By: Stephanie Blaszczyk
In terms of energy consumption and global climate health, red meat is a Hummer and tomatoes are equivalent to a Toyota Prius.
With little knowledge of the food cycle, consumers vastly underestimate the impact their food choices can have on climate change, according to research recently published in Nature Climate Change. The same article also finds that access to climate information on food labels may soon allow them to adjust their shopping preferences to alleviate excess carbon emissions and greenhouse gases (GHG).
Previous research suggests that the food cycle – which includes everything from fertilizer production and methane released from animals to food storage and transportation – contributes 19 to 29 percent of global GHG emissions.
“This article came out of the insight that people don’t see energy in their food. It’s hidden,” said author Richard Larrick, a professor at Duke University, and a social psychologist interested in how people make decisions concerning energy information. “We wanted to determine if consumers would make environmentally friendly choices if provided with energy information on food labels.”
This study surveyed more than 1,000 American adults and asked them to estimate the energy consumed and the GHG released from the production of different foods and appliance use.
Participants consistently underestimated the energy consumed and the GHG emitted to produce food and operate appliances, but they underestimated, to a much greater degree, these values in relation to food production.
For example, participants estimated that the GHG released from operating a coffee maker were roughly equivalent to those from a serving of beef. In actuality, the participants underestimated the GHG released from the use of a coffee maker by a factor of 10 and the production of beef by a factor of 30.
These data confirmed Larrick’s suspicions: consumers are largely unaware of how much their daily choices affect the environment. The authors then hypothesized that consumers would alter their shopping choices if they were provided with food labels that offered clear, visual information about the carbon footprint of food choices.
To test this idea, they divided 120 participants into label and non-label groups. The researchers presented six different but equally priced cans of soups (three beef and three vegetable) to each participant and asked them to purchase three.
Each participant knew the name, price, and nutritional information of the six soups, but only the label group was given GHG emission information. Emission data included carbon dioxide emissions in “light-bulb minutes” — meaning how long a 100-watt incandescent light bulb would have to be on to make one serving of each soup — and an “eco” rating of the soup on a green to red color scale, where green indicated a lower carbon footprint and red indicated a higher carbon footprint.
As expected, the group with label information purchased fewer beef soups (about one can) in comparison to the non-label group (about one-and-a-half cans). These findings suggest that consumers may alter shopping patterns if provided with clear information regarding the climate implications of their choices — a possible path forward in the ongoing fight to slow climate change.
First author Adrian Camilleri, who began this research as a postdoctoral researcher with Larrick, acknowledged that creating food labels with carbon footprint data can be difficult and expensive. However, the environmental cost of inaction could be much more.
The authors do not have any immediate plans to push this particular work further or begin educational or industry outreach, but Camilleri did say, “We are currently discussing a project focused on a different solution to the problem, which is how to motivate people to reduce their waste.” When waste accumulates in landfills, it decomposes to produce methane, a GHG that is devastating to the global climate.
Empowering consumers to make informed decisions – such as the benefits of eating more fruits, vegetables, and protein from sources other than red meat – is a relatively simple way to help reduce GHG emissions.
With the United Nations proclamation that climate change currently affects every country in the world, the stakes for society have rarely been higher.
“Unfortunately, people don’t recognize that their food choices can mitigate the effects of climate change,” Larrick said.
This research shows that scientists and science communicators can promote behavioral changes by providing consumers with accurate and understandable information about the relationship between food and climate.
Adrian R. Camilleri was supported by a fellowship from the American Australian Association. Co-author D.P.-E. (not mentioned here) received financial support from the Center for Climate and Energy Decision Making (SES-0949710) funded by the National Science Foundation.