In the new study, published today in the International Journal of Behavioural Nutrition and Physical Activity, researchers tested the change in six English worksite cafeterias, asking managers to swap one meat-based lunch option for a vegetarian dish while keeping prices, choice and all other menu features the same. Customers were not told about the change, and meat options remained available.
Over seven weeks and more than 26,000 meals, the results showed the likelihood of choosing a vegetarian main increased by 41%.
Meals sold during the intervention were also healthier and more sustainable. On average, they contained around 26 fewer calories – about one cup of tea with milk and a teaspoon of sugar, as well as lower levels of saturated fat and salt, and had a lower environmental footprint, including an 8.5% reduction in greenhouse gas emissions per meal.
Crucially, the change did not affect business performance. There was no evidence of reduced revenue, fewer meals sold, or increased food waste.
The study is the first trial of this kind in workplace cafeterias, spanning both office and manual labour settings. It suggests that small changes to what's on offer can influence choices across a wide range of people.
Dr Elisa Becker , lead author and post-doctoral researcher in the Nuffield Department of Primary Care Health Sciences, said: 'The findings show that small changes to food environments can have a big effect without requiring customers to make extra effort, read labels or use self-control. 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.'
Feedback from staff and customers suggested the change was acceptable, easy to implement and largely went unnoticed, with concerns about dissatisfaction or waste not reflected in the data.
The researchers say the findings highlight a practical, scalable way to support healthier, lower-carbon diets, and could inform future workplace food policies across the UK.
The team are hoping to run similar simple menu change interventions in other industry settings and are always looking for new partners who would like to make a positive change towards health and sustainability.
