Meat production is taxing on the environment, and if we want to reduce our carbon footprint and tackle climate change, we need as many people to cut down on their meat consumption as possible. Restaurants and cafeterias can play a role in this — firstly, by offering plant-based alternatives.

Many restaurants and even fast food places already offer at least one vegetarian or vegan option, which is a good start, especially for those who regularly opt for such options. But could more plant-based options push more meat-eaters to go for a veggie option, at least once in a while?

With this question in mind, a team of researchers from the University of Westminster carried out an experiment in which menus where 75%, 50%, or 25% of items were vegetarian were allocated to 468 participants. The menus looked like this:

Researchers wanted to see whether having access to more vegetarian options makes a significant difference — apparently, it did, but only at 75% vegetarian options.

“We show that meat eaters were significantly more likely to choose a vegetarian meal when presented with a menu with 75% vegetarian items, but not when half (50%) were vegetarian,” the study notes.

There are significant shortcomings of the study — the fact that it has a small sample size, the fact that the sample size may not be representative for the entire population, the fact that the type of menu may also play a role — but researchers say that this study shows that interventions that offer more vegetarian options can push consumers can make towards more sustainable, low-meat and low-carbon options.

Dr. Beth Parkin, lead author of the study from The University of Westminster, said:

“This intervention shows the potential that the food service sector has in creating large-scale shifts to encourage meat eaters to change their preferences. The findings provide practical instruction on what percentage of their food offerings should be vegetarian if they are to succeed in encouraging sustainable eating behaviors. If the food service industry is to decrease its carbon footprint, they need to act by providing far more plant-based items than currently on offer.”

The meat and dairy industries account for nearly 60% of our agriculture emissions, or 15-20% of our total, planetary greenhouse gas emissions. It’s also one of the most impactful changes we, as individual consumers can do. Diet changes are paramount to avoiding catastrophic climate change, a growing body of scientific evidence is showing. This type of menu intervention can help reduce this negative impact, the researchers conclude.

The study has been published in the Journal of Environmental Psychology.