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Consumers underestimate the emissions associated with food but are aided by labels

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Food production is a major cause of energy use and GHG emissions, and therefore diet change is an important behavioural strategy for reducing associated environmental impacts. However, a severe obstacle to diet change may be consumers’ underestimation of the environmental impacts of different types of food. Here we show that energy consumption and GHG emission estimates are significantly underestimated for foods, suggesting a possible blind spot suitable for intervention. In a second study, we find that providing consumers with information regarding the GHG emissions associated with the life cycle of food, presented in terms of a familiar reference unit (light-bulb minutes), shifts their actual purchase choices away from higher-emission options. Thus, although consumers’ poor understanding of the food system is a barrier to reducing energy use and GHG emissions, it also represents a promising area for simple interventions such as a well-designed carbon label.
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Articles
https://doi.org/10.1038/s41558-018-0354-z
1UTS Business School, University of Technology Sydney, Ultimo, New South Wales, Australia. 2Fuqua School of Business, Duke University, Durham, NC,
USA. 3Duke University School of Law, Duke University, Durham, NC, USA. 4Nicholas School of the Environment, Duke University, Durham, NC, USA.
*e-mail: adrian.camilleri@uts.edu.au
There is a widespread scientific consensus regarding the
urgency to reduce GHG emissions1, and on the need to study
alternative interventions to do so. Much research has empha-
sized technological solutions such as greater energy efficiency and
increased use of renewable sources of energy2. More recently, it has
been recognized that diet change is also a potential solution worth
exploring35. Economic analysis has examined the virtues of mar-
ket-based mechanisms to influence demand, such as a carbon tax
that increases prices in line with social costs6. Increasingly, however,
social scientists have turned their attention to possible behavioural
interventions to influence demand7. For example, social psychologi-
cal research on social norms shows their effectiveness in producing
behaviour change in some contexts8,9. However, social norms are
problematic when the desired behaviour is rare10. Another interven-
tion approach is to ‘boost’ consumer decision-making by providing
relevant skills, knowledge and decision tools11. The efficacy of such
boosts requires first understanding the relevant knowledge gaps.
Attempts to modify behaviour typically presume that con-
sumers recognize the connection between their acts and the
consequences for energy consumption and GHG emissions12,13.
However, there is a growing body of research demonstrating
that consumers are often unaware or misinformed. For example,
Attari, et al.14 found that people had a rudimentary understanding
of the relative energy use of different electrical household appli-
ances (henceforth, appliances) and activities. On average, people
correctly recognized that refrigerators used more electricity than
light bulbs, but were insensitive to the true difference between
relatively high- and low-emitting appliances.
Research suggests that the food system contributes 19%–29%
of global GHG emissions15, which is similar to emissions from
US household electricity use16. Many factors combine to produce
such considerable emissions. Agriculture is highly industrialized.
Refrigeration and transportation tend to depend heavily on fos-
sil fuels. Natural gas is a key input in the manufacture of fertil-
izer. Cattle raised for beef and dairy products are major sources
of methane. Moreover, the process of raising meat is inherently
inefficient: fertilizer is used to grow feedstock, but only a small
portion of the feed becomes animal protein; the rest becomes
manure and methane. Thus, it takes 38 kg of plant-based protein
inputs to produce 1 kg of edible beef17. Finally, in many parts of
the world, burning forests to create grazing and agricultural land
also emits GHG emissions. A significant reduction in GHG emis-
sions from food could be achieved by changing consumers’ diet; in
particular, by moving toward more vegetarian or vegan meals18,19.
Even changing the type of meat consumed could have a large ben-
eficial environmental impact20.
Existing research, which typically asks consumers via survey
to indicate knowledge or agreement with facts about the environ-
mental impact of food, suggests that consumer awareness of the
environmental impact of meat production is low2124. Importantly,
however, those who believe that reducing meat consumption effec-
tively reduces GHG emissions are much more likely to intend to
reduce eating meat22,25.
Understanding consumersʼ perceptions of energy consump-
tion and GHG emissions of individual food items in a way similar
to Attari et al.14 is important because it can inform the design of
information interventions to help consumers understand the true
impact of their behaviours. Experimental studies investigating sim-
ple interventions to increase pro-environmental food consumption
behaviour have yielded only modest results26. Therefore, additional
research that identifies effective ‘boosts’ is needed.
One of the most straightforward ways to attempt to influence
food choice is through labels27. For example, a carbon label com-
municates information about the total amount of GHG emissions
from within a defined supply chain (for example, from cradle
to grave). Carbon labels provide information to consumers that
can be factored into purchase choices and also exert pressure on
manufacturers and retailers to provide consumers with lower-
emission options28.
