the success of existing substantial investments in public health. Therefore, if it is shown that there are risky health behaviours associated with distrust in food systems, programs to better address food trust become important, and what have up to now been considered ‘personal psychological issues’ become public health imperatives.
The aims of this paper are;
1)
to develop a comprehensive, sociologically informed, self-completed instrument to measure consumer trust in the food system, and
2)
to explore whether trust in the food system impacts
a)
adherence to national dietary guidelines,
b)
exposure to public health fortification programs, and
c)
adherence to recommended food safety practices.
4. Discussion
The DOTIFS scale developed in this research is the first comprehensive and sociologically informed assessment of consumer trust in food systems that can be self-administered online in large populations. Even with content validity questions included, the response duration averaged under 15 min, and the instrument was considered by respondents to be acceptably easy to use and comprehend. Most importantly, an overwhelming majority of participants felt the individual domain scores and overall trust score was a reasonably accurate reflection of their trust in food systems. Statistical analysis also showed scores significantly trended as predicted by participants stated level of trust, therefore we can be confident that population level trends in score reflect true differences in consumer trust in food systems, and the DOTIFS scale can be used as an accurate measure of changes in consumer trust over time.
Similarly, the Stage 2 study suggests there are differences in the way individuals with more or less trust in the food system comply with national dietary guidelines, are exposed to public health fortification programs, and adhere to recommended food safety practices. In brief, distrust of the food system was associated with a greater propensity to source food through markets or independent producers (supporting previous suggestions of this in the literature [
11,
21]), purchase food with reference to ethical, animal welfare and environmental concerns and to avoid use of chemicals in food production. Distrust of the food system was also associated with avoidance of foods without medical advice (again supporting theorisations in extant literature [
15,
16]); the consumption of products which have not been fortified and lapses in food safety such as consumption of unpasteurised dairy products and extended food purchasing time with frozen goods. Distrusters were also less likely to adhere to best by or use by dates. The benefit of the mixed-methods approach used here is that participants were able to articulate that it was frequently reasoning relating to trust considerations that caused them to make these alternative, and at times risky, choices. However, these qualitative data may also be used to form hypotheses and specific survey questions that could be used in conjunction with the DOTIFS scale to quantitively determine whether these trends persist in a population representative sample.
The trained critical ability of the highly educated sample of this study was advantageous at this early phase of instrument development as it enabled thorough critique of the DOTIFS scale and its content. However, while statistical analysis indicated no differences between formally educated groups in reported accuracy of scores, it means we have fewer perspectives from less formally educated groups around comprehension and ease of use. Nonetheless, the DOTIFS scale has been shown in this study to have considerable potential, and with further investment to conduct larger studies to determine repeatability and acceptability in a sample more representative of the general population, as well as to conduct factor analysis to comprehensively explore its dimensionality, it could have substantial impact in both the regulatory and policy settings.
4.1. Research, regulatory and policy futures for the DOTIFS scale
If baseline population data were collected the DOTIFS scale could then be used as a reactionary and quickly deployed assessment of consumer trust following a food safety incident or scandal, and the different domains would then assist in developing sociological theory regarding what areas of trust are impacted by such events, and therefore where to invest resources to best support trust in these situations. Similarly, the DOTIFS scale could be used to assess the impact of new policy and regulatory decisions relating to food, such as the introduction of the Health Star Rating food labelling system, or in consumer research examining different policy scenarios during decision making.
More widely, the DOTIFS scale has a number of features not found in similar scales. For example, Benson et al. [
33] conceptualise trust wholly differently to the sociological conceptualisation found here, citing trust as a personality trait, and defining trust and distrust as separate factors within their scale, which has an almost exclusive focus on the food chain and food safety. The DOTIFS scale however aims to capture the broad and interrelated aspects of the whole food system as seen and interpreted by consumers, and as is therefore consistent with a sociological conceptualisation of trust. The survey by Poppe and Kjaernes [
31] which explored trust in food in Europe was not self-completed and could not easily be deployed quickly to calibrate food trust at strategic times, e.g., during a food scare. The DOTIFS scale has both capabilities. However mindful that the window on public trust is often short-lived and limited, and the DOTIFS scale requires a considerable time investment from participants, further research could also explore the potential to extract a short-form version of the DOTIFS scale from that presented here. This could be incorporated regularly into the recurring large scale global assessments of general, not food specific, trust already being conducted [
13,
14,
25,
27,
30]. This would represent a considerable step forward in the monitoring of consumer trust globally, and potentially lead to international comparisons which, when explored using methodological approaches such as comparative health research [
54], could result in significant new insights into how consumer trust in food systems is built, broken and repaired.
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