Nudging people to waste less food!

This week’s blog comes from Zuzana Machová. Zuzana comes from Slovakia originally but has been studying Economics and Social and Political Sciences in Trinity College, Dublin over the last year. Zuzana will be working with us over the next few weeks focussing on Goal 2: Zero Hunger as part of the #SDGchallenge.

Photo by U.S. Department of Agriculture.

Photo by U.S. Department of Agriculture.

Poverty and hunger are global problems. Whereas some people continue to fight to survive, almost one third of the food produced globally has been wasted. Moreover, according to the EU Commission (2010), 1kg of food waste accounts for approximately 1.9 kg of CO2 emissions. This is an important concern for our health and environment.

We have already heard so much about food waste and the “consumption society” we are living in. We have been told so many times to change our habits. But many would agree that to make a change, we need more people to get involved and be more responsible. Indeed, how we can affect how much food is wasted on the way from farms to our supermarkets and in restaurants?

Have you ever heard about a nudge? It is a simple trick to make people behave in a more socially beneficial way, without even being aware of doing so. Nudging aims to make easier for people to effortlessly take the “right decision”. In the last decade, the increasing popularity of this tool skyrocketed mostly in the field of marketing and behavioural economics. Notably, there is a lot of research going on that tackles individuals’ environmentally responsible and sustainable behaviour.

Can we nudge people to waste less food? I have recently come across an example of very efficient nudge that does not need any politician or extensive budget. Steffen Kalbekken and Håkon Saelen, two Norwegian researchers, tried to find out how they could nudge people to reduce their food waste in restaurants. They came up with a very simple idea that they tested during three months in 52 hotel restaurants.

Screen Shot 2016-06-14 at 12.11.56

Photo from

Their experiment included two nudges. They reduced the plate size and they put a new sign next to buffet tables saying: “Welcome back! Again! And again! Visit our buffet many times. That’s better than taking a lot once“. People are expected to judge the appropriate amount of food relative to the plate size. The plate size works as a so-called “reference point”. The new sign tackled the uncomfortable feeling coming from being seen by others to return to buffet several times. Thus, more people might prefer to return to buffet instead of taking too much food at once, more likely you are doing it as well. This is called the “herding” behaviour.  Personally, I remember the small amount of “guilt” I tend to feel when I come back to get a second crunchy croissant while having my breakfast in a B&B. What was the result of their experiment? Kalbekken and Saelen found that the both measures reduced food waste by roughly 20%. This seems quite efficient, doesn’t it?

If it is so efficient, why we do not encourage more restaurant managers to reduce plate size? The experiment which I described below was conducted in 2013. The great potential of nudging has been known for even longer. The reason might be that nudging is not as black ‘n’ white as it might seem.

First, would it work if people were aware of what was going on? This is still an unresolved discussion, even in a research world. Also, restaurant managers may be reluctant to apply these crazy ideas. The most frequent argument I came across was that consumers’ satisfaction can be affected by a plate size. Usually, the feeling of “luxury” is enhanced by greater plates. Even if, at first sight it seems a bit exaggerated, I can imagine that trying to cut bacon and save the rest of breakfast content from “escaping” the plate can be quite challenging, especially for small plates. However, if you want to lobby restaurant managers, you can still point that academic research has not managed to prove a sufficiently significant impact of plate size on the consumers’ satisfaction.

Ethics is equally an important issue for nudging. It can make us feel quite uncomfortable if science depicts us as a herd that is so easily manipulated. Also, the nudging can be questioned on a matter of freedom of choice.  Nevertheless, I would say that I do not see it that way. The majority of reports focused on nudging point that a clear and sensitive communication strategy is crucial. Moreover, the way the society functions is based on a complex bundle of human interactions. Therefore, I see the nudge as a specific approach how to “steer” these interactions towards a more sustainable outcome without harming one’s well-being. 

Yet, nudging is an extremely hard thing to do and it demands a lot of creativity and dedication. Certainly, there are people who can work on that further but what about the rest of us? Apart from recommending nudging in a hotel guest book, there is still a bunch of other “precautions” that we can take to reduce our food waste.

If you know the restaurant where are you going to eat, think of how big the portions were  they served you the last time and whether or not it was too much. In several restaurants I have tried ordering only one dish and asked whether we could get one extra plate to split it between two persons. So far, restaurant staff have always been very kind to do so! Also, the grams indicated beside dishes in a menu are also very useful to assess the amount of food you are getting. It might not be straightforward, right at the beginning, but after some time you will get to know approximately what “weight” is sufficient to silence your groaning stomach.

In a word, nudging has a big potential for all of us and there are still solutions for problems we try to tackle. It is also important to spread the message and do not fall into despair because so many things can be done and they are not evident at the first sight.

Do you feel motivated to make a change? So talk and share to increase the food waste awareness and get involved in our #SDGChallenge. More people participate, bigger change we can make together!

Literature and information sources for the article:

Matthias Lehner, Oksana Mont, Eva Heiskanen, Nudging – A promising tool for sustainable consumption behaviour?, Journal of Cleaner Production, Available online 12 December 2015

Steffen Kallbekken, Håkon Sælen, ‘Nudging’ hotel guests to reduce food waste as a win–win environmental measure, Economics Letters, Volume 119, Issue 3, June 2013

For those who want to know more about nudging:

Cass Sunstein Nudge: Improving decisions about health, wealth, and happiness (2008)

Leave a comment

Your email address will not be published. Required fields are marked *