Do eco-labels on menus influence sustainable food choices?

Livestock production is estimated to contribute to 14.5% of human-induced global greenhouse gas (GHG) emissions. With global populations on the rise, demand for protein is set to soar – animal-derived protein alone is expected to double by 2050.

It’s been suggested that consumers, on the whole, are relatively unaware of how their diet could damage the environment. Eco-labelling – which can provide details of water and land usage, as well as GHG emissions – is one way to educate consumers about the environmental impacts of their diet.

But do they work? Research led by the University of Bristol, UK, has sought to find out whether applying eco-friendly ratings on menu items encourage diners to make choices which are kinder to the environment.

Beef, chicken, or veggie burrito?​

In an online survey, participants were asked to choose a hypothetical food item from a menu containing three choices: a beef burrito, a chicken burrito or a vegetarian burrito. Three mock-ups of food delivery app menus were created, each showing the three burrito options with different accompanying information.

All menus featured a photo of each item, as well as the calorie content, a Fairtrade logo, a spice indicator, and the price (which was the same for all options).

One mock-up also featured a ‘social nudge’, which the researchers describe as an indicator encouraging people to act according to the most sustainable option. In this case, the ‘social nudge’ resembled a gold star with the words ‘Most Popular’ placed next to the veggie option.

Another mock-up saw each burrito accompanied with a traffic light-style ranking of sustainability, with the vegetarian option being ‘green’ – indicating it was the most sustainable. The beef option scored ‘5’, indicating it was the least sustainable. The chicken option scored a ‘3’ and the vegetarian option scored a ‘1’.

Participants were randomly shown one of the three menu mock-ups and to select a burrito option.

The results: traffic light eco-labels work​

Findings revealed that 5% more of the 1,399 adult participants opted for the vegetarian option when the eco-labels were included, while 17% more went for vegetarian or chicken – the second most sustainable option.

Meanwhile, one-third of the participants who were given a ‘control’ menu without a social nudge or eco-label on it, selected the beef burrito. This dropped to 29% for those who had the social nudge menu, and even further down to 16% for those who had the eco-labelled menu.

“Adding a traffic light eco-label to menus increased the selection of more sustainable food items,” ​said lead author Katie De-loyde, research associate in Psychological Science. “Further, and somewhat surprisingly, participants were positive about the eco-label, with a huge 90% of participants supporting the idea.”​

Overall, the choice of a vegetarian burrito was relatively low (just 12% of participants opted for the veggie option), but the researchers judged this to be in line with previous studies indicating vegetarian food choice in meat-eating individuals to be 13%.

“Additionally, the choice of beef burrito was more likely to be reduced and replaced with a choice of chicken burrito, rather than choice of a vegetarian burrito increased,” ​noted the study authors. “However, this is consistent with research showing that people are more averse to choosing red-labelled products than they are enticed by green-labelled products.”​

Given that reducing beef intake is a specific component of British sustainability strategies, the researchers suggest eco-labelling could provide an effective method to achieve this.

“Pending replication in real-world settings, our results suggest future policy could include mandatory eco-labelling, just like the health traffic light system, on food products as a way to promote more sustainable diets,” ​noted De-loyde.

Source: Behavioural Public Policy​
‘Promoting sustainable diets using eco-labelling and social nudges: a randomised online experiment’
Published online 5 September 2022
DOI: https://doi.org/10.1017/bpp.2022.27
Authors: Katie De-loyde, Mark A. Pilling, Amelia Thornton, Grace Spencer, and Olivia M. Maynard.