Carbon labels on restaurant menus can impact food choices

What unsustainable behavior needs to change:

What do you envision when you think of fast food or food delivery? Perhaps pizza, burgers, tacos, and döner kebab come to mind. While there are increasingly healthier options available, a significant portion of fast food choices still include meat.

A meat-based diet not only harms your health but also damages our planet. It leads to significantly higher CO2 emissions compared to more sustainable dietary choices. Moreover, fast food entails various negative externalities, including excessive fuel consumption for supply and processing, wasteful packaging, food waste, and water contamination. 

But let’s stick to CO2 emissions. A survey conducted by Carbon Trust among 10,000 individuals in 8 European nations revealed that 66% of respondents favoured carbon labelling on products. However, it is unclear whether they are merely professing their support or genuinely acting on their intentions.

The Green Nudge:

The UK-based Mexican restaurant chain, Wahaca, decided to highlight the climate impact by including a carbon label next to each menu item. 

They partnered with Swedish startup Klimato, which calculates and communicates the climate impact of food, to develop a labelling system that uses CO2 equivalents as a base. The calculations include the emissions for growing all the ingredients, as well as those generated when transporting, storing and cooking them.

Wahaca is now using carbon labels in three different dimensions:

• Low carbon (CO2e 0.6kg or lower): i.e. sweet potato burrito (0.46kg)
• Medium carbon (CO2e 0.6kg – 1.6kg): a grilled chicken club quesadilla,
• High carbon (CO2e 1.6kg or higher): such as a chargrilled steak burrito (3.04kg CO2e)

Although we lack concrete evidence in the Wahaca example, showing that highlighting the carbon impact affects food choice, multiple recent studies and trials have indicated that labelling can influence behaviour.

Psychology researchers from the University of Würzburg conducted a study which demonstrated that when individuals were presented with menus containing low-emission options, such as coconut curry with tofu instead of beef, the CO2e emissions decreased by almost one-third. Carbon labelling alone resulted in a 13.5% reduction in CO2e.

Researchers from Johns Hopkins University arrived at similar conclusions. In a randomised clinical trial involving 5,049 adults in the United States, 23% more participants in the high-climate impact label group opted for a sustainable option (i.e., non-red meat), and 10% more participants in the low-climate impact label group chose a sustainable option compared to the control group.