The research associated with environmental labels on foods
is mixed. Some research suggests that consumers desire carbon
labels29,30. However, other research suggests that consumers barely
use environmental labels when making food choices31. Still other
research indicates that environmental labels can move consumption
Consumers underestimate the emissions
associated with food but are aided by labels
AdrianR.Camilleri 1*, RichardP.Larrick2, ShajutiHossain3 and DaliaPatino-Echeverri4
Food production is a major cause of energy use and GHG emissions, and therefore diet change is an important behavioural
strategy for reducing associated environmental impacts. However, a severe obstacle to diet change may be consumers’ under-
estimation of the environmental impacts of different types of food. Here we show that energy consumption and GHG emission
estimates are significantly underestimated for foods, suggesting a possible blind spot suitable for intervention. In a second
study, we find that providing consumers with information regarding the GHG emissions associated with the life cycle of food,
presented in terms of a familiar reference unit (light-bulb minutes), shifts their actual purchase choices away from higher-
emission options. Thus, although consumers’ poor understanding of the food system is a barrier to reducing energy use and
GHG emissions, it also represents a promising area for simple interventions such as a well-designed carbon label.
NATURE CLIMATE CHANGE | VOL 9 | JANUARY 2019 | 53–58 | www.nature.com/natureclimatechange 53
The Nature trademark is a registered trademark of Springer Nature Limited.
... On the one hand, adding information about the ecological impact of the dishes is feasible and both customers and restaurants have expressed an interest in such information [14,15]. Carbon labels that provide information about products' GHG emissions have the potential to reduce the carbon footprint of consumer choices [16,17]. Analogously, the field of health promotion has provided meta-analytic evidence that health-related labels move people toward healthier food choices [18]. ...
... According to a recent review of behaviorally informed interventions aimed at climate-friendly food consumption [10], carbon labels can be classified as disclosures when they provide ecological information about a food item (e.g., GHG emissions) and as warnings when the label features salient information connoted with emotional value (e.g., traffic-light colors). There are several studies in the context of health- [18,[23][24][25] and environment-related food choice [16,17,[23][24][25][26][27] in which the examined labels combined these two types of nudging. In other studies, default and non-default dishes were varied systematically on menus or board menus [28][29][30][31]. ...
... Labels that indicate food items' GHG emissions have been examined in dining [23,26,27,42,43] and grocery shopping [16,17,24,25,44] settings. In most cases, such labels combine explicit information (disclosure) with a color signal (warning; [10]). ...
Article
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In this study, we aimed to understand how restaurants can contribute to climate change mitigation via menu design. We investigated two types of interventions: changing the configuration of menu entries with variable side dishes so that the most climate-friendly option is set as the default and indicating the greenhouse gas emission of each dish via carbon labels . In an online simulation experiment, 265 participants were shown the menus of nine different restaurants and had to choose exactly one dish per menu. In six menus, the main dishes were presented with different default options: the side dish was associated either with the highest or with the lowest greenhouse gas emissions. The other three menus consisted of unitary dishes for which the default rules did not apply. All menus were presented either with or without carbon labels for each dish option. The results indicated that more climate-friendly dish choices resulting in lower greenhouse gas emissions were made with the low-emission than the high-emission default condition, and when carbon labels were present rather than absent. The effects of both interventions interacted, which indicates that the interventions partly overlap with regard to cognitive predecessors of choice behavior, such as attentional focus and social norms. The results suggest that the design of restaurant menus has a considerable effect on the carbon footprint of dining.
... Other changes attempt to address externalities, promoting the creation of public goods (for example, deceased organ availability 7 and charitable giving 8 ). In the domain of climate change mitigation, such interventions can strongly increase the number of consumers who sign up for a green energy contract 9,10 , reduce their residential energy use 11,12 , switch to a more cost-effective energy contract 13 or increase their willingness-to-buy environmentally friendly consumer goods 14 . In previous studies, behavioural 'nudges' either led to financial improvements for households (for example, resulting in a reduction of one's energy bill) or had no or only trivially negative impact on one's financial wellbeing. ...
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Behavioural public policy has received broad research attention, particularly in the domain of motivating pro-environmental behaviours. We investigate how far the efficacy of arguably one the most popular behavioural policy tools (green ‘default change’ nudges) depends on the associated cost. On the basis of a field study involving carbon offsets for over 30,000 flights booked by more than 11,000 airline customers, we show that green defaults have a large effect on voluntary climate action, even when several hundreds of Euros are at stake. The effect fully vanishes only as costs approach approximately €800. Berger et al. investigate green defaults under varying prices. Using field data from a flight compensation platform, they show that green defaults are effective. Their effectiveness, however, vanishes when costs become too high.
... Research has indicated that consumers have a poor understanding of the carbon footprint of different grocery products (Camilleri et al., 2019;Panzone et al., 2016;Sale, 2012). In the third experiment, we wanted to investigate whether repeated visits to a shop where graphical feedback was given about basket carbon footprint would result in more accurate representations of product carbon footprint through non-verbal (e.g., associative) ...
