When hearing the words “global climate crisis,” often the first things that come to mind are legislation and high-level or complex solutions. For many, food is a passing consideration, but what we choose to eat every day can have a huge impact. Globally, food systems are responsible for more than ⅓ of greenhouse gas emissions. This is largely due to meat production. To reach the Paris Agreement goal of 40% reduction in emissions, the research shows that we must reduce meat consumption. Experiments at the MIT Media Lab found that changing food labeling may be key in this endeavor.

In 2021, Alex Berke, a PHD student in the City Science group at the MIT Media Lab, made a pitch to the Lab community: align the Lab’s food expenditures with the Lab's sustainability goals by not serving meat at catered events. The proposal polarized the community—why? To answer this question the proposal transformed into a research project, which Berke presented back to the Media Lab community in 2023. Berke and Kent Larson, the director of the City Science group, co-authored a paper published in the journal Appetite entitled “The negative impact of vegetarian and vegan labels: Results from randomized controlled experiments with US consumers.” 

Within their paper, Berke and Larson highlight the extensive research across the globe that has described the disastrous impacts of our current food systems. They emphasize a simple shift that could impact the way meat and animal products are viewed:

“One might also consider the typical practice of labeling menu items as vegetarian or vegan, without corresponding (meat) labels for items containing meat, as a choice architecture that promotes items with meat as the default… Indeed, our studies find that vegetarian and vegan labels effectively deter consumers from choosing these options. Removing these labels may provide an extremely simple and low-cost means for restaurants and other institutions to reduce their environmental impact, with minimal changes to menus, and without impacting consumers' freedom of choice.”

This might cause one to wonder, how did Berke and Larson prove that these labels could make such a difference?

Berke conducted multiple randomized, controlled experiments to better understand the resistance to plant-based options and test a hypothesis that language, or labels, play an important role. The research question: Do vegan and vegetarian labels typically found on menus have a negative impact on people's likelihood to choose these more sustainable options?

The experiment results showed yes. These experiments initially studied the (unknowing) Media Lab community. The experiments were conducted through RSVP forms for events hosted at the Media Lab where catered food was served. For each event, the form asked attendees to choose between two menu options to eat at the event. And each time there were two versions of the form. One version had a "vegan" label on one of the meal options, and the other didn't. A random half of the attendees saw each form.  An example is below.

Analyzing RSVP forms for events where food would be served, Berke found that when people saw the “vegan” label, they were significantly less likely to choose that option. Furthermore, people often preferred the vegan option when it didn't have a label. The results from two such field studies are shown below. 

These experiments were then expanded to a broader US population. Again the results showed consumers were significantly less likely to choose an option when it had a "vegan" or "vegetarian" label. Furthermore, this study did not find that vegetarians and vegans were more likely to choose items with meat when the labels were removed, indicating that removing labels did not negatively impact them. 

The results suggest that vegetarian and vegan labels do more harm than good and that they should be removed from menus to help guide US consumers towards reduced consumption of animal products.

Conversations about food sustainability often focus on novel or expensive solutions, such as synthetic meats or hydroponics. But the research offers a much simpler and more low-cost option that could have an important impact. Removing vegetarian and vegan labels to normalize plant-based eating, and placing these options as a default, are immediately actionable changes towards more sustainable eating.

This experiment was approved by the Massachusetts Institute of Technology institutional review board (IRB): protocol 2203000615.