Replacing just one meat-based dish with a vegetarian option in workplace canteens can significantly shift eating habits towards healthier and more sustainable choices, a new study has found.
In a trial led by researchers at the University of Oxford, managers at six workplace cafeterias, ranging from offices to assembly lines, agreed to swap out one meat or fish lunch option for a vegetarian alternative. They were given no instructions on which meals to introduce or how to price them.
Before the intervention, canteens typically offered at least three main meal options, with vegetarian choices accounting for between 7% and 27% of sales. However, after seven weeks and more than 26,000 meals served, vegetarian selections rose by 41%.
Elisa Becker, one of the study’s authors, said, “Instead of placing the burden on consumers, we found that simply offering more options that are better for health and the environment shifts eating behaviour in a healthier and more sustainable direction.”
Cafeterias adhered to the trial guidelines around 80% of the time. On days when they followed the rules precisely, the likelihood of a vegetarian dish being chosen increased by 63%, reinforcing that the results were driven by the intervention itself.
Popular vegetarian options included burgers, chilli and fajitas. These choices also improved nutritional outcomes, with average calories per meal dropping by 26.1 kcal—roughly equivalent to a cup of tea with milk and sugar. Levels of fat and salt also declined.
The environmental benefits were notable too. Greenhouse gas emissions per meal fell by 8.5%, comparable to the emissions saved from boiling around ten cups of tea. There were also reductions in water use and biodiversity impact based on ingredient analysis.
Despite initial concerns from cafeteria managers about potential revenue loss—and worries among some manual workers about reduced protein intake—these fears proved unfounded. There was no significant change in revenue or food waste, while protein levels dropped by just 2g per meal, a minor reduction compared to the recommended daily intake of 45–55g.
The study aimed to move beyond traditional “information-based” approaches, such as eco-labels, which rely on individuals to change behaviour. Instead, it highlights the effectiveness of reshaping food environments.
“If you focus on the food environment rather than the individual, you can be much more effective,” Becker said. She added that such changes are also more equitable, as they do not depend on consumers having additional knowledge, time or money.
The findings have been published in the International Journal of Behavioural Nutrition and Physical Activity.
