One of the popular meat-based dishes served at the cafeteria. The meal still looked the same in the reduced version – the slices were just a little thinner. Credit: Gloria Sindermann.

A study by the University of Bonn has investigated how visitors can be motivated to accept smaller portions of meat.

Germans typically eat too much meat, which can have a negative impact on health and also be damaging for the environment and climate.

New research has found cafeteria owners are increasingly open to the idea of serving smaller portions of meat – especially for cost reasons – but how do you encourage their customers to choose smaller portions of meat?

Researchers at the University of Bonn have been investigating this question at a cafeteria in a rehabilitation clinic.

The desired effect was the biggest when the team at the cafeteria simply served smaller portions of meat and only topped them up when this was requested by customers. This approach was also largely accepted by patrons.

Meat consumption in industrial nations is much too high and this not only increases the risk of e.g. cardiovascular diseases.

Increasing levels of animal husbandry also aggravate the global food problem because the cultivation of animal feed uses valuable land that could be used to produce human food.

Animal husbandry also contributes to climate change: ruminants produce the greenhouse gas methane, while much more energy is consumed when producing food of animal origin than for plant-based alternatives.

Junior Professor Dr Dominic Lemken, from the Institute for Food and Resource Economics (ILR) at the University of Bonn, said: “Meat is more expensive than most of the side dishes [and] cafeterias want to reduce the meat portions on their plates for cost reasons alone.”

The question is what incentives are needed to encourage customers who are accustomed to consuming animal products to accept less meat and more sides or accompaniments on their plates.

Observation

A team headed by Lemken supported by Gloria Sindermann at the University of Göttingen carried out a study in a cafeteria at a rehabilitation clinic that serves around 200 portions of food every day to find out the answer.

The researchers logged data on a total of 5,966 meals chosen by customers from October 2022 until May 2023 – including information on whether the plates contained meat and what portions of meat were served.

The study was carried out anonymously and unnoticed by customers. The researchers also asked 125 customers whether they were satisfied with their meal.

The researchers had agreed a plan with the owners of the cafeteria before the study began.

No changes were made during an initial six-week observation phase and the staff at the cafeteria only amended the meat portions if this was specifically requested by customers.

The staff then changed their approach at the counter during a second more active phase by asking: How much meat do you want? An information board also informed customers that taking smaller portions of meat would help to feed more people around the world.

In a third phase, customers were automatically given less meat on their plates. Signs on the serving counter informed customers that they could also ask for a bigger portion if they wished. However, the staff only served a bigger portion if requested by the customer.

Desired change

The strategy used in the final phase is a type of ‘default nudging’, in which a nudge is used to trigger a desired change in behaviour in a targeted way. The shocking images on cigarette packs designed to discourage smokers are a good example of a nudge.

Doctoral candidate Ana Ines Estevez Magnasco from the team at the ILR said: “In contrast, the nudge in our study was that smaller portions of meat were served by default and customers had to make more effort to ask for a larger portion.”

Customers found it more comfortable to simply accept a smaller portion of meat.

How can cafeterias use these findings? Lemken recommends that cafeterias initially carry out surveys to find out whether smaller portions would be accepted as standard.

He said: “If customers reject this idea, the staff could actively ask customers how much meat they want when serving the food so as not to alienate anybody.”

However, there is still a need for more research in this area because there are sometimes significant differences between the range of food served by cafeterias and their regular clientele.

The results are published in the journal Environment and Behavior.