Thesis
I investigated the impact of economic and non-monetary instruments on sustainable grocery consumption. I tested whether these instruments reduce carbon footprint of shopping baskets and increase CO2 knowledge in an experimental online grocery shop. In the first empirical chapter, I disentangled the price effect and psychological impact of carbon tax by testing the effect of price adjustments, injunctive norms, and tax salience on basket CO2. In the second experiment, the impact of traffic lights carbon labels were also tested. Over two experiments, little or no impact of carbon tax on consumption was found. However, I found that carbon labels decreased basket CO2. While tax signposts did not improve knowledge, carbon labels and norms did. In the second empirical chapter, I decomposed the psychological and price effect of bonus-malus tax by testing the effect of price adjustments, tax salience, and tax justification messages on basket CO2. In the second experiment, I tested whether carbon labels had an impact on basket CO2 and knowledge. Over two experiments, no effect of bonus-malus on basket CO2 was found. However, carbon labels decreased basket CO2 and improved knowledge. I found evidence for the impact of tax signposts on knowledge. Additionally, in these first two empirical chapters, it was found that knowledge was a mediator of the relationship between labels and consumption. In the third empirical chapter, I investigated the impact of goal setting techniques and of the provision of carbon footprint information about the products and the basket on consumption and compared their effectiveness. Over three experiments, it was found that goal-setting techniques were effective in reducing basket CO2. Multiple visits ameliorated knowledge, in the goal setting condition, even though it did not decrease basket CO2. While colour coded labels, on their own, did not have an impact on basket CO2, numerical labels did, after combing the data of two experiments.
... There is ample research studying which arguments convince people to consume less meat apart from the impact of nudges or social norms. In incentive compatible experiments, carbon labels are found to reduce meat consumption (Camilleri et al. 2019;Perino et al. 2014). Comparing nutritional, climate protection and animal welfare appeals, the latter is more effective in reducing meat consumption than the other two (Palomo-Vélez et al. 2018). ...
... Data collection and analytic approach. The sample sizes for studies 1a, 1b and 2a were determined based on similar research on consumer misperceptions of the energy consumption related to food and household appliances 60 . The sample size for study 2b was determined to be at least twice the sample size of study 2a per experimental group to allow for a sufficiently powered replication and extension. ...
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All-electric vehicles remain far from reaching the market share required to meaningfully reduce transportation-related CO2 emissions. While financial and technological adoption barriers are increasingly being removed, psychological barriers remain insufficiently addressed. Here we show that car owners systematically underestimate the compatibility of available battery ranges with their annual mobility needs and that this underestimation is associated with increased demand for long battery ranges and reduced willingness to adopt electric vehicles. We tested a simple intervention to counteract this bias: providing tailored compatibility information reduced range concern and increased willingness to pay for electric vehicles with battery ranges between 60 and 240 miles, relative to a 50-mile-range baseline model. Compatibility information more strongly increased willingness to pay than did information about easy access to charging infrastructure, and it selectively increased willingness to pay for car owners who would derive greater financial benefits from adopting an electric vehicle. This scalable intervention may complement classical policy approaches to promote the electrification of mobility.
... Despite the available data on the factual environmental consequences of meat production, many people still seem unaware of the effects of their meat consumption on the environment (Macdiarmid et al., 2016;Camilleri et al., 2019;Bschaden et al., 2020). Recent reviews conclude that most consumers are not ready to make food choices based on environmental arguments (Austgulen et al., 2018;Sanchez-Sabate et al., 2019). ...
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Background Our daily food choices have a huge impact on the environment. Production of meat has a much larger impact compared with the production of vegetable-based proteins. In order to create a food production and supply system that is more sustainable and environmentally friendly, food consumption behaviour needs to change. A reduction of meat intake is necessary. The introduction of alternative protein sources (e.g., insects or cultured meat) might be one possibility to replace meat. Scope and approach The present systematic review identified 38 articles to answer the following three research questions: 1) Are consumers aware that meat consumption has a large environmental impact? 2) Are consumers willing to reduce meat consumption or substitute meat with an alternative? 3) Are consumers willing to accept meat substitutes and alternative proteins, such as insects or cultured meat? Key findings and conclusion Consumer awareness of the environmental impact of meat production is surprisingly low. This is true for consumers in various European countries. Likewise, willingness to change meat consumption behaviour in terms of reducing or substituting meat (e.g., by eating insects or meat substitutes) is low as well. How people can be motivated to decrease their meat consumption behaviour has been underexplored. In particular, experimental studies are lacking and further investigations should focus on strategies (e.g., nudging interventions) that might help to motivate pro-environmentally friendly meat consumption behaviour. Moreover, population-based studies are scarce, and we need more in-depth studies on the factors that increase people’s willingness to reduce or to substitute meat consumption.
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